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1

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

PubMed Central

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 然 iron, 0.707 然 manganese, 0.624 然 molybdenum and 3.38 然 nickel. The maximum hydrocarbon content could be achieved when the culture media contained 10.43 然 iron, 6.53 然 manganese, 0.012 然 molybdenum and 1.73 然 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.

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

2012-01-01

2

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

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

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

2001-01-01

3

Hydrocracking of the oils of Botryococcus braunii to transport fuels  

SciTech Connect

Hydrocarbon oils of the alga Botryococcus braunii, extracted from a natural 'bloom' of the plant, have been hydrocracked to produce a distillate comprising 67% a petrol fraction, 15% an aviation turbine fuel fraction, 15% a diesel fuel fraction and 3% residual oil. The distillate was examined by a number of standard petroleum industry test methods. This preliminary investigation indicates that the oils of B. braunii are suitable as a feedstock material for hydrocracking to transport fuels.

Hillen, L.W.; Pollard, G.; Wake, L.V.; White, N.

1980-07-01

4

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

Microsoft Academic Search

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

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

1993-01-01

5

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

Microsoft Academic Search

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 orangeyellow and their shape dominantly changed to grape-like with long branches. Photosynthetic carbon fixation activity was higher

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

6

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

SciTech Connect

A Coorongite sample of Lake Balkash (Kazakhstan, CIS) was analyzed in detail by [sup 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 of n-alkanes and n-alk-1-enes 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-[omega][sup 9]-ones, and alk-1-en-[omega][sup 10]-ones with C[sub 27], C[sub 29], and C[sub 31] carbon atoms clearly indicated that C[sub 27], C[sub 29], and C[sub 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. 43 refs., 14 figs., 1 tab.

Gatellier, J.P.L.A.; De Leeuw, J.W.; Sinninghe Damste, J.S. (Delft Univ. of Technology (Netherlands)); Derenne, S.; Largeau, C.; Metzger, P. (UA CNRS 1381, Paris (France))

1993-05-01

7

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

NASA Astrophysics Data System (ADS)

A Coorongite sample of Lake Balkash (Kazakhstan, CIS) was analyzed in detail by 13C-NMR, FTIR, Curie point pyrolysisgas chromatographymass 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.

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

1993-05-01

8

Seawater-cultured Botryococcus braunii for efficient hydrocarbon extraction.  

PubMed

As a potential source of biofuel, the green colonial microalga Botryococcus braunii produces large amounts of hydrocarbons that are accumulated in the extracellular matrix. Generally, pretreatment such as drying or heating of wet algae is needed for sufficient recoveries of hydrocarbons from B. braunii using organic solvents. In this study, the Showa strain of B. braunii was cultured in media derived from the modified Chu13 medium by supplying artificial seawater, natural seawater, or NaCl. After a certain period of culture in the media with an osmotic pressure corresponding to 1/4-seawater, hydrocarbon recovery rates exceeding 90% were obtained by simply mixing intact wet algae with n-hexane without any pretreatments and the results using the present culture conditions indicate the potential for hydrocarbon milking. Highlights: Seawater was used for efficient hydrocarbon extraction from Botryococcus braunii. The alga was cultured in media prepared with seawater or NaCl. Hydrocarbon recovery rate exceeding 90% was obtained without any pretreatment. PMID:23799107

Furuhashi, Kenichi; Saga, Kiyotaka; Okada, Shigeru; Imou, Kenji

2013-06-14

9

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

Microsoft Academic Search

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

Reno T. Nguyen; H. Rodger Harvey

2003-01-01

10

Hydrocarbon fuels from solar energy via the alga Botryococcus brauni  

Microsoft Academic Search

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

L. W. Hillen; D. R. Warren

1976-01-01

11

Isolation of herbicide-resistant mutants of Botryococcus braunii.  

PubMed

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

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

2011-08-03

12

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

PubMed

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

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

2013-04-17

13

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

Microsoft Academic Search

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

Halil Berberoglu; Pedro S. Gomez; Laurent Pilon

2009-01-01

14

Interactions of Botryococcus braunii Cultures with Bacterial Biofilms  

Microsoft Academic Search

Unicellular microalgae generally grow in the presence of bacteria, particularly when they are farmed massively. This study\\u000a 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\\u000a (?107108 culturable cells per gram microalgae). Furthermore, we identified the culturable bacteria forming

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

2010-01-01

15

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)*  

PubMed Central

Background 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. Results A de novo assembly of 1,334,609 next-generation pyrosequencing reads form the Showa strain of the B race of B. braunii yielded a transcriptomic database of 46,422 contigs with an average length of 756 bp. Contigs were annotated with pathway, ontology, and protein domain identifiers. Manual curation allowed the reconstruction of pathways that produce terpenoid liquid hydrocarbons from primary metabolites, and pathways that divert photosynthetic carbon into tetraterpenoid carotenoids, diterpenoids, and the prenyl chains of meroterpenoid quinones and chlorophyll. Inventories of machine-assembled contigs are also presented for reconstructed pathways for the biosynthesis of competing storage compounds including triacylglycerol and starch. Regeneration of S-adenosylmethionine, and the extracellular localization of the hydrocarbon oils by active transport and possibly autophagy are also investigated. Conclusions The construction of an annotated transcriptomic database, publicly available in a web-based data depository and annotation tool, provides a foundation for metabolic pathway and network reconstruction, and facilitates further omics studies in the absence of a genome sequence for the Showa strain of B. braunii, race B. Further, the transcriptome database empowers future biosynthetic engineering approaches for strain improvement and the transfer of desirable traits to heterologous hosts.

2012-01-01

16

Studies on the nutritional requirements of the oil-producing algar Botryococcus braunii  

SciTech Connect

Studies were carried out on the ability of the algae Botryococcus braunii to grow in the presence of possible carbon sources. Sources examined included compounds for C1-C6, as well as the disaccharides sucrose and lactose. Dividing times were decreased from an average of over 1 week to less than 3 days by addition of the appropriate carbon sources. Examination of the oils produced in the presence and absence of exogenous carbon indicated no differences. However, the total biomass produced in the presence of a usable carbon source exceeded that produced in the carbon's absence. 10 references.

Weetall, H.H.

1985-10-01

17

Lipids from the Microalga, 'Botryococcus braunii'.  

National Technical Information Service (NTIS)

A high lipid, high hydrocarbon green algae was grown in various chemical and physical environments to optimize the production of biomass and of lipids. Among the variables were temperature, light intensity, light cycling, buffering, and major and minor nu...

S. Aaronson

1981-01-01

18

Identification of unique mechanisms for triterpene biosynthesis in Botryococcus braunii  

PubMed Central

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 500MYA. 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.

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

2011-01-01

19

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

Microsoft Academic Search

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

Ela Eroglu; Anastasios Melis

2010-01-01

20

Growth characteristics of Botryococcus braunii 765 under high CO 2 concentration in photobioreactor  

Microsoft Academic Search

To understand the potential of cultivating Botryococcus braunii with flue gas (normally containing high CO2) for biofuel production, growth characteristics of B. braunii 765 with 220% CO2 aeration were investigated. The results showed that the strain could grow well without any obvious inhibition under all tested CO2 concentrations with an aeration rate of 0.2vvm, even without any culture pH adjustment

Yaming Ge; Junzhi Liu; Guangming Tian

2011-01-01

21

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

Microsoft Academic Search

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

F. Behar; S. Derenne; C. Largeau

1995-01-01

22

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

PubMed

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

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

2012-01-10

23

Mechanisms of flash pyrolysis of ether lipids isolated from the green microalga Botryococcus braunii race  

Microsoft Academic Search

Two types of ether lipids isolated from the microalga Botryococcus braunii have been subjected to flash pyrolysis. The pyrolysis products were separated and analyzed by GC\\/MS. The nature and distribution of the pyrolysis compounds gave clues to the different mechanisms involved in the pyrolysis of ether-linked alkyl chains. The relatively abundant presence of alkenes, alkadienes, alken-9-ones and alken-10-ones with chain

J. S. Sinninghe Damst; F. Gelin; J. P. L. A. Gatellier; P. Metzger; S. Derenne; C. Largeau; J. W. de Leeuw

1993-01-01

24

Two-phase extraction culture of Botryococcus braunii producing long-chain unsaturated hydrocarbons  

Microsoft Academic Search

Hydrocarbon recovery was 32% and the total production of hydrocarbon in a two-phase extraction culture of Botryococcus braunii was 675mgl-1, which was 19% higher than that of single-phase culture. Addition of 60ml dihexyl ether at mid-growth phase gave the highest yield. Specific growth rate and recovery of hydrocarbon in this case were 0.022h-1 and 26%, respectively.

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

2001-01-01

25

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

PubMed

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

Eroglu, Ela; Melis, Anastasios

2009-12-14

26

Raman Spectroscopy Analysis of Botryococcene Hydrocarbons from the Green Microalga Botryococcus braunii*  

PubMed Central

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 (C30) is metabolized by methylation to give intermediates of C31, C32, C33, and C34, with C34 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 16001700 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.

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

2010-01-01

27

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

PubMed

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

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

2010-08-12

28

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

PubMed

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 893.79mg/L, respectively, was attained at 100mL/min of solvent recycling rate through three times of processes for 66days. 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

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

2013-05-25

29

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

SciTech Connect

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 from the latter, termed PRB L, is based on C{sub 40} isoprenoid chains with a lycopane-type skeleton. Recent comparative studies of PRB L and of Botryococcus-derived sediments provided the first example of kerogen formation via the selective preservation of an {open_quotes}isoprenoid{close_quotes} algaenan. The present study is concerned with PRB L pyrolyses in sealed gold tubes under various temperature/time conditions (260-350{degrees}C, 0.5-69 h). For the conversion rates thus obtained, ranging from 30 to 100%, a complete mass balance of the different families of pyrolysis products was established; most of the C{sub 1} to C{sub 40} pyrolysate constituents were identified and the abundances of the above compounds and their variations with conversion progress were determined. This study thus allowed us (1) to derive further information about PRB L chemical structure (location of the ether bridges, contribution to linear chains and their relationships with the C{sub 40} isoprenoid ones), (2) to determine the behaviour of this isoprenoid algaenan to thermal stress (timing of the formation of the secondary products, and further degradations), and (3) to show, in connection with previous studies, that PRB L-derived kerogens should exhibit pronounced differences relative to standard type I kerogens, the latter being based on polymethylenic chains, regarding not only the structure of the generated products but also the timing of oil generation (upward shift of the catagenesis zone).

Behar, F. [Institut Francais du Petrole, Rueil-Malmaison (France); Derenne, S.; Largeau, C. [Laboratoire de Chimie Bioorganique et Organique Physique, Paris (France)

1995-07-01

30

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

PubMed

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

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

2012-06-09

31

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

Microsoft Academic Search

This paper reports ReaxFF MD simulation results on pyrolysis of a molecular model of the algaenan Botryococcus braunii race L biopolymer, specifically, ReaxFF predictions on the pyrolysis of prototypical chemical structures involving aliphatic chain esters and aldehydes. These preliminary computational experiments are then used to analyze the thermal cracking process within algaenan race L biopolymers. The simulations indicate that the

Elodie Salmon; Adri C. T. van Duin; Fran蔞is Lorant; Paul-Marie Marquaire; William A. Goddard III

2009-01-01

32

Simple, Rapid and Cost-Effective Method for High Quality Nucleic Acids Extraction from Different Strains of Botryococcus braunii  

PubMed Central

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.

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

33

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

PubMed

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

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

2012-05-25

34

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

PubMed

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 28days respectively, which vary upon culture durations. The energy value (54.69kJ/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

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

2013-09-20

35

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

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

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

1994-01-01

36

Scope and limitations of flash pyrolysis-gas chromatography-mass spectrometry as revealed by the thermal behaviour of high-molecular-weight lipids derived from the green microalga Botryococcus braunii  

Microsoft Academic Search

Curie point pyrolysis?gas chromatography\\/mass spectrometry studies of four types of high-molecular-weight (HMW) lipids isolated from the green microalga Botryococcus braunii race A were performed to determine the thermal behaviour of these lipids and to propose mechanisms of pyrolysis for these types of compounds. Although two types of lipids induced detectable pyrolysis products upon heating of the ferromagnetic wires at Curie

J. S. Sinninghe Damst; F. Gelin; J. W. de Leeuw; Sylvie Derenne; Claude Largeau; Pierre Metzger

1994-01-01

37

Occurrence of Only One Form of Glutamine Synthetase in the Green Alga Monoraphidium braunii.  

PubMed Central

Anion-exchange chromatography of crude extracts from the green alga Monoraphidium braunii yielded two glutamine synthetase (GS) activities. The ratio of activities was markedly different when crude extracts were subjected to various processing conditions but was not influenced by environmental factors of cell cultures. However, high performance liquid chromatography anion-exchange chromatograms showed only one GS if the crude extracts were processed immediately after cell disruption. Moreover, standard chromatography of crude extracts obtained in the absence of dithioerythritol, a reductant generally used in disruption buffers, yielded a single activity peak. Enzyme samples from the two activities obtained in the presence of dithioerythritol were purified for physicochemical characterization and antibody production. Both enzyme samples exhibited similar reactions to different inactivating agents and were undistinguishable by size-exclusion chromatography and native polyacrylamide gel electrophoresis. Additionally, the two GS preparations showed absolute antigenic identity as demonstrated by immunodiffusion and immunoblotting experiments. Immunocytochemistry of M. braunii cryosections evidenced a chloroplast-specific distribution of the enzyme, which rules out the existence of a cytoplasmic counterpart. All these results support the proposal that M. braunii possesses only one form of GS.

Garcia-Fernandez, J. M.; Lopez-Ruiz, A.; Toribio, F.; Roldan, J. M.; Diez, J.

1994-01-01

38

Occurrence of Only One Form of Glutamine Synthetase in the Green Alga Monoraphidium braunii.  

PubMed

Anion-exchange chromatography of crude extracts from the green alga Monoraphidium braunii yielded two glutamine synthetase (GS) activities. The ratio of activities was markedly different when crude extracts were subjected to various processing conditions but was not influenced by environmental factors of cell cultures. However, high performance liquid chromatography anion-exchange chromatograms showed only one GS if the crude extracts were processed immediately after cell disruption. Moreover, standard chromatography of crude extracts obtained in the absence of dithioerythritol, a reductant generally used in disruption buffers, yielded a single activity peak. Enzyme samples from the two activities obtained in the presence of dithioerythritol were purified for physicochemical characterization and antibody production. Both enzyme samples exhibited similar reactions to different inactivating agents and were undistinguishable by size-exclusion chromatography and native polyacrylamide gel electrophoresis. Additionally, the two GS preparations showed absolute antigenic identity as demonstrated by immunodiffusion and immunoblotting experiments. Immunocytochemistry of M. braunii cryosections evidenced a chloroplast-specific distribution of the enzyme, which rules out the existence of a cytoplasmic counterpart. All these results support the proposal that M. braunii possesses only one form of GS. PMID:12232093

Garcia-Fernandez, J. M.; Lopez-Ruiz, A.; Toribio, F.; Roldan, J. M.; Diez, J.

1994-02-01

39

Cytochrome c6 from the green alga Monoraphidium braunii. Crystallization and preminary diffraction studies.  

PubMed

Cytochrome c(6), a plastocyanin functionally interchangeable electron carrier between the chlorophyll molecule P700 of photosystem I and cytochrome f from cytochrome b(6)f complex, has been isolated from the green alga Monoraphidium braunii and crystallized by the vapour-diffusion technique in sodium citrate. Crystals belong to space group R3, with cell dimensions a = b = 51.93 (5) and c = 80.5 (1) A (hexagonal axes), with one molecule per asymmetric unit. They diffract beyond 1.9 A under a Cu Kalpha rotating-anode source, with an anomalous signal that allows the positioning of the heme Fe atom in the unit cell. PMID:15299324

Fraz緌, C; Dias, J M; Matias, P M; Rom緌, M J; Carrondo, M A; Herv嫳, M; Navarro, J A; de la Rosa, M; Sheldrick, G M

1995-03-01

40

Biotransformation of sinapic acid by the green algae Stichococcus bacillaris 155LTAP and Ankistrodesmus braunii C202.7a  

Microsoft Academic Search

Sinapic acid was bioconverted by the green alga Stichococcus bacillaris into 4-hydroxy-3,5-dimethoxybenzoic acid, 4-hydroxy-3,5-dimethoxybenzaldehyde and 4-hydroxy-3,5-dimethoxybenzylic alcohol. Incubation of sinapic acid in a culture of the alga Ankistrodesmus braunii gave 3,6-dihydroxy-2,4-dimethoxy-7H-benzocyclohepten-7-one, a new compound formed by bioconversion of thomasidioic acid, the primary oxidative product of sinapic acid.

Marina DellaGreca; Gabriele Pinto; Antonino Pollio; Lucio Previtera; Fabio Temussi

2003-01-01

41

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

Microsoft Academic Search

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

Sara S. Kuwahara; Joel L. Cuello

42

Removal of bisphenol A by the freshwater green alga Monoraphidium braunii and the role of natural organic matter.  

PubMed

Phytoremediation of waters by aquatic organisms such as algae has been recently explored for the removal of organic pollutants possessing endocrine disrupting capacity. Monoraphidium braunii, a green alga known for rapid growth and good tolerance to different natural organic matter (NOM) qualities, was tested in this study for the ability to tolerate and remove the endocrine disruptor bisphenol A at concentrations of 2, 4 and 10mgL(-1), either in NOM-free or NOM-containing media. NOM at concentrations of 2, 5 and 20mgL(-1) of DOC, was added because it may interfere with xenobiotics and modify their effects, modulate algal growth performances or produce a trade-off of both effects. After 2 and 4 days of algal growth, the cell number and size, the maximum quantum yield of photosystem II in the dark or light adapted state, and the chlorophyll a content were recorded in order to evaluate the algal response to bisphenol A. Moreover, the residual bisphenol A was measured in the algal cultures by chromatographic technique. Results indicated that after 2 and 4 days bisphenol A at the lower concentrations was not toxic for alga, whereas at the highest concentration it reduced algal growth and photosynthetic efficiency. The sole NOM and its combinations with bisphenol A at the lower concentrations increased the cell number and the chlorophyll a content of algae. After 4-day growth, good removal efficiency was exerted by M. braunii at concentrations of 2, 4 and 10mgL(-1) removing, respectively, 39%, 48% and 35% of the initial bisphenol A. Lower removal percentages were found after 2-day growth in the different treatments. NOM at any concentration scarcely influenced the bisphenol A removal. On the basis of data obtained, the use of M. braunii could be reasonably recommended for the phytoremediation of aquatic environments from bisphenol A. PMID:22209372

Gattullo, C Eliana; B鄣rs, Hanno; Steinberg, Christian E W; Loffredo, Elisabetta

2011-12-29

43

Non-siliceous algae in a five meter core from Lake Kinneret (Israel)  

Microsoft Academic Search

The composition and succession of non-siliceous algae, studied in a five meter core from Lake Kinneret (Israel), are described. Only Chlorophyta species were recorded, probably due to the standard palynological sample processing which was used. In the lower part of the core, from the bottom to 300 cm (interval 55002500 years B.P.), Botryococcus braunii was the only common alga. Relevant

U. Pollingher

1986-01-01

44

Effect of glutamine on glutamine-synthetase regulation in the green alga Monoraphidium braunii  

Microsoft Academic Search

Glutamine-synthetase (GS; EC 6.3.1.2) activity and protein levels were measured in crude extracts from Monoraphidium braunii N輑geli, strain 202-7d, cultures grown under different nitrogen sources. Only ammonium and l-glutamine promoted a partial enzyme inactivation, which, in the case of l-glutamine, was accompanied by a significant repression of GS. Methionine sulfoximine (MSX), a strong inhibitor of GS, produced a drastic inactivation

Jos Manuel Garcia-Fern嫕dez; Antonio L鏕ez-Ruiz; Jos Alhama; Jos Manuel Rold嫕; Jess Diez Dapena

1995-01-01

45

Solution structure of oxidized cytochrome c6 from the green alga Monoraphidium braunii.  

PubMed

Cytochrome c6 from Monoraphidium braunii, an 89-amino acid electron transfer protein, has been investigated by NMR in solution, in its oxidized form, at pH 7 and 300 K. By using a combination of COSY, TOCSY, and NOESY experiments, 84% of the proton resonances have been assigned. A total of 1668 experimental NOE constraints, 1109 of which were meaningful, together with 288 pseudocontact shifts, have been used to determine the structure in solution. This is represented as a family of 40 structures which have been energy minimized. The rmsd values with respect to the mean structure are 0.57 +/- 0.08 and 0.94 +/- 0.09 A for the backbone and heavy atoms, respectively. The structure has been found to be very similar to that of the reduced form, except for a rearrangement in propionate 7, a feature which has been observed in all c-type cytochromes investigated so far. Such a feature could be relevant for the efficiency of the electron transfer pathway with either the oxidizing or the reducing partners. Other differences in the oxidation states have been noted in the region proposed to be involved in the interaction with the physiological partners. PMID:9538000

Banci, L; Bertini, I; De la Rosa, M A; Koulougliotis, D; Navarro, J A; Walter, O

1998-04-01

46

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

PubMed Central

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 Qui隳nes, PJ Aparicio [1990] Inorganic Nitrogen in Plants and Microorganisms, Springer-Verlag, Berlin, pp 171-177; MA Qui隳nes, 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.

Aparicio, Pedro J.; Quinones, Miguel A.

1991-01-01

47

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

PubMed

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 Qui隳nes, PJ Aparicio [1990] Inorganic Nitrogen in Plants and Microorganisms, Springer-Verlag, Berlin, pp 171-177; MA Qui隳nes, 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 CO(2)-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 CO(2) to cells. However, cells under high CO(2) 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 CO(2)-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

Aparicio, P J; Qui隳nes, M A

1991-02-01

48

A thermodynamic study by laser-flash photolysis of plastocyanin and cytochrome c6 oxidation by photosystem I from the green alga Monoraphidium braunii.  

PubMed

Plastocyanin and cytochrome c6 from the green alga Monoraphidium braunii reduce the photo-oxidized algal photosystem I (PSI) reaction center chlorophyll (P700) with similar kinetics, as expected from their functional equivalence. The observed P700+ reduction rate constants show a non-linear dependence on metalloprotein concentration, which indicates a (minimal) two-step kinetic mechanism involving complex formation prior to electron transfer. The dependence of the observed rate constants on NaCl concentration suggests that the electrostatic interaction forces between the negatively charged donor proteins and PSI are repulsive at neutral pH and relatively low ionic strength (I), although attractive dipole-dipole interactions may play a role at higher ionic strengths. Activation parameters for P700+ reduction by cytochrome c6 and plastocyanin have been determined by studying the temperature dependence of the respective rate constants at varying ionic strength and pH. Changes in NaCl concentration and pH induce significant changes in the activation free energy of the overall reaction, even though the corresponding values for activation enthalpy and entropy undergo changes in opposite directions. Such a compensation effect between enthalpy and entropy is observed with both cytochrome c6 and plastocyanin. Protein concentration dependencies of the observed rate constants at different temperatures has allowed an estimate of the free energy change during complex association, as well as the activation parameters for electron transfer, according to a two-step kinetic model. PMID:8026478

D燰z, A; Herv嫳, M; Navarro, J A; De La Rosa, M A; Tollin, G

1994-06-15

49

Nitrate Reductase from Monoraphidium braunii  

PubMed Central

Homogeneous nitrate reductase (EC 1.6.6.2) from Monoraphidium braunii was obtained by means of affinity chromatography in blue-Sepharose and gel filtration. After electrophoresis in polyacrylamide, gel slices containing pure nitrate reductase were disrupted and injected into previously unimmunized rabbits. The antiserum produced after several weeks was found to inhibit the different activities of nitrate reductase to a similar degree. Monospecificity of the antiserum was demonstrated by Ouchterlony double diffusion and crossed immunoelectrophoresis. The antibodies were purified by immunoabsorption to Sepharose-bound nitrate reductase. The intracellular location of nitrate reductase in green algae was examined by applying an immunocytochemical method to M. braunii cells. Ultrathin frozen sections were first treated with immunopurified anti-nitrate reductase monospecific antibodies, followed by incubation with colloidal gold-labeled goat antirabbit immunoglobulin G as a marker. The enzyme was specifically located in the pyrenoid region of the chloroplast. Images Fig. 1 Fig. 2 Fig. 4 Fig. 5

Lopez-Ruiz, Antonio; Roldan, Jose Manuel; Verbelen, Jean Pierre; Diez, Jesus

1985-01-01

50

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

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

S. Derenne; C. Largeau; F. Behar

1994-01-01

51

Reflectance FT-IR microspectroscopy of fossil algae contained in organic-rich shales  

SciTech Connect

A microscope sampling accessory interfaced to a Fourier transform infrared (FT-IR) spectrometer has been employed to characterize the remains of individual microscopic fossil algae and algal colonies contained in organic-rich shales. The microspectrometer is able to measure reflectance IR spectra of samples with cross-sectional areas as small as 20 [times] 20 microns. The fossil algae studied include the colonial green alga Botryococcus braunii, the unicellular green alga Tasmanites, and an unidentified filmentous alga. It was found that IR spectra of the fossil algae, in common, contain intense aliphatic C-H stretching bands in the 2900-cm[sup [minus]1] region relative to the C=C stretching band at 1600 cm[sup [minus]1]. The carboxylic acid C=O stretching band at 1710 cm[sup [minus]1] is moderately intense. The relative intensities of these bands vary among the three different fossil algae. Maximum-likelihood spectral restoration and subsequent curve fitting of the stretching vibrations of the aliphatic C-H bands provide greater insight into the aliphatic structures of fossil algae. The CH[sub 2]/CH[sub 3] intensity ratio can be calculated and used to assess the relative average aliphatic chain length and the degree of branching. 29 refs., 10 figs., 1 tab.

Lin, R.; Ritz, G.P. (Unocal Science and Technology Division, Brea, CA (United States))

1993-03-01

52

Chemical structure of the organic matter in a Pliocene maar-type shale: Implicated Botryococcus race strains and formation pathways  

NASA Astrophysics Data System (ADS)

A maar-type Pliocene oil shale from Pula (Hungary) was examined by Scanning and Transmission Electron Microscopy (SEM, TEM) bitumen analysis, spectroscopic analyses (FTIR, solid state 13C NMR) and pyrolytic analyses of insoluble material. The investigated samples, corresponding to the "massive section" of Pula deposit, exhibit TOC values ranging from 18 to 42%, and Rock-Eval analysis indicated that such samples are comprised of low maturity type I kerogen. Electron Microscopy observations confirmed that recognizable microfossils in this organic matter-rich material almost exclusively correspond to Botryococcus braunii colonies, the morphology of which is perfectly retained. Identification of bitumen and pyrolysate constituents (hydrocarbons, ketones, fatty acids), along with morphological and spectroscopic features, indicate (1) that B. braunii provided a major input to the most organic matter-rich section of Pula oil shale; (2) that both the n-alkadienes-producing and the lycopadiene-producing strains ( A and L, respectively) were present; (3) that the selective preservation of the insoluble and non-hydrolysable macromolecules building up B. braunii outer walls was by far the main process in the formation of this material; (4) that such a process, along with B. braunii prolific growth in the favourable environment that occurred in the crater lake, accounts for the very high TOC and oil potential of Pula deposit; and (5) that the condensation of high molecular weight ether lipids from the A race and of some bacterial lipids also likely contributed to Pula kerogen formation.

Derenne, Sylvie; Largeau, Claude; Het幯yi, Magdolna; Brukner-Wein, Alice; Connan, Jacques; Lugardon, Bernard

1997-05-01

53

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)

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.

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

2000-11-01

54

Nitrate Reductase from Monoraphidium braunii: Immunocytochemical Localization and Immunological Characterization.  

PubMed

Homogeneous nitrate reductase (EC 1.6.6.2) from Monoraphidium braunii was obtained by means of affinity chromatography in blue-Sepharose and gel filtration. After electrophoresis in polyacrylamide, gel slices containing pure nitrate reductase were disrupted and injected into previously unimmunized rabbits. The antiserum produced after several weeks was found to inhibit the different activities of nitrate reductase to a similar degree. Monospecificity of the antiserum was demonstrated by Ouchterlony double diffusion and crossed immunoelectrophoresis. The antibodies were purified by immunoabsorption to Sepharose-bound nitrate reductase.The intracellular location of nitrate reductase in green algae was examined by applying an immunocytochemical method to M. braunii cells. Ultrathin frozen sections were first treated with immunopurified anti-nitrate reductase monospecific antibodies, followed by incubation with colloidal gold-labeled goat antirabbit immunoglobulin G as a marker. The enzyme was specifically located in the pyrenoid region of the chloroplast. PMID:16664292

Lopez-Ruiz, A; Roldan, J M; Verbelen, J P; Diez, J

1985-07-01

55

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)

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.

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

1994-09-01

56

Nitrate reductase of green algae is located in the pyrenoid.  

PubMed

Antibodies against nitrate reductase from Monoraphidium braunii have been used to determine the antigenic relationships of nitrate reductases from different green algae. Nitrate reductases from Chlamydomonas reinhardii, Chlorella fusca, Dunaliella salina, and Scenedesmus obliquus, were inhibited by, and cross-reacted with, antibodies raised against the enzyme from Monoraphidium braunii.These antibodies were also used to determine, by immunoelectron microscopy, the intracellular location of nitrate reductase in the aforementioned green algae. In all cases, the enzyme was specifically located in the pyrenoid. PMID:16664519

Lopez-Ruiz, A; Verbelen, J P; Roldan, J M; Diez, J

1985-12-01

57

Evaluation of extraction methods for recovery of fatty acids from Botryococcus braunii LB 572 and Synechocystis sp. PCC 6803  

Microsoft Academic Search

Microalgae are a very diverse group of organisms that consist in both prokaryotic and eukaryotic forms. Some species of microalgae\\u000a can be induced to overproduce particular fatty acids through simple manipulations of the physical and chemical properties\\u000a of the culture medium. In this paper, the effect of different extraction techniques on the recovery of fatty acids from the\\u000a freeze-dried biomass

Hai-Linh Tran; Seong-Joo Hong; Choul-Gyun Lee

2009-01-01

58

Limiting CO2 levels induce a blue light-dependent HCO3- uptake system in Monoraphidium braunii.  

PubMed

The in situ photoactivation of an HCO3- uptake system in the green alga Monoraphidium braunii requires the irradiation of the cell suspensions with short wavelength radiation (blue, UVA and/or UVC). Plasma membrane ATPase inhibitors block the uptake of this monovalent anion at pH 9. M. braunii cells grown in high CO2 lack an HCO3- uptake system in their plasma membrane, but those grown in low CO2 can take up this anion at high rates. Cells grown in high CO2, transferred to CO2-limiting conditions in the light, start taking up HCO3- in 30 min, although they take 90 min to reach maximum rates of HCO3- transport. Therefore, this induction process seems to be triggered by low external CO2 concentration. In fact, increasing or decreasing the external HCO3- concentration does not induce the uptake system and only a decrease in CO2 concentration in the medium triggers the induction process. The appearance of the HCO3- transport activity is sensitive to cycloheximide, indicating that cytoplasmic protein biosynthesis is necessary for the induction of the uptake system. Photosynthetically active radiation, but not particularly blue light, is essential for induction of the uptake system to occur and the inhibition of photosynthesis by DCMU blocks it. From these results it can be inferred that when M. braunii cells detect a drop in CO2 concentration, they induce a blue light-dependent HCO3- uptake system. PMID:10938873

Gir嫮dez, N; Aparicio, P J; Qui隳nes, M A

2000-04-01

59

Nitrate Reductase of Green Algae Is Located in the Pyrenoid 1  

PubMed Central

Antibodies against nitrate reductase from Monoraphidium braunii have been used to determine the antigenic relationships of nitrate reductases from different green algae. Nitrate reductases from Chlamydomonas reinhardii, Chlorella fusca, Dunaliella salina, and Scenedesmus obliquus, were inhibited by, and cross-reacted with, antibodies raised against the enzyme from Monoraphidium braunii. These antibodies were also used to determine, by immunoelectron microscopy, the intracellular location of nitrate reductase in the aforementioned green algae. In all cases, the enzyme was specifically located in the pyrenoid. Images Fig. 4 Fig. 5 Fig. 1 Fig. 3 Fig. 6

Lopez-Ruiz, Antonio; Verbelen, Jean Pierre; Roldan, Jose Manuel; Diez, Jesus

1985-01-01

60

Independent induction of two blue light-dependent monovalent anion transport systems in the plasma membrane of Monoraphidium braunii.  

PubMed

In the plasma membrane of the green alga Monoraphidium braunii there are at least two monovalent anion transport systems. One of them is specific for bicarbonate. This transport system is activated by blue light and its induction is triggered by a decrease in the external CO2 concentration. The second transport system is responsible for nitrate uptake at least. This transport system is also activated by blue light and its induction occurs when there is no ammonium in the external medium. Both transport systems are synthesized independently. Hence, when M. braunii cells grow with nitrate as the only nitrogen source under high CO2, they have a nitrate transport system but lack a bicarbonate transporter. Conversely, cells grown with ammonium under low CO2, have a bicarbonate transport system but lack a nitrate transporter. Both transport systems are induced in cells irradiated with white light in the absence of a carbon source, suggesting that there may be precursors in the plasma membrane that only need the synthesis and assembly of some component(s) to become fully active. The induction of nitrate and nitrite reductases, however, only takes place when a carbon source is supplied to the cells. PMID:12177130

Mora, Cristina; Witt, Federico G; Aparicio, Pedro J; Qui隳nes, Miguel A

2002-09-01

61

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

Microsoft Academic Search

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

Dinesh K. Barupal; Tobias Kind; Shankar L. Kothari; Do Yup Lee; Oliver Fiehn

2010-01-01

62

Antilipemic and hypocholesteremic activities of Globimetula braunii in rats.  

PubMed

Antilipemic/hypocholestermic activities of the methanolic extracts of Globimetula braunii were studied in the tissues of normo and hypercholesteremic rats. Hypercholesteremia was induced in the rats by feeding with dietary cholesterol at a dose of 40 mg/kg body weight. A significant increase (p<0.05) was observed in the body and the visceral organs relative weights in all the groups. There was a significant decrease in HDL-cholesterol and a significant increase in the levels of LDL, total cholesterol and triglycerides in hypercholesteremic rats when compared to normo rats. Administration of the methanolic extracts restored the elevated levels of serum lipids to normal. The methanolic extracts of G. braunii produced a significant (p<0.05) decrease in the levels of total cholesterol, triglyceride, LDL-cholesterol and lipid peroxidation of the extract treated group compared to hypercholesteremic control. There was a significant (p<0.05) increase in the levels of HDL-cholesterol as compared to hypercholesteremic control. The results obtained from this study are indications of the antilipemic and hypocholestermic activities of G. braunii as well as its cardio-protective potential in normo and hypercholesteremia conditions. PMID:20619620

Erukainure, Ochuko L; Abovwe, Joseph A; Adefegha, Adeniyi S; Egwuche, Rabiat U; Fafunso, Michael A

2010-07-09

63

Immunocytochemical localization of nitrite reductase in green algae.  

PubMed

The distribution of nitrite reductase (EC 1.7.7.1) in the green algae Chlamydomonas reinhardtii, Monoraphidium braunii, Chlorella fusca, and Scenedesmus obliquus was studied by immunoelectron microscopy. The labeling of ultrathin cryosections was performed with anti-nitrite reductase antibodies followed by gold-labeled goat anti-rabbit antibodies. In C. reinhardtii sections, gold label was mainly associated with the pyrenoid, tonoplast, and plasmalemma. Significant labeling was also detected in the thylakoid region. In all other organisms, label density was lower but distributed in the same locations, except that the plasmalemma of S. obliquus was not significantly labeled. From estimates of the relative volume of different cell regions, we found that approximately 80% of the total enzyme is located in the chloroplastic region (thylakoids plus pyrenoid) of C. reinhardtii, M. braunii, and C. fusca, and 97% in the case of S. obliquus. PMID:16668245

L鏕ez-Ruiz, A; Verbelen, J P; Bocanegra, J A; Diez, J

1991-07-01

64

Immunocytochemical Localization of Nitrite Reductase in Green Algae 1  

PubMed Central

The distribution of nitrite reductase (EC 1.7.7.1) in the green algae Chlamydomonas reinhardtii, Monoraphidium braunii, Chlorella fusca, and Scenedesmus obliquus was studied by immunoelectron microscopy. The labeling of ultrathin cryosections was performed with anti-nitrite reductase antibodies followed by gold-labeled goat anti-rabbit antibodies. In C. reinhardtii sections, gold label was mainly associated with the pyrenoid, tonoplast, and plasmalemma. Significant labeling was also detected in the thylakoid region. In all other organisms, label density was lower but distributed in the same locations, except that the plasmalemma of S. obliquus was not significantly labeled. From estimates of the relative volume of different cell regions, we found that approximately 80% of the total enzyme is located in the chloroplastic region (thylakoids plus pyrenoid) of C. reinhardtii, M. braunii, and C. fusca, and 97% in the case of S. obliquus. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5

Lopez-Ruiz, Antonio; Verbelen, Jean-Pierre; Bocanegra, Jose A.; Diez, Jesus

1991-01-01

65

Oxytocic properties of the aqueous extract of Globimetula braunii (loranthaceae).  

PubMed

The leaves of Globimetula braunii are used in ethnomedicine to augment labour. The crude aqueous extract of the plant was tested on isolated rat uteri. The agonistic activity of the aqueous extract was compared with that of a standard uterine stimulant oxytocin and uterine smooth muscle antagonists atropine and salbutamol. The extract was found to exhibit oxytocic activity on the uterine smooth muscle which was less potent than that of oxytocin. The force of contraction (3.60 +/-0.25 g) elicited by the highest concentration of the extract (640 mg/ ml) was similar to that of 2.7 x 10-4 mg / ml of oxytocin (3.61+/-0.17 g). Oxytocin was also observed to significantly (p<0.05) enhance the uterine contractile effect of the extract. The oxytocic effects of the extract was significantly (p<0.05) inhibited by both atropine and salbutamol. The oxytocic effects indicate the presence of active principle(s) which would explain the use of the leaves of Globimetula braunii to "hasten delivery" in traditional medicine practice. PMID:18930855

Ie, Oboh; Zam, Nworgu

2008-10-01

66

Similar morphological and chemical variations of Gloeocapsomorpha prisca in Ordovician sediments and cultured Botryococcus braunii as a response to changes in salinity  

Microsoft Academic Search

Most Ordovician source rocks consist of accumulation of a colonial marine microorganism, Gloeocapsomorpha prisca (G. prisca) whose nature, ecology and affinity with extant organisms have been in dispute for years. Furthermore, recent studies have shown major differences in phenol moieties between two G. prisca-rich samples. Examination of five G. prisca-rich kerogens by electron microscopy and pyrolysis studies revealed (i) the

J. S. Sinninghe Damst; S. Derenne; P. Metzger; C. Largeau; P. F. van Bergen; J. P. Gatellier; J. W. de Leeuw; C. Berkaloff

1992-01-01

67

Regulation of the O-acetyl-L-serine(thiol)lyase activity in Monoraphidium braunii.  

PubMed

Total level of O-acetyl-L-serine(thiol)lyase (OASTL) activity observed in Monoraphidium braunii fed-repleted cells decreases up to 40% after 24 h the carbon source was removed from the culture; however, no significant change in the activity is observed in N-starved cells. On the other hand, sulfur starvation induces OASTL activity in M. braunii, which may increase 2.5-fold after 36 h. Normal intracellular level of the activity is restored when a sulfur source, such as sulfate, sulfite, L-cysteine, L-methionine or glutathione is added to the culture. The induction of the OASTL activity requires de novo synthesis of protein, and thus the presence in the culture of adequate carbon and nitrogen sources. The OASTL isoenzymes from M. braunii cells are differently affected by S-starvation. PMID:10217210

Gonz嫮ez-Arroyo, J G; Vega, J M; P廨ez-Casti鎑ira, J R

1998-09-01

68

Cytochrome c6 from Monoraphidium braunii. A cytochrome with an unusual heme axial coordination.  

PubMed

A soluble monoheme c-type cytochrome (cytochrome c6) has been isolated from the green alga Monoraphidium braunii. It has a molecular mass of 9.3 kDa, an isoelectric point of 3.6 and a reduction potential of 358 mV at pH 7. The determined amino acid sequence allows its classification as a class-I c-type cytochrome. The ferric and ferrous cytochrome forms and their pH equilibria have been studied using 1H-NMR, ultraviolet/visible, EPR and M飉sbauer spectroscopies. The pH equilibria are complex, several pKa values and pH-dependent forms being observed. The amino acid sequence, the reduction-potential value and the visible and NMR spectroscopies data in the pH range 4-9 indicate that the heme iron has a methionine-histidine axial coordination. However, the EPR and M飉sbauer data obtained for the ferricytochrome show that in this pH range two distinct forms are present: form I, gz = 3.27, gy = 2.05 and gx = 1.05; form II, gz = 2.95, gy = 2.29 and gx = 1.43. While form I has crystal-field parameters typical of a methionine-histidine coordination, those associated with form II would suggest a histidine-histidine axial ligation. This possibility was extensively analyzed by spectroscopic methods and by chemical modification of a histidine residue. It was concluded that form II actually corresponds to an unusual type of methionine-histidine axial coordination. Straightforward examples of this type of coordination have recently been found in other c-type hemeproteins [Teixeira, M., Campos, A. P., Aguiar, A. P., Costa, H. S., Santos, H., Turner, D. L. & Xavier, A. V. (1993) FEBS Lett. 317, 233-236], corroborating our proposal. Since both forms, with very distinct crystal-field parameters, are shown to have the same reduction potential, it may be concluded that the axial and rhombic distortions of the heme-iron ligand field cannot be directly correlated with the heme-reduction potential. The pH-dependence studies have also shown that the form I and form II are interconvertible, with pKa approximately 5. To establish a possible physiological significance for this process, in particular for the interaction of the cytochrome with the membrane-bound electron-transfer complexes b6f and photosystem I, the effect of surfactants on the spectroscopic characteristics of cytochrome c6 has been studied. PMID:8396033

Campos, A P; Aguiar, A P; Herv嫳, M; Regalla, M; Navarro, J A; Ortega, J M; Xavier, A V; De La Rosa, M A; Teixeira, M

1993-08-15

69

The Study of Algae  

ERIC Educational Resources Information Center

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

Rushforth, Samuel R.

1977-01-01

70

Purification and characterization of cytochrome c6 from the unicellular green alga Scenedesmus obliquus.  

PubMed

Purification of a soluble cytochrome c6 from the unicellular green alga Scenedesmus obliquus by a simple and rapid method is described. The purification procedure includes ammonium sulfate precipitation and non-denaturating PAGE. The N-terminal sequence of the first 20 amino acids was determined and shows 85% similarity and 75% identity to the sequence of cytochrome c6 from the green alga Monoraphidium braunii. The ferrocytochrome shows typical UV/VIS absorption peaks at 552.9, 521.9 and 415.7 nm. The apparent molecular mass was estimated to be 12 kDa by SDS-PAGE. EPR-spectroscopy at 20 K shows resonances indicative for two distinct low-spin heme forms. PMID:9463935

Wnschiers, R; Zinn, T; Linder, D; Schulz, R

71

Loliolide in marine algae.  

PubMed

Loliolide content was determined in 13 marine algae including red, brown and green algae collected from the Black Sea, the Dardanelles and the Aegean Sea. Identification and quantification were performed by gas chromatography-mass spectrometry. The loliolide content in green alga is 1.76 microg g(-1), ranges from 0.14 to 4.35 microg g(-1) in red and from 0.18 to 4.83 microg g(-1) in brown algae. The results obtained are in the same range as previously reported for algae, as well as terrestrial plants. This article represents the first report of loliolide occurrence in green algae. PMID:19296390

Percot, Aline; Yalcin, Ahmet; Aysel, Veysel; Erdu?an, Hseyin; Dural, Berrin; Gven, Kasim Cemal

2009-01-01

72

Granulados biocl嫳ticos: algas calc嫫ias  

Microsoft Academic Search

Os granulados biocl嫳ticos marinhos, no Brasil, s緌 formados principalmente por algas calc嫫ias (Maerl e Lithothamnium, na Fran蓷). Apenas as formas livres (free-living) das algas calc嫫ias, tais como rodolitos, n鏚ulos, e seus fragmentos, s緌 vi嫛eis para a explora誽o econ獽ica, pois constituem dep鏀itos sedimentares inconsolidados, facilmente coletados atrav廥 de dragagens. As algas calc嫫ias s緌 compostas basicamente por carbonato de c嫮cio e carbonato

Gilberto T. M. Dias

2000-01-01

73

Alkaloids in Marine Algae  

PubMed Central

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.

Guven, Kas?m Cemal; Percot, Aline; Sezik, Ekrem

2010-01-01

74

Immunological approach to the regulation of nitrate reductase in Monoraphidium braunii.  

PubMed

The effects of different culture conditions on nitrate reductase activity and nitrate reductase protein from Monoraphidium braunii have been studied, using two different immunological techniques, rocket immunoelectrophoresis and an enzyme-linked immunosorbent assay, to determine nitrate reductase protein. The nitrogen sources ammonium and glutamine repressed nitrate reductase synthesis, while nitrite, alanine, and glutamate acted as derepressors. There was a four- to eightfold increase of nitrate reductase activity and a twofold increase of nitrate reductase protein under conditions of nitrogen starvation versus growth on nitrate. Nitrate reductase synthesis was repressed in darkness. However, when Monoraphidium was grown under heterotrophic conditions with glucose as the carbon and energy source, the synthesis of nitrate reductase was maintained. With ammonium or darkness, changes in nitrate reductase activity correlated fairly well with changes in nitrate reductase protein, indicating that in both cases loss of activity was due to repression and not to inactivation of the enzyme. Experiments using methionine sulfoximine, to inhibit ammonium assimilation, showed that ammonium per se and not a product of its metabolism was the corepressor of the enzyme. The appearance of nitrate reductase activity after transferring the cells to induction media was prevented by cycloheximide and by 6-methylpurine, although in this latter case the effect was observed only in cells preincubated with the inhibitor for 1 h before the induction period. PMID:2913954

D獯z, J; L鏕ez-Ruiz, A

1989-02-01

75

Characterization of the Reversible Inactivation of Ankistrodesmus braunii Nitrate Reductase by Hydroxylamine 1  

PubMed Central

The photoreversible nature of the regulation of nitrate reductase is one of the most interesting features of this enzyme. As well as other chemicals, NH2OH reversibly inactivates the reduced form of nitrate reductase from Ankistrodesmus braunii. From the partial activities of the enzyme, only terminal nitrate reductase is affected by NH2OH. To demonstrate that the terminal activity was readily inactivted by NH2OH, the necessary reductants of the terminal part of the enzyme had to be cleared of dithionite since this compound reacts chemically with NH2OH. Photoreduced flavins and electrochemically reduced methyl viologen sustain very effective inactivation of terminal nitrate reductase activity, even if the enzyme was previously deprived of its NADH-dehydrogenase activity. The early inhibition of nitrate reductase by NH2OH appears to be competitive versus NO3?. Since NO3?, as well as cyanate, carbamyl phosphate and azide (competitive inhibitors of nitrate reductase versus NO3?), protect the enzyme from NH2OH inactivation, it is suggested that NH2OH binds to the nitrate active site. The NH2OH-inactivated enzyme was photoreactivated in the presence of flavins, although slower than when the enzyme was previously inactivated with CN?. NH2OH and NADH concentrations required for full inactivation of nitrate reductase appear to be low enough to potentially consider this inactivation process of physiological significance.

Balandin, Teresa; Fernandez, Victor M.; Aparicio, Pedro J.

1986-01-01

76

Genetically Modified Bacteria for Fuel Production: Development of Rhodobacteria as a Versatile Platform for Fuels Production  

SciTech Connect

Electrofuels Project: Penn State is genetically engineering bacteria called Rhodobacter to use electricity or electrically generated hydrogen to convert carbon dioxide into liquid fuels. Penn State is taking genes from oil-producing algae called Botryococcus braunii and putting them into Rhodobacter to produce hydrocarbon molecules, which closely resemble gasoline. Penn State is developing engineered tanks to support microbial fuel production and determining the most economical way to feed the electricity or hydrogen to the bacteria, including using renewable sources of power like solar energy.

None

2010-07-01

77

Temporal variability of dissolved P speciation in a eutrophic reservoir--implications for predicating algal growth.  

PubMed

Weak-anion exchange chromatography was used to explore the temporal variability in the speciation of dissolved P in the surface layer of a eutrophic reservoir. Authentic free ortho-P ion was the most common form of P on three of the five sampling occasions-including during a bloom of the green algae Botryococcus braunii indicating that the bloom was not P limited. Conversely, the absence of authentic ortho-P during a bloom of the dinoflagellate Ceratium hirundinella suggested the bloom was either P limited or co-limited. These observations were confirmed by algal-growth bioassay experiments. PMID:14568044

Baldwin, D S; Whittington, J; Oliver, R

2003-11-01

78

Molecular composition and mobility of torbanite precursors: Implications for the structure of coal  

USGS Publications Warehouse

Coorongite, a torbanite precursor found in South Australia, and algal residues derived from Botryococcus braunii and other algae have been examined by solid-state 13C NMR techniques. The majority of carbon in these materials is present as (CH2)n. However, variable-temperature studies show that a considerable proportion of the alkyl chains have unusual dipolar-dephasing behavior and are more mobile than in rigid solids. It is suggested that these mobile structures contribute to the so-called "guest phases" in coal. The data are also consistent with a vascular and algal model of coal. ?? 1988 American Chemical Society.

Wilson, M. A.; Batts, B. D.; Hatcher, P. G.

1988-01-01

79

[Harmful algae and health].  

PubMed

Harmful algae are a worldwide problem. Phycotoxins is a general term for toxic compounds produced by harmful species of the phytoplankton. This review deals with the occurrence of harmful algae and phycotoxins in the Baltic Sea and other domestic waters, the ways of getting exposed to them, and their effects. Advice on how to avoid the exposure is provided. PMID:21834336

Kankaanp鳵, Harri T

2011-01-01

80

Algae Removal by Flotation  

Microsoft Academic Search

\\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

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

81

Biotechnology of Algae: A Bibliography.  

National Technical Information Service (NTIS)

The use of algae in biotechnology research and in the biotechnology industry is significant. Algae play critical roles as bioreactors for the production of food, chemicals, and fuels. They are becoming extremely important in the development of solar energ...

V. Stone R. D. Warmbrodt A. T. Young

1993-01-01

82

Supercritical carbon dioxide extraction of compounds with pharmaceutical importance from microalgae  

Microsoft Academic Search

Four microalgae (Botryococcus braunii, Chlorella vulgaris, Dunaliella salina, Arthrospira maxima) were object of supercritical CO2 extraction studies, which were carried out in a flow apparatus at temperatures between 313.1 and 333.1 K and pressures up to 35.0 MPa. The microalga Botryococcus braunii produces extracellular alkadienes. Supercritical extracts obtained at 313.1 K, and pressures of 12.5, 20.0 and 30.0 MPa, were

Rui L. Mendes; Beatriz P. Nobre; Miguel T. Cardoso; Ana P. Pereira; Ant鏮io F. Palavra

2003-01-01

83

Ecology of Harmful Algae  

Microsoft Academic Search

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

Daniel L. Roelke

2007-01-01

84

Algae in Animal Production  

Microsoft Academic Search

Summary In the context of threats to fragile environments, there is a need in animal production to identify alternative feed resources, which are environmentally friendly, but at the same time utilize natural resources efficiently. Algae are autotrophic organisms, which have potentia as food and feed for man and animals. They are rich in protein (50-60%), lipids (2-22%), vitamins and

S. A. Chowdhury; K. S. Huque; M. Khatun

85

Algae fuel clean electricity generation  

Microsoft Academic Search

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

1993-01-01

86

Miocene Coralline algae  

SciTech Connect

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.

Bosence, D.W.J.

1988-01-01

87

The resource utilization of algaePreparing coal slurry with algae  

Microsoft Academic Search

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 coalalgae slurry. Coal slurries prepared with algae were investigated, and gasification reactivity of coalalgae slurry was compared with that of

Weidong Li; Weifeng Li; Haifeng Liu

2010-01-01

88

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

PubMed

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

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

2004-12-01

89

Neuroprotective Effects of Marine Algae  

PubMed Central

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.

Pangestuti, Ratih; Kim, Se-Kwon

2011-01-01

90

Formation of Algae Growth Constitutive Relations for Improved Algae Modeling.  

National Technical Information Service (NTIS)

This SAND report summarizes research conducted as a part of a two year Laboratory Directed Research and Development (LDRD) project to improve our abilities to model algal cultivation. Algae-based biofuels have generated much excitement due to their potent...

J. L. Drewry P. E. Gharagozloo

2013-01-01

91

Algae fuel clean electricity generation  

SciTech Connect

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

O'Sullivan, D.

1993-02-08

92

MONOTERPENE BIOSYNTHESIS IN MARINE ALGAE  

Technology Transfer Automated Retrieval System (TEKTRAN)

Marine algae produce a variety of secondary metabolites involved in chemical defense. Among these the monoterpenes present several highly unusual characteristics relative to their terrestrial counterparts. The monoterpenes produced by these marine organisms are nearly always halogenated and posses...

93

F-LE Algae Blooms  

NSDL National Science Digital Library

This is a task from the Illustrative Mathematics website that is one part of a complete illustration of the standard to which it is aligned. Each task has at least one solution and some commentary that addresses important asects of the task and its potential use. Here are the first few lines of the commentary for this task: Algae blooms routinely threaten the health of the Chesapeake Bay. Phosphate compounds supply a rich source of nutrients for the algae, Prorocentrum min...

94

Ultrahigh bioproductivity from algae.  

PubMed

The potential for dramatic increases in bioproductivity in algal photobioreactors relative to current biomass approaches, e.g., for converting sunlight into biofuels, by an unorthodox integration of photonics and biotechnologies is described. The key to greater biomass yields--projected as high as 100 g dry weight m(-2) h(-1)-is a pronounced heightening of algal flux tolerance, achieved by tailoring the photonic temporal, spectral and intensity characteristics with pulsed light-emitting diodes. Such tailored photonic input is applied in concert with thin-channel ultradense culture photobioreactors with flow patterns that produce rapid light/dark algae exposure cycles. The artificial-light scheme is globally feasible only with electricity generated from renewables. Recent advances in ultra-efficient concentrator photovoltaics, as well as high-performance light-emitting diodes, create a practical reality for converting sunlight into pulsed red light and delivering it to indoor photobioreactors, with characteristic pulse times and intensities optimally suited to the rate-limiting dark reactions of photosynthesis. Cellular engineering built upon recent progress in modifying algal chlorophyll antenna size, in combination with metabolic engineering, could further enhance bioproductivity. The proposed strategy requires no major advances for implementation and adopts existing technologies. PMID:17646982

Gordon, Jeffrey M; Polle, Juergen E W

2007-07-24

95

21 CFR 184.1120 - Brown algae.  

Code of Federal Regulations, 2010 CFR

...RECOGNIZED AS SAFE Listing of Specific Substances Affirmed as GRAS 禮 184.1120 Brown algae. (a) Brown algae are seaweeds of the species Analipus japonicus, Eisenia bicyclis, Hizikia fusiforme, Kjellmaniella gyrata, Laminaria...

2010-01-01

96

21 CFR 184.1120 - Brown algae.  

Code of Federal Regulations, 2010 CFR

...Substances Affirmed as GRAS 禮 184.1120 Brown algae. (a) Brown algae are seaweeds of the species Analipus japonicus, Eisenia bicyclis, Hizikia fusiforme, Kjellmaniella gyrata, Laminaria angustata, Laminaria claustonia, Laminaria...

2009-04-01

97

Microscopic Gardens: A Close Look at Algae.  

ERIC Educational Resources Information Center

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

Foote, Mary Ann

1983-01-01

98

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

NASA Astrophysics Data System (ADS)

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.

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

2000-06-01

99

Notes from the Iberian Algae Belt  

Microsoft Academic Search

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

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

2011-01-01

100

Indigenous algae for local bioresource production: Phycoprospecting  

Microsoft Academic Search

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

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

101

21 CFR 184.1121 - Red algae.  

Code of Federal Regulations, 2010 CFR

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

2009-04-01

102

21 CFR 184.1121 - Red algae.  

Code of Federal Regulations, 2010 CFR

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

2010-01-01

103

Carbon monoxide production by algae  

Microsoft Academic Search

Carbon monoxide production has been demonstrated in Egregia menzies, several other algae and in the higher plants, Zostera marina and Medicago saliva. The ability to produce carbon monoxide is not destroyed by heating the tissues. Oxygen is required for carbon monoxide production by Egregia menzies. A carbon monoxide-producing compound can be extracted by refluxing the macerated algal tissues in 0.01

M. W. Loewus; C. C. Delwiche

1963-01-01

104

Algae. LC Science Tracer Bullet.  

ERIC Educational Resources Information Center

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

Niskern, Diana, Comp.

105

Glycolate Pathway in Algae 1  

PubMed Central

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.

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

1967-01-01

106

Recycling nutrients in algae biorefinery.  

PubMed

Algal fuel cells: Repeated nutrient recycling is demonstrated by reusing the aqueous phase obtained from the hydrothermal liquefaction (HTL) of microalgae. This is achieved, for the first time, by performing a complete set of four continuous growth-HTL cycles. Results show similar growth rates in each cycle, the potential of nutrient reduction, as well as cell morphology changes. This study demonstrates progress towards the standalone operation of algae biorefineries. PMID:23828814

Garcia Alba, Laura; Vos, Mathijs P; Torri, Cristian; Fabbri, Daniele; Kersten, Sascha R A; Brilman, Derk W F

2013-07-04

107

Algae control for hydrogeneration canals  

SciTech Connect

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.

Grahovac, P.

1997-02-16

108

The cytoskeleton of chromophyte algae  

Microsoft Academic Search

Summary The cytoskeleton of flagellate chromophyte algae, zoospores and gametes is active during swimming, phototaxis, several types of phagotrophic feeding, the formation, secretion and deployment of silica-scales, and the abrupt movement of spine-scales. The flagellar basal bodies are anchored by microtubular roots and\\/or fibrous roots. The kinds, numbers, and paths of these roots are characteristic of different taxonomic groups within

R. A. Andersen

1991-01-01

109

Importance of algae oil as a source of biodiesel  

Microsoft Academic Search

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

Ayhan Demirbas; M. Fatih Demirbas

2011-01-01

110

The systematics and ecology of soil algae  

Microsoft Academic Search

SummaryAlgae occur in nearly all terrestrial environments on earth and are invariably encountered both on and beneath soil surfaces.\\u000a The algal flora of the soil includes members of the Cyanochloronta, Chlorophycophyta, Euglenophycophyta, Chrysophycophyta,\\u000a and Rhodophycophyta. Thirty-eight genera of prokaryotic and 147 genera of eukaryotic algae include terrestrial species, the\\u000a majority of which are edaphic. Whereas systematic nomenclature of blue-green algae

Blaine Metting

1981-01-01

111

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

Microsoft Academic Search

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.

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

112

21 CFR 73.185 - Haematococcus algae meal.  

Code of Federal Regulations, 2010 CFR

...2009-04-01 false Haematococcus algae meal. 73.185 Section 73.185...CERTIFICATION Foods 禮 73.185 Haematococcus algae meal. (a) Identity. (1) The color additive haematococcus algae meal consists of the comminuted and...

2009-04-01

113

21 CFR 73.185 - Haematococcus algae meal.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Haematococcus algae meal. 73.185 Section 73.185...CERTIFICATION Foods 禮 73.185 Haematococcus algae meal. (a) Identity. (1) The color additive haematococcus algae meal consists of the comminuted and...

2010-04-01

114

21 CFR 73.185 - Haematococcus algae meal.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Haematococcus algae meal. 73.185 Section 73.185...CERTIFICATION Foods 禮 73.185 Haematococcus algae meal. (a) Identity. (1) The color additive haematococcus algae meal consists of the comminuted and...

2013-04-01

115

Lipids and lipid metabolism in eukaryotic algae  

Microsoft Academic Search

Eukaryotic algae are a very diverse group of organisms which inhabit a huge range of ecosystems from the Antarctic to deserts. They account for over half the primary productivity at the base of the food chain. In recent years studies on the lipid biochemistry of algae has shifted from experiments with a few model organisms to encompass a much larger

Irina A. Guschina; John L. Harwood

2006-01-01

116

Use of algae as biofuel sources  

Microsoft Academic Search

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

Ayhan Demirbas

2010-01-01

117

Effect of Dead Algae on Soil Permeability  

SciTech Connect

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

Harvey, R.S.

2003-02-21

118

Do diatom algae frustules accumulate uranium?  

Microsoft Academic Search

Neutron Activation Analysis (NAA) and Synchrotron Radiation X-ray Fluorescent Analysis (SRXRFA) were used to measure the content of uranium and a few other trace elements in samples of bottom sediments of Lake Baikel separated into biogenic (diatom algae frustules) and clastic components by an aerodynamic method. Uranium is rejected, rather than accumulated by diatom algae frustules.

E. L. Goldberg; M. A. Grachev; V. A. Bobrov; A. V. Bessergenev; B. V. Zolotaryov; Ye. V. Likhoshway

1998-01-01

119

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...

120

SSMILes: Measuring the Nutrient Tolerance of Algae.  

ERIC Educational Resources Information Center

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

Hedgepeth, David J.

1995-01-01

121

Take a Dip! Culturing Algae Is Easy.  

ERIC Educational Resources Information Center

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

James, Daniel E.

1983-01-01

122

Hydrogen metabolism of photosynthetic bacteria and algae  

SciTech Connect

The metabolism, metabolic pathways and biochemistry of hydrogen in photosynthetic bacteria and algae are reviewed. Detailed information on the occurrence and measurement of hydrogenase activity is presented. Hydrogen production rates for different species of algae and bacteria are presented. 173 references, 1 figure, 7 tables.

Kumazawa, S.; Mitsui, A.

1982-01-01

123

Streptophyte algae and the origin of embryophytes  

PubMed Central

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 with branching, cell differentiation and apical growth (Charales). Streptophyte algae and embryophytes form the division Streptophyta, whereas the remaining green algae are classified as Chlorophyta. The Charales (stoneworts) are often considered to be sister to land plants, suggesting progressive evolution towards cellular complexity within streptophyte green algae. Many cellular (e.g. phragmoplast, plasmodesmata, hexameric cellulose synthase, structure of flagellated cells, oogamous sexual reproduction with zygote retention) and physiological characters (e.g. type of photorespiration, phytochrome system) originated within streptophyte algae. Recent Progress Phylogenetic studies have demonstrated that Mesostigma (flagellate) and Chlorokybus (sarcinoid) form the earliest divergence within streptophytes, as sister to all other Streptophyta including embryophytes. The question whether Charales, Coleochaetales or Zygnematales are the sister to embryophytes is still (or, again) hotly debated. Projects to study genome evolution within streptophytes including protein families and polyadenylation signals have been initiated. In agreement with morphological and physiological features, many molecular traits believed to be specific for embryophytes have been shown to predate the Chlorophyta/Streptophyta split, or to have originated within streptophyte algae. Molecular phylogenies and the fossil record allow a detailed reconstruction of the early evolutionary events that led to the origin of true land plants, and shaped the current diversity and ecology of streptophyte green algae and their embryophyte descendants. Conclusions The Streptophyta/Chlorophyta divergence correlates with a remarkably conservative preference for freshwater/marine habitats, and the early freshwater adaptation of streptophyte algae was a major advantage for the earliest land plants, even before the origin of the embryo and the sporophyte generation. The complete genomes of a few key streptophyte algae taxa will be required for a better understanding of the colonization of terrestrial habitats by streptophytes.

Becker, Burkhard; Marin, Birger

2009-01-01

124

21 CFR 73.275 - Dried algae meal.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Dried algae meal. 73.275 Section 73.275 Food...CERTIFICATION Foods 禮 73.275 Dried algae meal. (a) Identity. The color additive dried algae meal is a dried mixture of algae...

2010-04-01

125

21 CFR 73.275 - Dried algae meal.  

Code of Federal Regulations, 2010 CFR

...2009-04-01 2009-04-01 false Dried algae meal. 73.275 Section 73.275 Food...CERTIFICATION Foods 禮 73.275 Dried algae meal. (a) Identity. The color additive dried algae meal is a dried mixture of algae...

2009-04-01

126

Tetraprenyltoluquinols from the brown alga Cystophora fibrosa.  

PubMed

Six cyclised tetraprenyltoluquinols and five stereoisomers with the previously reported amentol skeleton have been isolated from the lipophilic extract of the South African brown alga Cystophora fibrosa. Structures and relative stereochemistry were determined using spectrometric techniques, particularly 1D and 2D NMR, and molecular modelling experiments. The compounds isolated appear to be enantiomeric to compounds with the same skeleton isolated from brown algae of the genus Cystoseira collected in northern Africa and the Mediterranean Sea. The isolation of tetraprenyltoluquinols with the amentol skeleton from this alga suggests that C. fibrosa should be moved from the genus Cystophora into the Cystoseira. PMID:16678228

Laird, Damian W; van Altena, Ian A

2006-05-05

127

Biosynthesis of 3-Dimethylsulfoniopropionate in Marine Algae.  

National Technical Information Service (NTIS)

To participate in a 4-investigator collaboration (Hanson, Gage, Leustek, Rhodes) to elucidate the pathway of 3- dimethylsulfonipropionate (DMSP) in marine algae, including identification of intermediates and enzymes of the pathway in the macroalgae Entero...

D. Rhodes

2000-01-01

128

Culture Methods for Selected Crustacea and Algae.  

National Technical Information Service (NTIS)

The report describes the methodologies used at the Great Lakes Fishery Laboratory for culturing certain crustacea, used in experimental studies, as well as culturing algae and other organisms used as food for crustacea. Although some of the techniques are...

B. S. Walters D. F. Berry A. Novak D. R. May Passino

1981-01-01

129

Aerobic Decomposition of Algae and Nutrient Regeneration.  

National Technical Information Service (NTIS)

This study presents definitive hypotheses for natural aerobic algal decomposition and nutrient regeneration. Emphasis is placed on the significance of the refractory organic fraction of algae in the decay and nutrient regeneration processes. Other variabl...

W. J. Jewell P. L. McCarty

1968-01-01

130

Collection, Isolation and Culture of Marine Algae.  

ERIC Educational Resources Information Center

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

James, Daniel E.

1984-01-01

131

The Algae and their General Characteristics  

Microsoft Academic Search

\\u000a In contrast to the land plants, algae have very diverse mechanisms of photosynthesis, and especially of light- harvesting\\u000a pigments and assemblages. This diversity is inherited from a great diversity of plastid types with different evolutionary\\u000a histories, not withstanding the fact that all plastids appear to be derived by endosymbiosis from Cyanobacteria or their forebears.\\u000a The major groups of algae are

Susan E. Douglas; John A. Raven; Anthony W. D. Larkum

132

Interactions between arsenic species and marine algae  

Microsoft Academic Search

The arsenic concentration and speciation of marine algae varies widely, from 0.4 to 23 ng.mg鄞, with significant differences in both total arsenic content and arsenic speciation occurring between algal classes. The Phaeophyceae contain more arsenic than other algal classes, and a greater proportion of the arsenic is organic. The concentration of inorganic arsenic is fairly constant in macro-algae, and may

1978-01-01

133

Carbohydrate Metabolism and Respiration in Algae  

Microsoft Academic Search

\\u000a Carbohydrates and their immediate derivatives have a number of roles related to photosynthesis in algae (including Cyanobacteria).\\u000a In the form of phosphorylated sugars, carbohydrates are major intermediates in the photosynthetic carbon reduction cycle and\\u000a the photorespiratory carbon oxidation cycle. Carbohydrates are common energy and carbon storage products in algae, permitting\\u000a imbalances between the rate of reduced carbon production in photosynthesis

John A. Raven; John Beardall

134

Antioxidant activity of Hawaiian marine algae.  

PubMed

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

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

2012-02-15

135

Antioxidant Activity of Hawaiian Marine Algae  

PubMed Central

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

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

2012-01-01

136

SCALE FORMATION IN CHRYSOPHYCEAN ALGAE  

PubMed Central

The cell wall of the marine chrysophycean alga Pleurochrysis scherfellii is composed of distinct wall fragments embedded in a gelatinous mass. The latter is a polysaccharide of pectic character which is rich in galactose and ribose. These wall fragments are identified as scales. They have been isolated and purified from the vegetative mother cell walls after zoospore formation. Their ultrastructure is described in an electron microscope study combining sectioning, freeze-etch, and negative staining techniques. The scales consist of a layer of concentrically arranged microfibrils (ribbons with cross-sections of 12 to 25 x 25 to 40 A) and underlying radial fibrils of similar dimensions. Such a network-plate is densely coated with particles which are assumed to be identical to the pectic component. The microfibrils are resistant to strong alkaline treatment and have been identified as cellulose by different methods, including sugar analysis after total hydrolysis, proton resonance spectroscopical examination (NMR spectroscopy) of the benzoylated product, and diverse histochemical tests. The formation and secretion of the scales can be followed along the maturing Golgi cisternae starting from a pronounced dilated "polymerization center" as a completely intracisternal process which ends in the exocytotic extrusion of the scales. The scales reveal the very same ultrastructure within the Golgi cisternae as they do in the cell wall. The present finding represents the first evidence on cellulose formation by the Golgi apparatus and is discussed in relation to a basic scheme for cellulose synthesis in plant cells in general.

Brown, R. Malcolm; Franke, Werner W.; Kleinig, Hans; Falk, Heinz; Sitte, Peter

1970-01-01

137

Possible algal origin of long chain odd n-alkanes in immature sediments as revealed by distributions and carbon isotope ratios  

Microsoft Academic Search

A Pliocene oil shale (Pula, Hungary), a C 3 plant Triticum aestivum and a C 4 plant Zea mays were compared using isotopic composition of bulk organic matter, along with distributions and individual carbon isotope ratios of n-alkanes from organic extracts. The microalga Botryococcus braunii (A race) was thus shown to be the main source of the predominant 27, 29

E LICHTFOUSE; SYLVIE DERENNE; ANDR MARIOTTI; C LARGEAU

1994-01-01

138

Chemical characterization of torbanites by transmission micro-FTIR spectroscopy: Origin and extent of compositional heterogeneities  

Microsoft Academic Search

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

Patrick Landais; A騃ha Rochdi; Claude Largeau; Sylvie Derenne

1993-01-01

139

Systems and economic analysis of microalgae ponds for conversion of CO{sub 2} to biomass. Fourth quarterly technical progress report, June 16, 1994--September 15, 1994  

SciTech Connect

The threat of global warming, mounting concerns about air and water pollution, prospective food shortages, and declining reserves of low-cost fossil fuels, have spawned a burgeoning interest in photobiological processes using microalgae as a method of large-scale utilization of CO{sub 2} for the production of fuels, food, and waste treatment. The major activity during this quarter was the development of cost data for the algal production system, including alternatives to the basic design previously used. The results of this work are still being developed and will be reported in the Final Report. This progress report summarizes a study of a production processes for one specific alga, Botryococcus braunii. This alga is of particular interest in this project as it produces an almost pure hydrocarbon fuel, and does so in rather large amounts. Technology for the production of this organism has, however, not yet been developed. This progress report reviews the literature on this interesting alga and suggests potential methods for its production. 62 refs.

Benemann, J.R.; Oswald, W.J.

1994-12-28

140

Genome of the red alga Porphyridium purpureum.  

PubMed

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

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; Z酳ner, Simone; Morath, Shannon; Hilliou, Fr嶮廨ique; Egizi, Andrea; Perrineau, Marie-Mathilde; Yoon, Hwan Su

2013-01-01

141

[Advances on the genome of algae].  

PubMed

Algae possess complex and diverse biology and evolutionary history. They play an important role in the ecosystem. A mass of unique genes and biological processes also make them attractive. The application of high-throughput sequencing approaches to algal research has greatly contributed to the development of algal genomics and transcriptomics, as well as enriched the gene information of algae. In this article, we summarize the advances of algal genomics and transcriptomics, describe and compare the characteristics of different algae genomes, and introduce the application of expression sequence tags (ESTs), microarray and RNA sequencing technique to algal transcriptomics research. Furthermore, the advances of algal gene expression and small RNA are also reviewed in detail. At last, we discuss the challenges and future development of this area. PMID:23774018

Lai, Xiao-Juan; Chen, Hai-Min; Yang, Rui; Yan, Xiao-Jun

2013-06-01

142

Acid Mine Drainage Treatment Utilizing Blue-Green Algae.  

National Technical Information Service (NTIS)

Preliminary studies suggested that freshwater algae accumulate relatively large concentrations of iron and manganese from AMD. A wetland was designed and constructed to treat a discharge from an abandoned deep mine to examine algae's ability to accumulate...

D. A. Kepler

1989-01-01

143

Use of Brown Algae to Demonstrate Natural Products Techniques.  

ERIC Educational Resources Information Center

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

Porter, Lee A.

1985-01-01

144

Uptake and Distribution of Technetium in Several Marine Algae.  

National Technical Information Service (NTIS)

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 concentra...

S. Bonotto G. B. Gerber C. T. Garten C. M. Vandecasteele C. Myttenaere

1983-01-01

145

ROLE OF SYMBIOTIC ALGAE (ZOOXANTHELLAE) IN CORAL CALCIFICATION  

Microsoft Academic Search

Members of many invertebrate groups live symbiotically with unicellular algae, but the symbiosis between corals amid dinoflagellate algae (zooxanthelhae) is espe cially interesting because it occurs in all species of tropical reef-buildimig corals ( see reviews by Droop, 1963 ; Yonge, 1963 ; McLaughlin and Zahl, 1966) . Moreover, a significant effect of the algae om-m time physiology of corals

VICKI BUCHSBAUM; LEONARD MUSCATINE

146

Development of suitable photobioreactor for algae production A review  

Microsoft Academic Search

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

R. N. Singh; Shaishav Sharma

2012-01-01

147

Determination of elements in algae by different atomic spectroscopic methods  

Microsoft Academic Search

The chemistry of substances derived from plants has received a great deal of attention in the last several decades. Today, natural products and their synthetic analogs also play an important role in the pharmaceutical and food industry. Several interesting reviews on algae were published in the last 10 years. Algae, especially the red algae, are very helpful in every day

Anna Csikkel-Szolnoki; M嫫ia B嫢hori; Gerald Blunden

2000-01-01

148

The origin of red algae and the evolution of chloroplasts  

Microsoft Academic Search

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

David Moreira; Herv Le Guyader; Herv Philippe

2000-01-01

149

Method for cultivating algae and a covering material used therefor  

US Patent & Trademark Office Database

A method for cultivating an alga, which comprises growing the alga in a light field substantially free from light of wavelengths of not more than 340 nm; and a covering material for use in the cultivation of algae, said covering material substantially inhibiting the transmission of light of wavelengths of not more than 340 nm.

Harasawa; Isamu (Kiyose, JP); Hariki; Yukio (Funabashi, JP); Maeda; Katsuhiko (Uozu, JP); Nakamura; Kouichi (Uozu, JP)

1980-11-25

150

How to Identify and Control Water Weeds and Algae.  

ERIC Educational Resources Information Center

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

Applied Biochemists, Inc., Mequon, WI.

151

Algae in relation to mine water  

Microsoft Academic Search

An annual cycle of bimonthly collections was made from 17 stations located on creeks, rivers, and ponds receiving acid mine drainage in order to obtain information on the species of algae that are tolerant to these waters. Also data were obtained to determine the relative importance of some of the major chemical factors of the water to ecology of the

1969-01-01

152

Alkanes and alkenes in marine benthic algae  

Microsoft Academic Search

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

W. W. Youngblood; M. Blumer

1973-01-01

153

Biosolar production of fuels from algae  

Microsoft Academic Search

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,

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

1976-01-01

154

Sterol chemotaxonomy of marine pelagophyte algae.  

PubMed

Several marine algae of the class Pelagophyceae produce the unusual marine sterol 24-propylidenecholesterol, mainly as the (24E)-isomer. The (24Z)-isomer had previously been considered as a specific biomarker for Aureococcus anophagefferens, the 'brown tide' alga of the Northeast coast of the USA. To test this hypothesis and to generate chemotaxonomic information, the sterol compositions of 42 strains of pelagophyte algae including 17 strains of Aureococcus anophagefferens were determined by GC analysis. A more comprehensive sterol analysis by HPLC and (1)H-NMR was obtained for 17 selected pelagophyte strains. All strains analyzed contained 24-propylidenecholesterol. In all strains belonging to the order Sarcinochrysidales, this sterol was found only as the (E)-isomer, while all strains in the order Pelagomonadales contained the (Z)-isomer, either alone or together with the (E)-isomer. The occurrence of Delta(22) and 24alpha-sterols was limited to the Sarcinochrysidales. The first occurrence of Delta(22)-24-propylcholesterol in an alga, CCMP 1410, was reported. Traces of the rare sterol 26,26-dimethyl-24-methylenecholesterol were detected in Aureococcus anophagefferens, and the (25R)-configuration was proposed, based on biosynthetic considerations. Traces of a novel sterol, 24-propylidenecholesta-5,25-dien-3beta-ol, were detected in several species. PMID:19623555

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

2009-07-01

155

Interactions Between Arsenic Species and Marine Algae.  

National Technical Information Service (NTIS)

The arsenic concentration and speciation of marine algae varies widely, from 0.4 to 23 ng.mg exp -1 , with significant differences in both total arsenic content and arsenic speciation occurring between algal classes. The Phaeophyceae contain more arsenic ...

J. G. Sanders

1978-01-01

156

Biofuels from algae for sustainable development  

Microsoft Academic Search

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

M. Fatih Demirbas

2011-01-01

157

Gametogenesis in the green alga Oedogonium cardiacum  

Microsoft Academic Search

Summary Spermiogenesis in the macandrous, filamentous green algaOedogonium cardiacum is described at the ultrastructural level. The formation of the flagellar apparatus is similar to that in zoosporogenesis. Centrioles, appearingde novo in extranuclear, electron dense material, proliferate into two rows around the nucleus. Rootlet templates concurrently form between adjacent centrioles. The two rows migrate to the side of the cell and

Ronald A. Coss; Jeremy D. Pickett-Heaps

1974-01-01

158

Extracellular Products of Blue Green Algae  

Microsoft Academic Search

SUMMARY An examination was made of soluble extracellular materials produced by Anabaena cylindrica and some other species of blue-green algae, to exasmine whether they have any functional importance. Organisms of all the 15 species (representing 10 genera) examined produced extracellular pigment; with at least 10 of these species part of this pigment was not dif- fusible on dialysis, though the

B. A. WHITTON

1965-01-01

159

Underwater fertilization dynamics of marine green algae  

Microsoft Academic Search

We studied the fertilization dynamics of marine green algae with both analytical methods and numerical simulations. In this study, we focused on a new factor, gametic investment per unit volume of the space in which gametes searched for their partners, and compared the numbers of zygotes formed at lower investments with those at higher investments. As a function of the

Tatsuya Togashi; Paul Alan Cox; John L. Bartelt

2007-01-01

160

Peroxisomal targeting signals in green algae.  

PubMed

Peroxisomal enzymatic proteins contain targeting signals (PTS) to enable their import into peroxisomes. These targeting signals have been identified as PTS1 and PTS2 in mammalian, yeast, and higher plant cells; however, no PTS2-like amino acid sequences have been observed in enzymes from the genome database of Cyanidiochyzon merolae (Bangiophyceae), a primitive red algae. In studies on the evolution of PTS, it is important to know when their sequences came to be the peroxisomal targeting signals for all living organisms. To this end, we identified a number of genes in the genome database of the green algae Chlamydomonas reinhardtii, which contains amino acid sequences similar to those found in plant PTS. In order to determine whether these sequences function as PTS in green algae, we expressed modified green fluorescent proteins (GFP) fused to these putative PTS peptides under the cauliflower mosaic virus 35S promoter. To confirm whether granular structures containing GFP-PTS fusion proteins accumulated in the peroxisomes of Closterium ehrenbergii, we observed these cells after the peroxisomes were stained with 3, 3'-diaminobenzidine. Our results confirm that the GFP-PTS fusion proteins indeed accumulated in the peroxisomes of these green algae. These findings suggest that the peroxisomal transport system for PTS1 and PTS2 is conserved in green algal cells and that our fusion proteins can be used to visualize peroxisomes in live cells. PMID:19214701

Shinozaki, Akiko; Sato, Nagisa; Hayashi, Yasuko

2009-02-12

161

OPTIMAL COST CONTROL STRATEGIES FOR ATTACHED ALGAE  

EPA Science Inventory

This paper presents a cost-benefit analysis for alternative programs intended for the control of the nuisance growth of an attached alga (Cladophora). Such analyses require that changes in water quality be quantitatively related to the cost of implementation for specific manageme...

162

Environmental Requirements of Blue-Green Algae.  

National Technical Information Service (NTIS)

The problem of accelerated eutrophication has many facets, and some are being examined through research to find the keys for solution. The symposium was held to fulfill the need to understand better the environmental requirements of blue-green algae. The ...

1967-01-01

163

Localization and evolution of septins in algae.  

PubMed

Septins are a group of GTP-binding proteins that are multi-functional, with a well-known role in cytokinesis in animals and fungi. Although the functions of septins have been thoroughly studied in opisthokonts (fungi and animals), the function and evolution of plant/algal septins are not as well characterized. Here we describe septin localization and expression in the green algae Nannochloris bacillaris and Marvania geminata. The present data suggest that septins localize at the division site when cytokinesis occurs. In addition, we show that septin homologs may be found only in green algae, but not in other major plant lineages, such as land plants, red algae and glaucophytes. We also found other septin homolog-possessing organisms among the diatoms, Rhizaria and cryptomonad/haptophyte lineages. Our study reveals the potential role of algal septins in cytokinesis and/or cell elongation, and confirms that septin genes appear to have been lost in the Plantae lineage, except in some green algae. PMID:23398289

Yamazaki, Tomokazu; Owari, Satomi; Ota, Shuhei; Sumiya, Nobuko; Yamamoto, Maki; Watanabe, Koichi; Nagumo, Tamotsu; Miyamura, Shinichi; Kawano, Shigeyuki

2013-03-07

164

Spirulina: The Alga That Can End Malnutrition.  

ERIC Educational Resources Information Center

|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)|

Fox, Ripley D.

1985-01-01

165

Changes in chloroplast structure in lichenized algae  

Microsoft Academic Search

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

O. Peksa; P. Skaloud

2008-01-01

166

The taxonomy of blue-green algae  

Microsoft Academic Search

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

B. A. Whitton

1969-01-01

167

Investigation of Drag Reduction by Certain Algae  

Microsoft Academic Search

INVESTIGATIONS were carried out between March and September 1969 to determine the drag reduction effects produced by certain species of algae in No. 3 towing tank at the Ship Division of the National Physical Laboratory. The tank is 48 feet wide, 25 feet deep and 1,300 feet long and contains the water added in August-September 1957. Small additions are regularly

H. R. J. Hawkridge; G. E. Gadd

1971-01-01

168

Bromophenols in Marine Algae and Their Bioactivities  

PubMed Central

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.

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

2011-01-01

169

Simple brominated phenols in red algae  

Microsoft Academic Search

By using TLC and GLC-MS techniques, 23 species of red algae, representing nine orders, were analyzed for the presence of simple bromophenols. Ten bromophenols were detected, five of which might be artefacts. Furthermore, lanosol was identified in sea water from the Polysiphonia Brodiaeizone. Bromophenols were detected in species from the families Ceramiaceae, Delesseriaceae, Bonnemaisoniaceae, Rhodophyllaceae, Corallinaceae and Rhodomelaceae.

Marianne Peders幯; Peter Saenger; L Fries

1974-01-01

170

Spirulina: The Alga That Can End Malnutrition.  

ERIC Educational Resources Information Center

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)

Fox, Ripley D.

1985-01-01

171

Fucoidans sulfated polysaccharides of brown algae  

NASA Astrophysics Data System (ADS)

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

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

2009-08-01

172

Environmental life cycle comparison of algae to other bioenergy feedstocks.  

PubMed

Algae are an attractive source of biomass energy since they do not compete with food crops and have higher energy yields per area than terrestrial crops. In spite of these advantages, algae cultivation has not yet been compared with conventional crops from a life cycle perspective. In this work, the impacts associated with algae production were determined using a stochastic life cycle model and compared with switchgrass, canola, and corn farming. The results indicate that these conventional crops have lower environmental impacts than algae in energy use, greenhouse gas emissions, and water regardless of cultivation location. Only in total land use and eutrophication potential do algae perform favorably. The large environmental footprint of algae cultivation is driven predominantly by upstream impacts, such as the demand for CO(2) and fertilizer. To reduce these impacts, flue gas and, to a greater extent, wastewater could be used to offset most of the environmental burdens associated with algae. To demonstrate the benefits of algae production coupled with wastewater treatment, the model was expanded to include three different municipal wastewater effluents as sources of nitrogen and phosphorus. Each provided a significant reduction in the burdens of algae cultivation, and the use of source-separated urine was found to make algae more environmentally beneficial than the terrestrial crops. PMID:20085253

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

2010-03-01

173

Biofuels from algae: challenges and potential  

PubMed Central

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.

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

2011-01-01

174

Uric acid deposits in symbiotic marine algae.  

PubMed

The symbiosis between cnidarians and dinoflagellate algae is not understood at the cell or molecular level, yet this relationship is responsible for the formation of thousands of square kilometres of coral reefs. We have investigated the nature of crystalline material prominent within marine algal symbionts of Aiptasia sp. anemones. This material, which has historically been considered to be calcium oxalate, is shown to be uric acid. We demonstrate that these abundant uric acid stores can be mobilized rapidly, thereby allowing the algal symbionts to flourish in an otherwise N-poor environment. This is the first report of uric acid accumulation by symbiotic marine algae. These data provide new insight and considerations for understanding the physiological basis of algal symbioses, and represent a new and previously unconsidered aspect of N metabolism in cnidarian, and a variety of other, marine symbioses. PMID:19021889

Clode, Peta L; Saunders, Martin; Maker, Garth; Ludwig, Martha; Atkins, Craig A

2008-11-13

175

Algae columns with anodic stripping voltammetric detection  

SciTech Connect

The use of silica-immobilized algal cells for on-line column separation in conjunction with continuous monitoring of trace metals is described. Algae-silica preparations are highly suitable for flow analysis as they couple the unique reactivity patterns and high binding capacity of algal biomass with the hydrodynamic and mechanical features of porous silica. Such advantages are illustrated by using on-line anodic stripping voltammetry and the alga Chlorella pyrenidosa. Selective and exhaustive removal of interfering constituents circumvents common problems such as overlapping peaks and intermetallic effects. Effects of flow rate, pH, operation time, and other variables are reported. The system is characterized by high durability, simplicity, and economy and offers an attractive alternative to prevalent columns used for flow analysis.

Kubiak, W.W.; Wang, J.; Darnall, D.

1989-03-01

176

Photooxidative Death in Blue-Green Algae  

PubMed Central

When incubated in the light under 100% oxygen, wild-type blue-green algae (Anacystis nidulans, Synechococcus cedrorum) die out rapidly at temperatures of 4 to 15 C, and at 35 C (or at 26 C in the case of S. cedrorum) in the absence of CO2. Photosynthesis is impaired in these cells long before they die. Blocking of photosystem II at high temperatures in the presence of CO2 sensitizes the algae to photooxidative death. Photooxidative death and bleaching of photosynthetic pigments are separable phenomena. Photooxidative conditions were demonstrated in Israeli fish ponds using A. nidulans as the test organism during dense summer blooms, when dissolved CO2 is low, and in winter, when water temperatures generally drop below 15 C. This finding suggests that photooxidative death may be responsible for the sudden decomposition of blue-green blooms in summer, and may be a factor in the absence of blue-green blooms in winter.

Abeliovich, A.; Shilo, M.

1972-01-01

177

Biofuels from algae: challenges and potential.  

PubMed

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

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

2010-09-01

178

Hydrogen production by photosynthetic green algae.  

PubMed

Oxygenic photosynthetic organisms such as cyanobacteria, green algae and diatoms are capable of absorbing light and storing up to 10-13% of its energy into the H-H bond of hydrogen gas. This process, which takes advantage of the photosynthetic apparatus of these organisms to convert sunlight into chemical energy, could conceivably be harnessed for production of significant amounts of energy from a renewable resource, water. The harnessed energy could then be coupled to a fuel cell for electricity generation and recycling of water molecules. In this review, current biochemical understanding of this reaction in green algae, and some of the major challenges facing the development of future commercial algal photobiological systems for H2 production have been discussed. PMID:17133763

Ghirardi, Maria L

2006-08-01

179

Kinetics of nitrate uptake by freshwater algae  

Microsoft Academic Search

The kinetics of nitrate (NO3-) uptake, the maximum uptake velocity (Vm) and the half-saturation constant (Ks), were determined for 18 species of batch-cultured freshwater algae grown without nitrogen limitation. Values of Ks ranged from 0.25 to 6.94 然 l-1Chlorella pyrenoidosa Chick, and Navicula pelliculosa (Breb.) Hilse, respectively. Values of Vm ranged from 0.51 to 5.07 然 l-1 h-1 for Anabaena

Steven G. Halterman; Dale W. Toetz

1984-01-01

180

Fermentation metabolism and its evolution in algae.  

PubMed

Fermentation or anoxic metabolism allows unicellular organisms to colonize environments that become anoxic. Free-living unicellular algae capable of a photoautotrophic lifestyle can also use a range of metabolic circuitry associated with different branches of fermentation metabolism. While algae that perform mixed-acid fermentation are widespread, the use of anaerobic respiration is more typical of eukaryotic heterotrophs. The occurrence of a core set of fermentation pathways among the algae provides insights into the evolutionary origins of these pathways, which were likely derived from a common ancestral eukaryote. Based on genomic, transcriptomic, and biochemical studies, anaerobic energy metabolism has been examined in more detail in Chlamydomonas reinhardtii (Chlamydomonas) than in any other photosynthetic protist. This green alga is metabolically flexible and can sustain energy generation and maintain cellular redox balance under a variety of different environmental conditions. Fermentation metabolism in Chlamydomonas appears to be highly controlled, and the flexible use of the different branches of fermentation metabolism has been demonstrated in studies of various metabolic mutants. Additionally, when Chlamydomonas ferments polysaccharides, it has the ability to eliminate part of the reductant (to sustain glycolysis) through the production of H2, a molecule that can be developed as a source of renewable energy. To date, little is known about the specific role(s) of the different branches of fermentation metabolism, how photosynthetic eukaryotes sense changes in environmental O2 levels, and the mechanisms involved in controlling these responses, at both the transcriptional and post-transcriptional levels. In this review, we focus on fermentation metabolism in Chlamydomonas and other protists, with only a brief discussion of plant fermentation when relevant, since it is thoroughly discussed in other articles in this volume. PMID:23734158

Catalanotti, Claudia; Yang, Wenqiang; Posewitz, Matthew C; Grossman, Arthur R

2013-05-22

181

Algae as reservoirs for coral pathogens.  

PubMed

Benthic algae are associated with coral death in the form of stress and disease. It's been proposed that they release exudates, which facilitate invasion of potentially pathogenic microbes at the coral-algal interface, resulting in coral disease. However, the original source of these pathogens remains unknown. This study examined the ability of benthic algae to act as reservoirs of coral pathogens by characterizing surface associated microbes associated with major Caribbean and Indo-Pacific algal species/types and by comparing them to potential pathogens of two dominant coral diseases: White Syndrome (WS) in the Indo-Pacific and Yellow Band Disease (YBD) in the Caribbean. Coral and algal sampling was conducted simultaneously at the same sites to avoid spatial effects. Potential pathogens were defined as those absent or rare in healthy corals, increasing in abundance in healthy tissues adjacent to a disease lesion, and dominant in disease lesions. Potentially pathogenic bacteria were detected in both WS and YBD and were also present within the majority of algal species/types (54 and 100% for WS and YBD respectively). Pathogenic ciliates were associated only with WS and not YBD lesions and these were also present in 36% of the Indo-Pacific algal species. Although potential pathogens were associated with many algal species, their presence was inconsistent among replicate algal samples and detection rates were relatively low, suggestive of low density and occurrence. At the community level, coral-associated microbes irrespective of the health of their host differed from algal-associated microbes, supporting that algae and corals have distinctive microbial communities associated with their tissue. We conclude that benthic algae are common reservoirs for a variety of different potential coral pathogens. However, algal-associated microbes alone are unlikely to cause coral death. Initial damage or stress to the coral via other competitive mechanisms is most likely a prerequisite to potential transmission of these pathogens. PMID:23936086

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

2013-07-31

182

Fermentation metabolism and its evolution in algae  

PubMed Central

Fermentation or anoxic metabolism allows unicellular organisms to colonize environments that become anoxic. Free-living unicellular algae capable of a photoautotrophic lifestyle can also use a range of metabolic circuitry associated with different branches of fermentation metabolism. While algae that perform mixed-acid fermentation are widespread, the use of anaerobic respiration is more typical of eukaryotic heterotrophs. The occurrence of a core set of fermentation pathways among the algae provides insights into the evolutionary origins of these pathways, which were likely derived from a common ancestral eukaryote. Based on genomic, transcriptomic, and biochemical studies, anaerobic energy metabolism has been examined in more detail in Chlamydomonas reinhardtii (Chlamydomonas) than in any other photosynthetic protist. This green alga is metabolically flexible and can sustain energy generation and maintain cellular redox balance under a variety of different environmental conditions. Fermentation metabolism in Chlamydomonas appears to be highly controlled, and the flexible use of the different branches of fermentation metabolism has been demonstrated in studies of various metabolic mutants. Additionally, when Chlamydomonas ferments polysaccharides, it has the ability to eliminate part of the reductant (to sustain glycolysis) through the production of H2, a molecule that can be developed as a source of renewable energy. To date, little is known about the specific role(s) of the different branches of fermentation metabolism, how photosynthetic eukaryotes sense changes in environmental O2 levels, and the mechanisms involved in controlling these responses, at both the transcriptional and post-transcriptional levels. In this review, we focus on fermentation metabolism in Chlamydomonas and other protists, with only a brief discussion of plant fermentation when relevant, since it is thoroughly discussed in other articles in this volume.

Catalanotti, Claudia; Yang, Wenqiang; Posewitz, Matthew C.; Grossman, Arthur R.

2013-01-01

183

Sustainability assessment of algae cofiring in a coal-fired power plant: A hybrid LCA model  

Microsoft Academic Search

HE environmental performance of various algae cofiring scenarios in a 300 MW coal-fired power plant were investigated using an ecologically based hybrid LCA model. Scenarios included cofiring options utilizing 100% Coal, 75% Coal & 25% Algae, 50% Coal & 50% Algae, 25% Coal & 75% Algae, and 100% Algae. These percentage values represent the share of energy production (MJ) by

M. Kucukvar; O. Tatari

2011-01-01

184

Ecology of the Deep-Water Algae Off La Parguera, Puerto Rico.  

National Technical Information Service (NTIS)

The 157 species of marine algae collected with the help of S.C.U.B.A. and by dredging are distributed among the three major groups of algae; Rhodophyta, (Red Algae), Phaeophyta (Brown algae), Chlorophyta (Green Algae). The Rhodophyta are more numerous tha...

L. R. Almodovar

1969-01-01

185

Eradication of algae in ships' ballast water by electrolyzing  

NASA Astrophysics Data System (ADS)

In order to verify the effectiveness of electrolytic treatment on ships ballast water, experiments are carried out by a pilot system in laboratory. The raw seawater and seawater with different concentrations of different algae are simulated as ships ballast water. The algae in the raw seawater can be killed if it is treated by electrolysis with an initial residual chlorine concentration of 5 mg/L. If the seawater with one kind of algae (Nitzschia closterum, Dicrateria spp., or Pyramidomonnas sp.105cells/mL) is treated by electrolysis with an initial residual chlorine concentration of 5 mg/L, the alga can be sterilized. If the seawater with one kind of algae (Dunaliella sp., Platymonas or Chlorella spp.) is directly treated by electrolyzing with an initial residual chlorine concentration of 4 mg/L, the instant mortality changes with the concentration of different algae. However, after 72 hours, in all treated samples, there are no live algal cells found.

Dang, Kun; Sun, Pei-Ting; Xiao, Jing-Kun; Song, Yong-Xin

2006-12-01

186

Microplate technique for determining accumulation of metals by algae  

SciTech Connect

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.

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

1981-05-01

187

Studies with deoxyribonucleic acid from blue-green algae  

Microsoft Academic Search

The total DNA in species of blue-green algae is similar to that of bacteria on an individual cell, but not on a dry weight, basis. The % G+C content of DNA from four species of blue-green algae has been determined by melting temperature measurement. An attempt tomeasure genetic homology between blue-green algae and certain bacterial species is described.

I. W. Craig; C. K. Leach; N. G. Carr

1969-01-01

188

Bromophenols from marine algae with potential anti-diabetic activities  

NASA Astrophysics Data System (ADS)

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

Lin, Xiukun; Liu, Ming

2012-12-01

189

Zooplankton Feeding on Differentially Labelled Algae and Bacteria  

Microsoft Academic Search

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

Moshe Gophen; Ben Zion Cavari; Thomas Berman

1974-01-01

190

Biosorption of lead and cadmium using marine algae  

Microsoft Academic Search

The use of algae (Ulvafasciata, 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

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

2011-01-01

191

Ecophysiology of algae living in highly acidic environments  

Microsoft Academic Search

Highly acidic environments are inhabited by acidophilic as well as acidotolerant algae. Acidophilic algae are adapted to pH values as low as 0.05 and unable to grow at neutral pH. A prerequisite for thriving at low pH is the reduction of proton influx and an increase in proton pump efficiency. In addition, algae have to cope with a limited supply

Wolfgang Gross

2000-01-01

192

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

193

Respiration in Blue-Green Algae  

PubMed Central

The low rate of endogenous respiration exhibited by the blue-green algae Anacystis nidulans and Phormidium luridum was not increased by the addition of respiratory substrates. However, endogenous respiration was inhibited by low concentrations of cyanide and by high carbon monoxide tensions. In addition, the uncouplers dinitrophenol and carbonyl cyanide p-trifluoromethoxyphenylhydrazone both stimulated the respiratory rate. The transition of cells from the aerobic steady state to anaerobiosis was accompanied by a decrease in the concentration of cellular nicotinamide adenine dinucleotide phosphate (NADP+) and adenosine triphosphate (ATP), whereas the concentration of nicotinamide adenine dinucleotide (NAD+) was unchanged. Concomitant with the metabolite decreases were stoichiometric increases io reduced NADP+ (NADPH), adenosine diphosphate, and adenosine monophosphate. A decrease in ATP was also observed after the addition of uncouplers. These data are interpreted as evidence for the association of oxidative phosphorylation with the oxidation of NADP+-linked substrates in these algae. Membrane fragments isolated from the algal cells oxidized succinate, malate, ferrocytochrome c, ascorbate-tetramethyl-p-phenylenediamine, and reduced 2,6-dichlorophenol indophenol but did not oxidize NADPH or reduced NAD+ in a cyanide-sensitive system. Oxidative phosphorylation has not yet been demonstrated in these fragments, but a dark ATP-Pi exchange, distinct from the lighttriggered exchange associated with photosynthesis, is readily observed. This exchange was inhibited by phloridzin, Atabrine, and uncouplers in concentrations which suggest that the mechanism of oxidative phosphorylation in blue-green algae is different from that found in other bacteria and in mitochondria. These results led to the conclusion that the biochemical basis for obligate autotrophy in these organisms does not lie in the metabolic events associated with terminal electron transport and energy conservation.

Biggins, John

1969-01-01

194

Effect of petroleum hydrocarbons on algae  

SciTech Connect

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

Bhadauria, S. (Raja Balwant Singh College, Agra (India)); Sengar, R.M.S. (Agra College (India)); Mittal, S.; Bhattacharjee, S. (IARI, New Delhi (India))

1992-01-01

195

Biodiesel from algae: challenges and prospects.  

PubMed

Microalgae offer great potential for exploitation, including the production of biodiesel, but the process is still some way from being carbon neutral or commercially viable. Part of the problem is that there is little established background knowledge in the area. We should look both to achieve incremental steps and to increase our fundamental understanding of algae to identify potential paradigm shifts. In doing this, integration of biology and engineering will be essential. In this review we present an overview of a potential algal biofuel pipeline, and focus on recent work that tackles optimization of algal biomass production and the content of fuel molecules within the algal cell. PMID:20399634

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

2010-04-17

196

Screening of different algae for green synthesis of gold nanoparticles  

Microsoft Academic Search

The cyanobacteria Phormidium valderianum, P. tenue and Microcoleus chthonoplastes and the green algae Rhizoclonium fontinale, Ulva intestinalis, Chara zeylanica and Pithophora oedogoniana were exposed to hydrogen tetrachloroaurate solution and were screened for their suitability for producing nano?gold. All three cyanobacteria genera and two of the green algae (Rhizoclonium fontinale and Ulva intestinalis) produced gold nanoparticles intracellularly, confirmed by purple colouration

Dipannita Parial; Hirak K. Patra; Anjan K. R. Dasgupta; Ruma Pal

2012-01-01

197

Catalytic upgrading of biorefinery oil from micro-algae  

Microsoft Academic Search

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

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

2010-01-01

198

Discovery of an endophytic alga in Ginkgo biloba.  

PubMed

Although intracellular associations with mycorrhizal fungi are known for Ginkgo biloba, no other endosymbiotic relationships have ever been reported for this "living fossil." A protoplast culture derived from haploid explants has now revealed the existence of a green alga in vitro, whose eukaryotic status was confirmed by transmission electron microscopic studies. Phylogenetic 18S rDNA sequence analyses showed this alga to be closely related to the lichen photobiont Coccomyxa. Algae, which in host cells exist as more or less undifferentiated "precursor" forms, proliferated within necrosing G. biloba cells of a subculture derived from a zygotic embryo and were finally released into the medium. Light and electron microscopic observations showed that G. biloba cells rapidly filled up with countless green particles whose number increased up to the bursting of the hypertrophic host cells. At the beginning of reproduction no algae were visible in the nutritive medium, demonstrating that the proliferation started inside the G. biloba cells and excluding the possibility of an exogenous contamination. Occasionally, mature algae together with their precursor forms were detected by transmission electron microscopy in intact host cells of a green callus. The algae were easily identified by their similarity to the cultured algae. Eukaryotic algae have never been reported to date to reside inside higher plant cells, whereas several algal associations are well known from the animal kingdom. PMID:21665672

Tr幦ouillaux-Guiller, Jocelyne; Rohr, Thomas; Rohr, Ren; Huss, Volker A R

2002-05-01

199

Sedimentation of algae: relationships with biomass and size distribution1  

Microsoft Academic Search

The influence of the biomass and size distribution of epilimnetic algae on patterns of algal sedimentation was determined in lake enclosures under contrasting conditions of planktivorous fish and nutrient loading (nitrate and phosphate). The addition of fish and nutrients increased the epilimnetic algal biomass, but the addition of nutrients increased the mean length of algae in fish-free enclosures and reduced

Isabelle Larocque; A. Mazumder; M. Proulx; D. R. S. Lean; F. R. Pick

200

Plastid Genomes of Higher Plants and Algae: Structure and Functions  

Microsoft Academic Search

The data on the structure and gene composition in completely sequenced plastid (predominantly chloroplast) genomes of higher plants and algae are reviewed. In higher plants, genome structure and gene composition are highly conserved. Plastid genomes of algae are less conserved and contain several unique genes, which are not found in chloroplast DNAs of higher plants. Plastid genomes encode proteins involved

M. S. Odintsova; N. P. Yurina

2003-01-01

201

ELECTRON MICROSCOPE STUDIES ON BLUE-GREEN ALGAE  

Microsoft Academic Search

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

HANS RIS; R. N. SINGH

1961-01-01

202

On the delineation and higher-level classification of algae  

Microsoft Academic Search

Biological classification has been successively shaped by Neoplatonism, ideas of plenitude and one-dimensional continuity (the Great Chain of Being), two-dimensional continuity (Linnaeus's map), idealized comparative morphology and development and, through phylogenetic theory, Darwinian descent with modification. Concepts of Algae have thus evolved within a succession of very different paradigms. Algae have been imperfect plants; a segment of the Great Chain;

Mark Ragan

1998-01-01

203

Chapter 9 Electrical events in photomovement of green flagellated algae  

Microsoft Academic Search

Phototaxis and photophobic responses in green flagellated algae are mediated by a rhodopsin-type photoreceptor. Its photoexcitation triggers a rapid cascade of electrical phenomena in the cell membrane. The photoinduced electrical responses in green flagellated algae can be recorded extracellularly from an individual cell by a suction pipette technique, or from a cell suspension. Photoexcitation leads to the onset of a

Oleg A. Sineshchekov; Elena G. Govorunova

2001-01-01

204

Phenolic-based Adhesives of Marine Brown Algae  

Microsoft Academic Search

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

Philippe Potin; Catherine Leblanc

205

Biodegradation of an oily bilge waste using algae  

Microsoft Academic Search

A mixed community of microogranisms was collected from the harbor at the North Island Navy Base and was monitored in a test ecosystem containing an oily bilge waste obtained from off-loading ships. Cultures were examined in the presence and absence of the algae. It was thought that the algae might enhance the degradation of the oil waste by providing oxygen

1987-01-01

206

Cryoalgotox: Use of cryopreserved alga in a semistatic microplate test  

SciTech Connect

Use of cryopreserved alga Selenastrum capricornutum has been evaluated as a simple and cost-efficient procedure in a new semistatic algal ecotoxicity test. Experiments have been conducted to compare performance criteria of this method, named Cryoalgotox, versus the classic microplate test using fresh algae. Cryoalgotox 72-h 50% effective concentrations (EC50s) determined with Cd{sup 2+}, Cu{sup 2+}, Cr{sup 6+}, and atrazine were more sensitive, repeatable (low coefficients of variation), and reproducible (low time effect) than the results obtained with the classical microplate tests. The effect of storage time at {minus}80 C on the sensitivity of the algae was assessed using cadmium as a toxic reference; it was shown that algae stored at {minus}80 C over a 3-month period gave comparable toxicity results to those found with fresh algae.

Benhra, A.; Radetski, C.M.; Ferard, J.F. [Univ. de Metz (France). Centre des Sciences de l`Environnement

1997-03-01

207

Comparative Studies on Plastoquinones. IV. Plastoquinones in Algae  

PubMed Central

Plastoquinones A and C have been found in all classes of algae, including representatives of greens, yellow-greens, blue-greens, reds, browns and the flagellate, Euglena. Plastoquinone C from red and brown algae can be separated into 6 different types. An additional plastoquinone C has been found in Gigartina and Rhydomela. From chromatographic evidence this may be equivalent to plastoquinone Co, a C type with a hydroxyl group on the first isoprene unit of the terpenoid sidechain of this substituted benzo-quinone. The ubiquinone, vitamin K and ?-tocopherylquinone content of several algae is also reported. The presence of plastoquinone A in all green plants and many algae indicates that it may be a functional element in photosynthesis. Our study shows that plastoquinone C is more regularly present in algae than has been previously shown.

Sun, Elena; Barr, Rita; Crane, F. L.

1968-01-01

208

[Marine algae of Baja California Sur, Mexico: nutritional value].  

PubMed

The Baja California Peninsula is one of the richest regions of seaweed resources in M憖ico. The objective of this study was to determine the chemical composition of some marine algae species of Baja California Sur, with an economical potential due to their abundance and distribution, and to promote their use as food for human consumption and animal feeding. The algae studied were Green (Ulva spp., Enteromorpha intestinalis, Caulerpa sertularoides, Bryopsis hypnoides), Red (Laurencia johnstonii, Spyridia filamentosa, Hypnea valentiae) and Brown (Sargassum herporizum, S. sinicola, Padina durvillaei, Hydroclathrus clathrathus, Colpomenia sinuosa). The algae were dried and ground before analysis. In general, the results showed that algae had a protein level less than 11%, except L. johnstonii with 18% and low energy content. The ether extract content was lower than 1%. However, the algae were a good source of carbohydrates and inorganic matter. PMID:12868282

Carrillo Dom璯guez, Silvia; Casas Valdez, Margarita; Ramos Ramos, Felipe; P廨ez-Gil, Fernando; S嫕chez Rodr璲uez, Ignacio

2002-12-01

209

Respiratory Chain of Colorless Algae II. Cyanophyta  

PubMed Central

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

Webster, D. A.; Hackett, D. P.

1966-01-01

210

Effects of nitrogen dioxide on algae  

SciTech Connect

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.

Wodzinski, R.S.; Alexander, M.

1980-01-01

211

Effects of nitrogen dioxide on algae  

SciTech Connect

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.

Wodzinski, R.S.; Alexander, M.

1980-01-01

212

Viruses and viruslike particles of eukaryotic algae.  

PubMed Central

Until recently there was little interest or information on viruses and viruslike particles of eukaryotic algae. However, this situation is changing. In the past decade many large double-stranded DNA-containing viruses that infect two culturable, unicellular, eukaryotic green algae have been discovered. These viruses can be produced in large quantities, assayed by plaque formation, and analyzed by standard bacteriophage techniques. The viruses are structurally similar to animal iridoviruses, their genomes are similar to but larger (greater than 300 kbp) than that of poxviruses, and their infection process resembles that of bacteriophages. Some of the viruses have DNAs with low levels of methylated bases, whereas others have DNAs with high concentrations of 5-methylcytosine and N6-methyladenine. Virus-encoded DNA methyltransferases are associated with the methylation and are accompanied by virus-encoded DNA site-specific (restriction) endonucleases. Some of these enzymes have sequence specificities identical to those of known bacterial enzymes, and others have previously unrecognized specificities. A separate rod-shaped RNA-containing algal virus has structural and nucleotide sequence affinities to higher plant viruses. Quite recently, viruses have been associated with rapid changes in marine algal populations. In the next decade we envision the discovery of new algal viruses, clarification of their role in various ecosystems, discovery of commercially useful genes in these viruses, and exploitation of algal virus genetic elements in plant and algal biotechnology. Images

Van Etten, J L; Lane, L C; Meints, R H

1991-01-01

213

The effects of ProAlgaZyme novel algae infusion on metabolic syndrome and markers of cardiovascular health  

Microsoft Academic Search

BACKGROUND: Metabolic Syndrome, or Syndrome X, is characterized by a set of metabolic and lipid imbalances that greatly increases the risk of developing diabetes and cardiovascular disease. The syndrome is highly prevalent in the United States and worldwide, and treatments are in high demand. ProAlgaZyme, a novel and proprietary freshwater algae infusion in purified water, has been the subject of

Julius Oben; Ebangha Enonchong; Dieudonne Kuate; Dora Mbanya; Tiffany C Thomas; DeWall J Hildreth; Thomas D Ingolia; Michael S Tempesta

2007-01-01

214

Chemical characterization of torbanites by transmission micro-FTIR spectroscopy: Origin and extent of compositional heterogeneities  

SciTech Connect

Four Permian to Carboniferous torbanites of various geographical origins were examined by transmission micro-FTIR spectroscopy on doubly polished thin sections (10--25 [mu]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[double bond]O, and aromatic C[double bond]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-catalyzed 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. 69 refs., 9 figs., 4 tabs.

Landais, P.; Rochdi, A. (GDR CNRS-CREGU, Vandoeuvre (France)); Largeau, C.; Derenne, S. (UA CNRS 1381, Paris (France))

1993-06-01

215

Chemical characterization of torbanites by transmission micro-FTIR spectroscopy: Origin and extent of compositional heterogeneities  

NASA Astrophysics Data System (ADS)

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.

Landais, Patrick; Rochdi, A騃ha; Largeau, Claude; Derenne, Sylvie

1993-06-01

216

Studies on R-phycoerythrins from two Antarctic marine red algae and a mesophilic red alga  

Microsoft Academic Search

R-phycoerythrin was purified from two benthic red algae, Iridaea cordata and Phyllophora antarctica, obtained growing at ?2蚓 under thick sea ice off the coast of Antarctica. For the I. cordata protein, the molecular mass was 245,000 Da, and its secondary structure was 60% ? helix, 17% ? sheet, 16% turn, and 7% other.\\u000a The light-harvesting faculties of the I. cordata

Robert MacColl; Leslie E. Eisele; Henry Malak; Richard L. Endres; Edwin C. Williams; Samuel S. Bowser

1999-01-01

217

Isoprenoid biosynthesis in eukaryotic phototrophs: A spotlight on algae  

SciTech Connect

Isoprenoids are one of the largest groups of natural compounds and have a variety of important functions in the primary metabolism of land plants and algae. In recent years, our understanding of the numerous facets of isoprenoid metabolism in land plants has been rapidly increasing, while knowledge on the metabolic network of isoprenoids in algae still lags behind. Here, current views on the biochemistry and genetics of the core isoprenoid metabolism in land plants and in the major algal phyla are compared and some of the most pressing open questions are highlighted. Based on the different evolutionary histories of the various groups of eukaryotic phototrophs, we discuss the distribution and regulation of the mevalonate (MVA) and the methylerythritol phosphate (MEP) pathways in land plants and algae and the potential consequences of the loss of the MVA pathway in groups such as the green algae. For the prenyltransferases, serving as gatekeepers to the various branches of terpenoid biosynthesis in land plants and algae, we explore the minimal inventory necessary for the formation of primary isoprenoids and present a preliminary analysis of their occurrence and phylogeny in algae with primary and secondary plastids. The review concludes with some perspectives on genetic engineering of the isoprenoid metabolism in algae.

Lohr M.; Schwender J.; Polle, J. E. W.

2012-04-01

218

The fauna associated with drift algae captured with a plankton-mesh purse seine net1  

Microsoft Academic Search

A plankton-mesh purse seine used to encircle drift algae in open coastal waters was compared with seines in open water and conventional ichthyoplankton hauls. Densities of small fish and invertebrates were higher in association with drift algae than in open water. Most fish that occurred with drift algae were well pigmented. The fauna of drift algae differed from that of

M. J. Kingsford; J. H. Choat

1985-01-01

219

Photophysiology and cellular composition of sea ice algae  

SciTech Connect

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.

Lizotte, M.P.

1989-01-01

220

Activated chemical defenses suppress herbivory on freshwater red algae.  

PubMed

The rapid life cycles of freshwater algae are hypothesized to suppress selection for chemical defenses against herbivores, but this notion remains untested. Investigations of chemical defenses are rare for freshwater macrophytes and absent for freshwater red algae. We used crayfish to assess the palatability of five freshwater red algae relative to a palatable green alga and a chemically defended aquatic moss. We then assessed the roles of structural, nutritional, and chemical traits in reducing palatability. Both native and non-native crayfish preferred the green alga Cladophora glomerata to four of the five red algae. Batrachospermum helminthosum, Kumanoa holtonii, and Tuomeya americana employed activated chemical defenses that suppressed feeding by 30-60 % following damage to algal tissues. Paralemanea annulata was defended by its cartilaginous structure, while Boldia erythrosiphon was palatable. Activated defenses are thought to reduce ecological costs by expressing potent defenses only when actually needed; thus, activation might be favored in freshwater red algae whose short-lived gametophytes must grow and reproduce rapidly over a brief growing season. The frequency of activated chemical defenses found here (three of five species) is 3-20 higher than for surveys of marine algae or aquatic vascular plants. If typical for freshwater red algae, this suggests that (1) their chemical defenses may go undetected if chemical activation is not considered and (2) herbivory has been an important selective force in the evolution of freshwater Rhodophyta. Investigations of defenses in freshwater rhodophytes contribute to among-system comparisons and provide insights into the generality of plant-herbivore interactions and their evolution. PMID:23011851

Goodman, Keri M; Hay, Mark E

2012-09-26

221

Autophagy in the model alga Chlamydomonas reinhardtii.  

PubMed

Degradation and recycling of intracellular components via autophagy is conserved among eukaryotes. This catabolic process is mediated by autophagy-related (ATG) proteins, which have been identified in different systems including yeasts, mammals and plants. The genome of the model alga Chlamydomonas reinhardtii contains homologues to yeast and plant ATG genes although autophagy has not been previously described in this organism. In our study, we report the molecular characterization of autophagy in Chlamydomonas. Using the ATG8 protein from Chlamydomonas as a molecular autophagy marker, we demonstrate that this degradative process is induced in stationary cells or under different stresses such as nutrient limitation, oxidative stress or the accumulation of misfolded proteins in the endoplasmic reticulum. Our results also indicate that TOR, a major regulator of autophagy, inhibits this process in Chlamydomonas. PMID:20404489

P廨ez-P廨ez, Mar燰 Esther; Crespo, Jos L

2010-05-16

222

Polysaccharide nanofiber made from euglenoid alga.  

PubMed

We have fabricated a polysaccharide nanofiber made from paramylon (?-1,3-glucan), a storage polysaccharide stored as a micrometer-sized particle in the cell of euglenoid alga. Preparation of this nanofiber primarily hinges on the bottom-up approach. First, paramylon, which is originally present in the form of a bundle of nanofibers in a particle, was fibrillated to a randomly coiled polymer by dissolving the particle in a 1.0-mol/L NaOH aqueous solution. Second, the randomly coiled polymer was allowed to self-assemble into a triplex as the NaOH concentration was reduced to 0.25-0.20mol/L. Third, a 20-nm-width nanofiber made from the triplex emerged in the solution when the NaOH concentration was reduced to approximately 0.20mol/L. PMID:23499089

Shibakami, Motonari; Tsubouchi, Gen; Nakamura, Makoto; Hayashi, Masahiro

2012-12-26

223

Interactions of metals and protons with algae  

SciTech Connect

Proton uptake by intact algal cells was found to consist of two processes: (1) a fast (<4 s) surface reaction and (2) a slow (2h) diffusion of protons into cells. A pH titration technique measured only the rapid surface reaction that forms negative sites at higher pH. Adsorption of alkali, alkaline earth, and transition metal ions on algae was quantitatively represented by the Langmuir adsorption isotherm with its two parameters y/sub m/, the maximum amount of metal adsorbed, and K, the equilibrium constant taken as a measure of bond strength. Variations of these parameters with pH and type of metal indicate that metals adsorb to algal surfaces by electrostatic attraction to negative sites, such as carboxylate anions of poly(galaturonic acid) (pectin), as previously suggested.

Crist, R.H.; Oberholser, K.; Schwartz, D.; Marzoff, J.; Ryder, D.; Crist, D.R.

1988-07-01

224

The globins of cyanobacteria and algae.  

PubMed

Approximately, 20 years ago, a haemoglobin gene was identified within the genome of the cyanobacterium Nostoc commune. Haemoglobins have now been confirmed in multiple species of photosynthetic microbes beyond N. commune, and the diversity of these proteins has recently come under increased scrutiny. This chapter summarizes the state of knowledge concerning the phylogeny, physiology and chemistry of globins in cyanobacteria and green algae. Sequence information is by far the best developed and the most rapidly expanding aspect of the field. Structural and ligand-binding properties have been described for just a few proteins. Physiological data are available for even fewer. Although activities such as nitric oxide dioxygenation and oxygen scavenging are strong candidates for cellular function, dedicated studies will be required to complete the story on this intriguing and ancient group of proteins. PMID:24054798

Johnson, Eric A; Lecomte, Juliette T J

2013-01-01

225

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

Microsoft Academic Search

\\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.

Max Teplitski; Sathish Rajamani

226

Properties of phosphatases from green alga Scenedesmus incrassatulus Bahlin and blue-green alga Synechococcus aeruginosus Nag  

Microsoft Academic Search

Studies on phosphatases (acid and alkaline) inSynechococcus aeruginosus, a prokaryotic blue-green alga, andScenedesmus incrassatulus, an eukaryotic green alga under different conditions revealed that the acid phosphatase exhibited maximum activity to pH\\u000a 47 and 37蚓 in both the algae while alkaline phosphatase displayed greatest activity at 375蚓 and 10 pH inSynechococcus aeruginosus and at 106 pH and 375蚓 inScenedesmus incrassatulus. TheK

T R K Reddy; R Lakshminarayana

1988-01-01

227

Studies on moisture relationships of some aquatic and terrestrial algae  

Microsoft Academic Search

SummarySignificant variations among aquatic and terrestrial algae (L. arboricola, Oedogonium sp. and V. hamata), in moisture and hydration percentage have been observed. Both percentages proved to be significantly higher in the aquatic\\u000a forms.

S. Seth

1971-01-01

228

ALGAE AND CRUSTACEANS AS INDICATORS OF BIOACTIVITY OF INDUSTRIAL WASTES  

EPA Science Inventory

Freshwater (Selenastrum capricornutum) and estuarine (Skeketonema costatum) algae were exposed to liquid wastes from 10 industrial sites in laboratory bioassays. All wastes affected algal growth either by stimulation or by stimulation at low concentrations and inhibition at high ...

229

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

PubMed

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

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

2011-05-01

230

ENDOTOXINS, ALGAE AND 'LIMULUS' AMOEBOCYTE LYSATE TEST IN DRINKING WATER  

EPA Science Inventory

Field and laboratory studies were conducted to determine the distribution of algae and bacteria, and investigate sources of endotoxins (lipopolysaccharides) in drinking water. The field survey was performed on five drinking water systems located in Allegheny County, Pennsylvania ...

231

Acid-tolerant and acidophilic algae from Italian environments  

Microsoft Academic Search

The study of the algal flora inhabiting more than 100 sulphuric acid Italian sites is presented. The organisms are divided in acid-tolerant and acidophilic algae on respect to their ecophysiological features. The mechanisms of the acidophily are discussed.

Gabriele Pinto

1993-01-01

232

EXTRACTION OF SUGARS FROM ALGAE FOR DIRECT CONVERSION TO BUTANOL  

EPA Science Inventory

We will have a complete full scale design at the end of this project including algae growth and butanol production. Further, the group will have a working prototype for display at the National Mall. ...

233

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

National Technical Information Service (NTIS)

Biotoxins of freshwater blue-green algae (cyanobacteria) are currently classed as being either hepatotoxic peptides or neurotoxic alkaloids. This study is concerned with the examination of toxins from the species Anabaena flos-aquae, Aphanizomenon flos-aq...

W. W. Carmichael

1985-01-01

234

Colourful Cultures: Classroom Experiments with the Unicellular Alga Haematococcus pluvialis.  

ERIC Educational Resources Information Center

|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)|

Delpech, Roger

2001-01-01

235

Principles of Toxicity Testing with Marine Unicellular Algae.  

National Technical Information Service (NTIS)

Toxicity testing with unicellular algae requires application of the principles of phycology and microbiology to culturing, handling, and exposing the organisms. The brief review describes major aspects of algal toxicity testing, including growth curves, f...

G. E. Walsh

1988-01-01

236

21 CFR 73.275 - Dried algae meal.  

Code of Federal Regulations, 2013 CFR

...broth), molasses, cornsteep liquor, and a maximum of 0.3 percent ethoxyquin. The algae cells are produced by suitable fermentation, under controlled conditions, from a pure culture of the genus Spongiococcum. (b) Uses and restrictions....

2013-04-01

237

Photobiological hydrogen production in green algae and photosynthetic bacteria  

Microsoft Academic Search

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

Greenbaum

1986-01-01

238

Viable Cyanobacteria and Green Algae from the Permafrost Darkness  

Microsoft Academic Search

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

Tatiana A. Vishnivetskaya; Tatiana A

2009-01-01

239

Identification of cytokinin in a green algae extract  

NASA Astrophysics Data System (ADS)

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 chromatographymass 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 cytokininlike substances.

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

1996-06-01

240

Zn嗯 UPTAKE BY BENTHIC MARINE ALGAE  

Microsoft Academic Search

The effects of various environmental factors on Zn嗯 uptake and ; loss were investigated in benthic algae. Increasing the pH promoted Zn嗯 ; uptake and retarded Zn嗯 loss in Ulva lactuca, Porphyra umbilicalis, and ; Laminaria agardi. A similar pH dependency was displayed by killed algae of the ; same species which in all cases absorbed more Zn嗯 than the

Gutknecht

1963-01-01

241

Marine Algae Membrane Phospholipids Study by High Resolution P NMR  

Microsoft Academic Search

Membrane phospholipids were extracted using a modified Folch, Lees and Sloane-Stanley method, from 21 different algae species covering three major divisions of the protista kingdom. In the modified method after chloroform\\/methanol (2:1 v\\/v) extraction and filtration, the solution was backwashed with K-EDTA, 0.6 M, instead of KCl, 1 M. Because algae samples are eavily loaded with cations that broaden NMR

Patricio Meneses; Nelson Navarro

1990-01-01

242

Green algae to land plants: An evolutionary transition  

Microsoft Academic Search

Studies focused upon the evolutionary transition from ancestral green algae to the earliest land plants are important from\\u000a a range of ecological, molecular and evolutionary perspectives. A substantial suite of ultrastructural, biochemical and molecular\\u000a data supports the concept that land plants (embryophytes) are monophyletically derived from an ancestral charophycean alga.\\u000a However, the details of phylogenetic branching patterns linking extant charophytes

Linda E. Graham

1996-01-01

243

Gibberellins in the Red Alga Hypnea musciformis (Wulf.) Lamour  

Microsoft Academic Search

GIBBERELLINS, or substances like gibberellin, have been detected in vascular plants belonging to diverse taxonomic groups1, and there is evidence for their occurrence in a species of green alga2 and two species of brown algae2,3. We report here the presence of gibberellin-like activity in an extract from a species belonging to a further principal group of the plant kingdom, the

R. C. Jennings; A. J. McComb

1967-01-01

244

Photobiological hydrogen production in green algae and photosynthetic bacteria  

SciTech Connect

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 are required.

Greenbaum, E.

1986-01-01

245

Novel anticoagulant compound from fermented red alga Pachymeniopsis elliptica  

Microsoft Academic Search

Natural fermentation was tested as a method of releasing active compounds during screening for potential anticoagulant activity\\u000a in three types of algae (Pachymeniopsis elliptica, Sargassum horneri, and Ulva pertusa). Freeze dried algae samples (2.5g) were fermented by adding 75g of sugar and 500mL of water and thereafter kept at room\\u000a temperature (25蚓) for 3months. Activated partial thromboplastin time (APTT), prothrombin

Prashani Mudika Ekanayake; Chamilani Nikapitiya; Mahanama De Zoysa; Ilson Whang; Se Jae Kim; Jehee Lee

2008-01-01

246

Actin Gene Family Dynamics in Cryptomonads and Red Algae  

Microsoft Academic Search

Here we present evidence for a complex evolutionary history of actin genes in red algae and cryptomonads, a group that acquired\\u000a photosynthesis secondarily through the engulfment of a red algal endosymbiont. Four actin genes were found in the nuclear\\u000a genome of the cryptomonad, Guillardia theta, and in the genome of the red alga, Galdieria sulphuraria, a member of the Cyanidiophytina.

Goro Tanifuji; John M. Archibald

2010-01-01

247

Aragonitic Pennsylvanian phylloid algae from New Mexico: The missing link  

Microsoft Academic Search

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

B. L. Kirkland; C. H. Jr. Moore; J. A. D. Dickson

1991-01-01

248

Screening of hexavalent chromium biosorbent from marine algae  

Microsoft Academic Search

A high-chromate-selective biosorbent with high adsorption capacity was sought by examining the chromate adsorption capacities\\u000a of 48 species of red, brown, or green marine algae sampled from the east coast of Korea. Screening showed a red marine alga\\u000a to have the most excellent adsorption characteristics among them, and it was identified as Pachymeniopsis sp. The period at which Pachymeniopsis sp.

D.-C. Lee; C.-J. Park; J.-E. Yang; Y.-H. Jeong; H.-I. Rhee

2000-01-01

249

Study on algae removal by immobilized biosystem on sponge  

NASA Astrophysics Data System (ADS)

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 lakes 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.

Pei, Haiyan; Hu, Wenrong

2006-10-01

250

Feeding preferences of mesograzers on aquacultured Gracilaria and sympatric algae  

PubMed Central

While large grazers can often be excluded effectively from algal aquaculture operations, smaller herbivores such as small crustaceans and gastropods may be more difficult to control. The susceptibility of three Gracilaria species to herbivores was evaluated in multiple-choice experiments with the amphipod Ampithoe ramondi and the crab Acanthonyx lunulatus. Both mesograzers are common along the Mediterranean coast of Israel. When given a choice, the amphipod preferred to consume Gracilaria lemaneiformis significantly more than either G. conferta or G. cornea. The crab, however, consumed equivalent amounts of G. lemaneiformis and G. conferta, but did not consume G. cornea. Organic content of these algae, an important feeding cue for some mesograzers, could not account for these differences. We further assessed the susceptibility of a candidate species for aquaculture, G. lemaneiformis, against local algae, including common epiphytes. When given a choice of four algae, amphipods preferred the green alga Ulva lactuca over Jania rubens. However, consumption of U. lactuca was equivalent to those of G. lemaneiformis and Padina pavonica. In contrast, the crab showed a marked and significant preference for G. lemaneiformis above any of the other three algae offered. Our results suggest that G. cornea is more resistant to herbivory from common mesograzers and that, contrary to expectations, mixed cultures or epiphyte growth on G. lemaneiformis cannot reduce damage to this commercially appealing alga if small herbivores are capable of recruiting into culture ponds. Mixed cultures may be beneficial when culturing other Gracilaria species.

Cruz-Rivera, Edwin; Friedlander, Michael

2011-01-01

251

Feeding preferences of mesograzers on aquacultured Gracilaria and sympatric algae.  

PubMed

While large grazers can often be excluded effectively from algal aquaculture operations, smaller herbivores such as small crustaceans and gastropods may be more difficult to control. The susceptibility of three Gracilaria species to herbivores was evaluated in multiple-choice experiments with the amphipod Ampithoe ramondi and the crab Acanthonyx lunulatus. Both mesograzers are common along the Mediterranean coast of Israel. When given a choice, the amphipod preferred to consume Gracilaria lemaneiformis significantly more than either G. conferta or G. cornea. The crab, however, consumed equivalent amounts of G. lemaneiformis and G. conferta, but did not consume G. cornea. Organic content of these algae, an important feeding cue for some mesograzers, could not account for these differences. We further assessed the susceptibility of a candidate species for aquaculture, G. lemaneiformis, against local algae, including common epiphytes. When given a choice of four algae, amphipods preferred the green alga Ulva lactuca over Jania rubens. However, consumption of U. lactuca was equivalent to those of G. lemaneiformis and Padina pavonica. In contrast, the crab showed a marked and significant preference for G. lemaneiformis above any of the other three algae offered. Our results suggest that G. cornea is more resistant to herbivory from common mesograzers and that, contrary to expectations, mixed cultures or epiphyte growth on G. lemaneiformis cannot reduce damage to this commercially appealing alga if small herbivores are capable of recruiting into culture ponds. Mixed cultures may be beneficial when culturing other Gracilaria species. PMID:22711945

Cruz-Rivera, Edwin; Friedlander, Michael

2011-12-21

252

Extraction of mercury from ground-water using immobilized algae  

SciTech Connect

Bio-recovery Systems Inc., conducted a project under the Emerging Technology portion of the United States Environmental Protection Agency's (EPAs) Superfund Innovative Technology Evaluation (SITE) Program to evaluate the ability of immobilized algae to absorb mercury from contaminated groundwater in laboratory studies and pilot-scale field tests. Algae biomass was incorporated in a permeable polymeric matrix. The product, AlgaSORB, packed into absorption columns, exhibited excellent flow characteristics, and functioned as a 'biological' ion exchange resin. A sequence of eleven laboratory tests demonstrated the ability of the product to absorb mercury from groundwater that contained high levels of total dissolved solids and hard water components. However, use of a single AlgaSORB preparation yielded non-repeatable results with samples collected at different times of the year. The strategy of extracting the groundwater through two columns containing different times of the year. The strategy of extracting the groundwater through two columns containing different preparations of AlgaSORB was developed and proved successful in laboratory and pilot-scale field tests. Field test results indicate that AlgaSORB could be economically competitive with ion exchange resins for removal of mercury, with the advantage that hardness and other dissolved solids do not appear to compete with heavy metals for binding capacity. (Copyright (c) 1991--Air and Waste Management Association.)

Barkley, N.P.

1991-01-01

253

Radionuclides and trace metals in eastern Mediterranean Sea algae.  

PubMed

Three types of sea alga distributed along the Syrian coast have been collected and analyzed for radioactivity and trace elements. Results have shown that (137)Cs concentrations in all the analyzed sample were relatively low (less than 1.2 Bq kg(-1) dry weight) while the levels of naturally occurring radionuclides, such as (210)Po and (210)Pb, were found to be high in most samples; the highest observed value (27.43 Bq kg(-1) dry weight) for (210)Po being in the red Jania longifurca alga. In addition, most brown alga species were also found to accumulate (210)Po, which indicates their selectivity to this isotope. On the other hand, brown alga (Cystoseira and Sargassum Vulgare) have shown a clear selectivity for some trace metals such as Cr, As, Cu and Co, this selectivity may encourage their use as biomonitor for pollution by trace metals. Moreover, the red alga species were found to contain the highest levels of Mg while the brown alga species were found to concentrate Fe, Mn, Na and K and nonmetals such as Cl, I and Br. PMID:12660047

Al-Masri, M S; Mamish, S; Budier, Y

2003-01-01

254

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

PubMed Central

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.

2011-01-01

255

Phosphorus-Limited Growth of a Green Alga and a Blue-Green Alga  

PubMed Central

The phosphorus-limited growth kinetics of the chlorophyte Scenedesmus quadricauda and the cyanophyte Synechococcus N輍eli were studied by using batch and continuous culturing techniques. The steady-state phosphate transport capability and the phosphorus storage capacity is higher in S. N輍eli than in S. quadricauda. Synechococcus N輍eli 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).

Lang, Douglas S.; Brown, Edward J.

1981-01-01

256

News about cryptochrome photoreceptors in algae  

PubMed Central

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.

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

2013-01-01

257

Coccolithophorid algae culture in closed photobioreactors.  

PubMed

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

Moheimani, Navid R; Isdepsky, Andreas; Lisec, Jan; Raes, Eric; Borowitzka, Michael A

2011-04-25

258

Method and apparatus using an active ionic liquid for algae biofuel harvest and extraction  

DOEpatents

The invention relates to use of an active ionic liquid to dissolve algae cell walls. The ionic liquid is used to, in an energy efficient manner, dissolve and/or lyse an algae cell walls, which releases algae constituents used in the creation of energy, fuel, and/or cosmetic components. The ionic liquids include ionic salts having multiple charge centers, low, very low, and ultra low melting point ionic liquids, and combinations of ionic liquids. An algae treatment system is described, which processes wet algae in a lysing reactor, separates out algae constituent products, and optionally recovers the ionic liquid in an energy efficient manner.

Salvo, Roberto Di; Reich, Alton; Dykes, Jr., H. Waite H.; Teixeira, Rodrigo

2012-11-06

259

Inorganic carbon acquisition by eukaryotic algae: four current questions.  

PubMed

The phylogenetically and morphologically diverse eukaryotic algae are typically oxygenic photolithotrophs. They have a diversity of incompletely understood mechanisms of inorganic carbon acquisition: this article reviews four areas where investigations continue. The first topic is diffusive CO(2) entry. Most eukaryotic algae, like all cyanobacteria, have inorganic carbon concentrating mechanisms (CCMs). The ancestral condition was presumably the absence of a CCM, i.e. diffusive CO(2) entry, as found in a small minority of eukaryotic algae today; however, it is likely that, as is found in several cases, this condition is due to a loss of a CCM. There are a number of algae which are in various respects intermediate between diffusive CO(2) entry and occurrence of a CCM: further study is needed on this aspect. A second topic is the nature of cyanelles and their role in inorganic carbon assimilation. The cyanelles (plastids) of the euglyphid amoeba Paulinella have been acquired relatively recently by endosymbiosis with genetic integration of an ?-cyanobacterium with a Form 1A Rubisco. The ?-carboxysomes in the cyanelles are presumably involved in a CCM, but further investigation is needed.Also called cyanelles are the plastids of glaucocystophycean algae, but is it now clear that these were derived from the ?-cyanobacterial ancestor of all plastids other than that of Paulinella. The resemblances of the central body of the cyanelles of glaucocystophycean algae to carboxysomes may not reflect derivation from cyanobacterial ?-carboxysomes; although it is clear that these algae have CCMs but these are now well characterized. The other two topics concern CCMs in other eukaryotic algae; these CCMs arose polyphyletically and independently of the cyanobacterial CCMs. It is generally believed that eukaryotic algal, like cyanobacterial, CCMs are based on active transport of an inorganic carbon species and/or protons, and they have C(3) biochemistry. This is the case for the organism considered as the third topic, i.e. Chlamydomonas reinhardtii, the eukaryotic alga with the best understood CCM. This CCM involves HCO(3)(-) conversion to CO(2) in the thylakoid lumen so the external inorganic carbon must cross four membranes in series with a final CO(2) effux from the thylakoid. More remains to be investigated about this CCM. The final topic is that of the occurrence of C(4)-like metabolism in the CCMs of marine diatoms. Different conclusions have been reached depending on the organism investigated and the techniques used, and several aspects require further study. PMID:20524069

Raven, John A

2010-06-04

260

Development and characteristics of an adhesion bioassay for ectocarpoid algae.  

PubMed

Species of filamentous brown algae in the family Ectocarpaceae are significant members of fouling communities. However, there are few systematic studies on the influence of surface physico-chemical properties on their adhesion. In the present paper the development of a novel, laboratory-based adhesion bioassay for ectocarpoid algae, at an appropriate scale for the screening of sets of experimental samples in well-replicated and controlled experiments is described. The assays are based on the colonization of surfaces from a starting inoculum consisting of multicellular filaments obtained by blending the cultured alga Ectocarpus crouaniorum. The adhesion strength of the biomass after 14 days growth was assessed by applying a hydrodynamic shear stress. Results from adhesion tests on a set of standard surfaces showed that E. crouaniorum adhered more weakly to the amphiphilic Intersleek 900 than to the more hydrophobic Intersleek 700 and Silastic T2 coatings. Adhesion to hydrophilic glass was also weak. Similar results were obtained for other cultivated species of Ectocarpus but differed from those obtained with the related ectocarpoid species Hincksia secunda. The response of the ectocarpoid algae to the surfaces was also compared to that for the green alga, Ulva. PMID:22146003

Evariste, Emmanuelle; Gachon, Claire M M; Callow, Maureen E; Callow, James A

2012-01-01

261

Sustainability of algae derived biodiesel: a mass balance approach.  

PubMed

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

Pfromm, Peter H; Amanor-Boadu, Vincent; Nelson, Richard

2010-09-21

262

Anti-phytopathogenic activities of macro-algae extracts.  

PubMed

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

Jim幯ez, Edra; Dorta, Fernando; Medina, Cristian; Ram甏ez, Alberto; Ram甏ez, Ingrid; Pe鎙-Cort廥, Hugo

2011-05-03

263

Extraction of mercury from groundwater using immobilized algae  

SciTech Connect

Bio-Recovery Systems, Inc. conducted a project under the Emerging Technology portion of the United States Environmental Protection Agency's (EPAs) Superfund Innovative Technology Evaluation (SITE) Program to evaluate the ability of immobilized algae to adsorb mercury from contaminated groundwater in laboratory studies and pilot-scale field tests. Algal biomass was incorporated in a permeable polymeric matrix. The product, AlgaSORB, packed into adsorption columns, exhibited excellent flow characteristics, and functioned as a biological ion exchange resin. A sequence of eleven laboratory tests demonstrated the ability of this product to adsorb mercury from groundwater that contained high levels of total dissolved solids and hard water components. However, use of a single AlgaSORB preparation yielded nonrepeatable results with samples collected at different times of the year. The strategy of sequentially extracting the groundwater through two columns containing different preparations of AlgaSORB was developed and proved successful in laboratory and pilot-scale field tests. Field test results indicate that AlgaSORB could be economically competitive with ion exchange resins for removal of mercury, with the advantage that hardness and other dissolved solids do not appear to compete with heavy metals for binding capacity.

Barkley, N.P. (Environmental Protection Agency, Cincinnati, OH (United States))

1991-10-01

264

Actin gene family dynamics in cryptomonads and red algae.  

PubMed

Here we present evidence for a complex evolutionary history of actin genes in red algae and cryptomonads, a group that acquired photosynthesis secondarily through the engulfment of a red algal endosymbiont. Four actin genes were found in the nuclear genome of the cryptomonad, Guillardia theta, and in the genome of the red alga, Galdieria sulphuraria, a member of the Cyanidiophytina. Phylogenetic analyses reveal that the both organisms possess two distinct sequence types, designated "type-1" and "type-2." A weak but consistent phylogenetic affinity between the cryptomonad type-2 sequences and the type-2 sequences of G. sulphuraria and red algae belonging to the Rhodophytina was observed. This is consistent with the possibility that the cryptomonad type-2 sequences are derived from the red algal endosymbiont that gave rise to the cryptomonad nucleomorph and plastid. Red algae as a whole possess two very different actin sequence types, with G. sulphuraria being the only organism thus far known to possess both. The common ancestor of Rhodophytina and Cyanidiophytina may have had two actin genes, with differential loss explaining the distribution of these genes in modern-day groups. Our study provides new insight into the evolution and divergence of actin genes in cryptomonads and red algae, and in doing so underscores the challenges associated with heterogeneity in actin sequence evolution and ortholog/paralog detection. PMID:20700735

Tanifuji, Goro; Archibald, John M

2010-08-11

265

Anti-Phytopathogenic Activities of Macro-Algae Extracts  

PubMed Central

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.

Jimenez, Edra; Dorta, Fernando; Medina, Cristian; Ramirez, Alberto; Ramirez, Ingrid; Pena-Cortes, Hugo

2011-01-01

266

Dasycladalean green algae and some problematic algae from the Upper Triassic of the Nayband Formation (northeast Iran)  

NASA Astrophysics Data System (ADS)

This paper describes the dasycladales green algae from two sections of the Rhaetian Howz-e Khan Member of the Nayband Formation, northwest of the Dig-e Rostam motorway service area (south of the type locality of the Formation near the town Naybandan). Both sections are composed of bedded fine-grained limestones containing partly abundant dasycladales algae associated with foraminifers, which are mainly aulotortid types. Additionally scattered samples were collected from several beds of the Howz-e Khan Member in this area. The following dasycladalean taxa are described: Chinianella carpatica (Bystrick), Griphoporella curvata (Gmbel), Griphoporella lutensis nov. sp., some undetermined dasycladacean taxa, problematic algae like Lithocodium aggregatum Elliott, Bacinella irregularis Radoicic, and Thaumatoporella parvovesiculifera (Raineri). While Chinianella carpatica is not numerous and the other described algae are rare, Griphoporella curvata is extremely abundant in the investigated material. This paper describes Ch. carpatica for the first time from the Triassic of Iran and also includes a discussion of the strong variability of G. curvata. Additionally we include an informal description of a problematic fossil (animal: shell fragment?; plant: alga?).

Senowbari-Daryan, Baba; Rashidi, Koorosh; Saberzadeh, Behnam

2011-12-01

267

[Nutritive value of the spirulina algae (Spirulina maxima)].  

PubMed

Nine experiments were conducted, five of them in vivo to determine the limiting amino acids and digestibility of spiruline algae for the rat, and four in vitro to determine the digestibility of the product in pepsin and ruminal liquid. None of the amino acids studied (lysine, methionine, histidine) added alone or in combination to 10% protein (either crude or true) diets provided exclusively by spiruline, seems to be limiting although the results could be masked by the low palatability and acceptability of the product by the rats. The apparent digestibility of the algae was 67.4%. For the in vitro tests, the algae were subjected to several physical or chemical treatments, and the digestibility of the resulting product determined by four different techniques. In no case did the tested treatments have any effect on its digestibility. PMID:753178

Tejada de Hern嫕dez, I; Shimada, A S

1978-06-01

268

Seasonal changes of ?-tocopherol in green marine algae (Caulerpa genus).  

PubMed

Marine algae are a promising source of beneficial compounds for human use. Among these, pro-vitamin A carotenoids and vitamins B, C, and E stand out. The objective of this study was to investigate seasonal variation of ?-tocopherol levels in 5 species of green marine algae of the Caulerpa genus. This research was carried out with both fresh and dry specimens; and, in addition, differences arising as a result of the drying process were examined. Analyses were carried out by high-performance liquid chromatography (HPLC) using an isocratic system and a reversed-phase C-18 column. The distribution of ?-tocopherol throughout the year in?Caulerpa?genus was variable. All samples of both fresh and dried algae contained ?-tocopherol, except for the dried?C. racemosa?from March 2006. The drying process was responsible for losses of ?-tocopherol ranging from 21% to 93%. PMID:22417426

Pires-Cavalcante, Kelma Maria Dos Santos; de Alencar, Daniel Barroso; de Sousa, M嫫cia Barbosa; Sampaio, Alexandre Holanda; Saker-Sampaio, Silvana

2011-04-27

269

A look at diacylglycerol acyltransferases (DGATs) in algae.  

PubMed

Triacylglycerols (TAGs) from algae are considered to be a potentially viable source of biodiesel and thereby renewable energy, but at the moment very little is known about the biosynthetic pathway in these organisms. Here we compare what is currently known in eukaryotic algal species, in particular the characteristics of algal diacylglycerol acyltransferase (DGAT), the last enzyme of de novo TAG biosynthesis. Several studies in plants and mammals have shown that there are two DGAT isoforms, DGAT1 and DGAT2, which catalyse the same reaction but have no clear sequence similarities. Instead, they have differences in functionality and spatial and temporal expression patterns. Bioinformatic searches of sequenced algal genomes reveal that most algae have multiple copies of putative DGAT2s, whereas other eukaryotes have single genes. Investigating whether these putative isoforms are indeed functional and whether they confer significantly different phenotypes to algal cells will be vital for future efforts to genetically modify algae for biofuel production. PMID:22750092

Chen, Jit Ern; Smith, Alison G

2012-06-29

270

Algae from the arid southwestern United States: an annotated bibliography  

SciTech Connect

Desert algae are attractive biomass producers for capturing solar energy through photosynthesis of organic matter. They are probably capable of higher yields and efficiencies of light utilization than higher plants, and are already adapted to extremes of sunlight intensity, salinity and temperature such as are found in the desert. This report consists of an annotated bibliography of the literature on algae from the arid southwestern United States. It was prepared in anticipation of efforts to isolate desert algae and study their yields in the laboratory. These steps are necessary prior to setting up outdoor algal culture ponds. Desert areas are attractive for such applications because land, sunlight, and, to some extent, water resources are abundant there. References are sorted by state.

Thomas, W.H.; Gaines, S.R.

1983-06-01

271

[Effectiveness and characteristics of treating algae-laden raw water by stocking silver carp].  

PubMed

To reduce the negative effect of algae on conventional water treatment, a full-scale research of removing algae from algae-laden raw water by stocking filter-feeding silver carp was processed. After the pretreatment in a presedimentation tank with silver carp, the concentration of phytoplankton, the biomass of cyanobacteria and Microsystis flos-aquae in algae-laden raw water with Microsystis flos-aquae its dominant species decreased 61.8%, 76.1% and 78.2% respectively. This effective decrease of algae load on conventional process created favorable conditions for water treatment. Analysis indicates that food habit of silver carp and algae size are two causes of different removal efficiency between cyanobacteria and green algae. The results show that biomanipulation of silver carp is applicable for treating algae-laden raw water in which colonial cyanobacteria is dominant. PMID:18649519

Fan, Zhen-Qiang; Cui, Fu-Yi; Ma, Hua; He, Wen-Jie; Yin, Pei-Jun

2008-03-01

272

Aragonitic Pennsylvanian phylloid algae from New Mexico: The missing link  

SciTech Connect

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.

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

273

Real-Time Red Tide Algae Classification Using Naive Bayes Classifier and SVM  

Microsoft Academic Search

This paper presents a real-time alga classifier designed for flow-cytometry-based marine alga monitoring systems. The difficulties of such classification includes: (1) the shape of the same algae category is deformable, and largely variant due to the individual differences and mature stage; (2) the image of algae may vary due to different 3D positions to the imaging plane and partial occlusion;

Jiang Tao; Wang Cheng; Wang Boliang; Xie Jiezhen; Jiao Nianzhi; Luo Tingwei

2008-01-01

274

Effectiveness and mechanism of potassium ferrate(VI) preoxidation for algae removal by coagulation  

Microsoft Academic Search

Jar tests were conducted to evaluate the effectiveness of potassium ferrate preoxidation on algae removal by coagulation. Laboratory studies demonstrated that pretreatment with potassium ferrate obviously enhanced the algae removal by coagulation with alum [Al2(SO4)318H2O]. Algae removal efficiency increased remarkably when the water was pretreated with ferrate. A very short time of preoxidation was enough to achieve substantial algae removal

Jun Ma; Wei Liu

2002-01-01

275

Algae as promising organisms for environment and health.  

PubMed

Algae, like other plants, produce a variety of remarkable compounds collectively referred to as secondary metabolites. They are synthesized by these organisms at the end of the growth phase and/or due to metabolic alterations induced by environmental stress conditions. Carotenoids, phenolic compounds, phycobiliprotein pigments, polysaccharides and unsaturated fatty acids are same of the algal natural products, which were reported to have variable biological activities, including antioxidant activity, anticancer activity, antimicroabial activity against bacteria-virus-algae-fungi, organic fertilizer and bioremediation potentials. PMID:21862867

Shalaby, Emad A

2011-09-01

276

Antimicrobial effect of phlorotannins from marine brown algae.  

PubMed

Marine organisms exhibit a rich chemical content that possess unique structural features as compared to terrestrial metabolites. Among marine resources, marine algae are a rich source of chemically diverse compounds with the possibility of their potential use as a novel class of artificial food ingredients and antimicrobial agents. The objective of this brief review is to identify new candidate drugs for antimicrobial activity against food-borne pathogenic bacteria. Bioactive compounds derived from brown algae are discussed, namely phlorotannins, that have anti-microbial effects and therefore may be useful to explore as potential antimicrobial agents for the food and pharmaceutical industries. PMID:22735502

Eom, Sung-Hwan; Kim, Young-Mog; Kim, Se-Kwon

2012-06-23

277

Evidence that an Amoeba Acquired a Chloroplast by Retaining Part of an Engulfed Eukaryotic Alga  

Microsoft Academic Search

Chlorarachniophytes are amoeboid algae with unusual chloroplasts. Instead of the usual two membranes that surround the chloroplasts of plants, green algae, and red algae, the chloroplasts of chlorarachniophytes have four bounding membranes. The extra membranes may reflect an unusual origin of chlorarachniophyte chloroplasts. Rather than inheriting the organelle directly from their ancestors, chlorarachniophytes may have adopted the chloroplast of an

Geoffrey I. McFadden; Paul R. Gilson; Claudia J. B. Hofmann; Gregory J. Adcock; Uwe-G. Maier

1994-01-01

278

Importance of algae in the diet of the oligochaetes Lumbriculus variegatus (M釿ler) and Rhyacodrilus sodalis (Eisen)  

Microsoft Academic Search

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 7085% of the gut contents of both species. The most frequently ingested algae were Cymatopleura elliptica, Cymbella spp., Epithemia turgida, Pinnularia spp., and Synedra ulna.

James W. Moore

1978-01-01

279

The chloroplast pigments of some green and yellow-green algae  

Microsoft Academic Search

Pigment analysis carried out by thin-layer chromatography confirms that Chlorocloster engadinensis Vischer, C. solani George and Nephrodiella brevis Vischer are all green algae (Chlorophyceae) and not yellow-green algae (Xanthophyceae) as has been suggested. The pigments of Coccomyxa elongata Jaag, C. simplex (Pringsheim) Mainx and Pyrobotrys stellata Korshikov are also typical of green algae. The pigments of Pleurochloris commutata Pascher, P.

S. J. Whittle; P. J. Casselton

1969-01-01

280

Ecophysiological performance of an urban strain of the aeroterrestrial green alga Klebsormidium sp. (Klebsormidiales, Klebsormidiophyceae)  

Microsoft Academic Search

Aeroterrestrial green algae are among the most ubiquitous members of the microbial flora colonizing aerial surfaces. Filamentous green algae, in particular, produce large populations in several natural and artificial habitats. In recent years it has been shown that the bases of the walls of urban environments are frequently colonized by filamentous green algae. However, information concerning the physiology of these

Ulf Karsten; Fabio Rindi

2010-01-01

281

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

Microsoft Academic Search

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

Gholamhassan Najafi; Barat Ghobadian; Talal F. Yusaf

2011-01-01

282

Use of red algae as hosts by kelp-associated amphipods  

Microsoft Academic Search

To what extent densities of amphipods associated with red algae are related to food value or habitat form and architecture were investigated. Four epiphytic red algae common on kelp stipes ( Laminaria hyperborea) were sampled, and the densities of three species of associated amphipods were analysed. The algae were chosen to represent different structures and levels of architectural complexity. Palmaria

K. M. Norderhaug

2004-01-01

283

GROSS BETA RADIOACTIVITY OF THE ALGAE AT ENIWETOK ATOLL, 1954-1956  

Microsoft Academic Search

A study was made to determine the amounts of radioactivity in marine ; algae, water, and lagoon bottom sand collected at Eniwetok Atoll during the ; period April 1954 to April 1956. The highest levels of beta radioactivity of ; algae collected after the detonation of a nuclear device (Nectar) were in algae ; from those islands closest to the

Palumbo

1959-01-01

284

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 ...

285

Heparinoid-active sulphated polysaccharides from marine algae as potential blood anticoagulant agents  

Microsoft Academic Search

Anticoagulant properties of marine algae have been extensively studied for the last 60 years. Su lphated polysaccharides (SPS) of three major divisions of marine algae, viz. Rhodophyta, Phaeophyta and Chlorophyta are reported to have such properties. Some of the active components have been chemically well characterized. Sulphated galactans and fuc- oidan sulphates from red and brown algae, respec- tively, and

M. Shanmugam; K. H. Mody

286

Coprecipitation of phosphate with calcite in the presence of photosynthesizing green algae  

Microsoft Academic Search

The results of phosphate coprecipitation on calcite, occurring in a solution of calcium bicarbonate, in the presence of photosynthesizing algae are presented. The precipitation experiments were carried out at 20蚓 in an illuminated culture apparatus with continuous recordings of pH and conductivity. The alga used in the experiment was the unicellular green alga Chlorococcum sp. The results are analysed using

A. M. Hartley; W. A. House; M. E. Callow; B. S. C. Leadbeater

1997-01-01

287

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

Microsoft Academic Search

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

K. Roberts

1974-01-01

288

Antioxidant properties of a new antioxidative peptide from algae protein waste hydrolysate in different oxidation systems  

Microsoft Academic Search

Microalgae have been a popular edible food, but there are no known reports on the antioxidative peptides derived from microalgae. The algae protein waste, which is normally discarded as animal feed, is a by-product during production of algae essence from microalgae, Chlorella vulgaris. Algae protein waste was hydrolyzed using pepsin, and a potent antioxidative peptide of VECYGPNRPQF was separated and

I.-Chuan Sheih; Tung-Kung Wu; Tony J. Fang

2009-01-01

289

CHANGES IN STRUTURE OF THE MARINE ALGAE SARGASSUM sp. DURING DRYING  

Microsoft Academic Search

Biological structures such as bacteria, fungi, algae and others of higher structural complexity are potential adsorbents due to their abundant presence in the environment. Biosorbents derived from the biomass of marine algae have shown high uptake capacity for heavy metals. Drying of the biosorbent is a stage preceding the adsorption\\/dessorption cycle. In the case of the algae, drying of the

J. A. Cavalcante; M. Luzio

290

Where Have All the Algae Gone, or, How Many Kingdoms Are There?  

ERIC Educational Resources Information Center

|Examined 10 introductory college-level, general biology survey textbooks for the coverage of algae to assess the efficacy of coverage. Describes a proposal of seven kingdoms and discusses the disposition of algae among five of these kingdoms. Contends that textbooks should highlight the concept of algae across the five kingdoms. Contains 59

Blackwell, Will H.; Powell, Martha J.

1995-01-01

291

Critical conditions for ferric chloride-induced flocculation of freshwater algae.  

PubMed

The effects of algae concentration, ferric chloride dose, and pH on the flocculation efficiency of the freshwater algae Chlorella zofingiensis can be understood by considering the nature of the electrostatic charges on the algae and precipitate surfaces. Two critical conditions are identified which, when met, result in flocculation efficiencies in excess of 90% for freshwater algae. First, a minimum concentration of ferric chloride is required to overcome the electrostatic stabilization of the algae and promote bridging of algae cells by hydroxide precipitates. At low algae concentrations, the minimum amount of ferric chloride required increases linearly with algae concentration, characteristic of flocculation primarily through electrostatic bridging by hydroxide precipitates. At higher algae concentrations, the minimum required concentration of ferric chloride for flocculation is independent of algae concentration, suggesting a change in the primary flocculation mechanism from bridging to sweep flocculation. Second, the algae must have a negative surface charge. Experiments and surface complexation modeling show that the surface charge of C. zofingiensis is negative above a pH of 4.0 0.3 which agrees well with the minimum pH required for effective flocculation. These critical flocculation criteria can be extended to other freshwater algae to design effective flocculation systems. PMID:21882173

Wyatt, Nicholas B; Gloe, Lindsey M; Brady, Patrick V; Hewson, John C; Grillet, Anne M; Hankins, Matthew G; Pohl, Phillip I

2011-09-09

292

Short-term uptake of heavy metals by periphyton algae  

Microsoft Academic Search

The utilization of periphyton activity for the removal of heavy metals from enriched small streams has been examined. By means of short-term batch laboratory experiments the courses of metal uptake have been studied. For uptake study naturally growing periphyton community and periphytic filamentous algae Cladophora glomerata and Oedogonium rivulare have been used. Uptakes of nine heavy metals Pb, Cd,

Jan Vymazal

1984-01-01

293

CHEMICAL COMPOSITION OF THE WALLS OF CERTAIN ALGAE  

Microsoft Academic Search

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

MARY E. WURDACK

294

Evaluation of algae based feed in Goldfish ( Carassius auratus ) nutrition  

Microsoft Academic Search

A short term laboratory feeding trial was conducted to evaluate the importance of algae based value added feed for the popular\\u000a ornamental fish Carassius auratus (Gold fish). The feed was tested against Daphnia the conventional feed used for Goldfish. Fresh algal biomass of Nostoc ellipsosporum and Navicula minima were mixed with daphnia to formulate the value added feed and

Nilofer Khatoon; Protyusha Sengupta; Sumit Homechaudhuri; Ruma Pal

2010-01-01

295

Differential sensitivity of green algae to allelopathic substances from Chara  

Microsoft Academic Search

Three short-term laboratory experiments were conducted to investigate allelopathic effects of a mixture of Chara globularis var. globularis Thuillier and Chara contraria var. contraria A. Braun ex Ktzing on three different green algae. Single phytoplankton species were exposed to filtered water originating from charophyte cultures. Phytoplankton growth was monitored by determination of chlorophyll concentrations in batch cultures. The change in

G. Mulderij; E. Van Donk; J. G. M. Roelofs

2003-01-01

296

The role of algae in mine drainage bioremediation  

Microsoft Academic Search

The effect of mine drainage effluent on aquatic ecosystems has been abundantly documented and remediation efforts to data have always been costly and temporary at best. Bioremediation, using natural environmental microbes, to treat acid mine drainage has shown great promise as an affordable, permanent treatment. At Lambda, we used mixatrophic cultures of bacteria, algae, protozoans and fungal groups on four

Davison

1990-01-01

297

Algae biodiesel has potential despite inconclusive results to date.  

PubMed

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

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

2011-11-03

298

Antibiotic activity of lectins from marine algae against marine vibrios.  

PubMed

Saline and aqueous ethanol extracts of marine algae and the lectins from two red algal species were assayed for their antibiotic activity against marine vibrios. Experimental studies were also carried out on the influence of environmental factors on such activity, using batch cultures. The results indicated that many of the saline extracts of the algal species were active and that the activity was selective against those vibrios assayed. The algal extracts were active against Vibrio pelagius and the fish pathogen V. vulnificus, but inactive against V. neresis. Algal lectins from Eucheuma serra (ESA) and Galaxaura marginata (GMA) strongly inhibited V. vulnificus but were inactive against the other two vibrios. The antibacterial activity of algal extracts was inhibited by pretreatment with various sugars and glycoprotein. Extracts of the two red algae, E. serra and Pterocladia capillacea, in saline and aqueous ethanol, inhibited markedly the growth rate of V. vulnificus at very low concentrations. Culture results indicated that metabolites active against V. vulnificus were invariably produced in P. capillacea over a wide range of temperature, light intensity, and nutritional conditions. Enhanced antibacterial activity occurred when P. capillacea was grown under higher irradiance, severe nutrient stress and moderate temperature (20 degrees C), reflecting the specific antibiotic characteristics of this alga. The strong antibiotic activity of lectins towards fish pathogenic bacteria reveals one of the important roles played by algal lectins, as well as the potential high economic value of those marine algae assayed for aquaculture and for biomedical purposes. PMID:12884128

Liao, W-R; Lin, J-Y; Shieh, W-Y; Jeng, W-L; Huang, R

2003-07-23

299

Intracellular invasion of green algae in a salamander host  

PubMed Central

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 2644 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 cellcell recognition, possible exchange of metabolites or DNA, and potential congruence between host and symbiont population structures.

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

2011-01-01

300

Biodegradation of phenols by the alga Ochromonas danica.  

PubMed Central

The eukaryotic alga Ochromonas danica, a nutritionally versatile, mixotrophic chrysophyte, grew on phenol as the sole carbon source in axenic culture and removed the phenol carbon from the growth medium. Respirometric studies confirmed that the enzymes involved in phenol catabolism were inducible and that the alga oxidized phenol; the amount of oxygen consumed per mole of oxidized substrate was approximately 65% of the theoretical value. [U-14C]phenol was completely mineralized, with 65% of the 14C label appearing as 14CO2, approximately 15% remaining in the aqueous medium, and the rest accounted for in the biomass. Analysis of the biomass showed that 14C label had been incorporated into the protein, nucleic acid, and lipid fractions; phenol carbon is thus unequivocally assimilated by the alga. Phenol-grown cultures of O. danica converted phenols to the corresponding catechols, which were further metabolized by the meta-cleavage pathway. This surprising result was rigorously confirmed by taking the working stock culture through a variety of procedures to check that it was axenic and repeating the experiments with algal extracts. This is, as far as is known, the first definitive identification of the meta-cleavage pathway for aromatic ring degradation in a eukaryotic alga, though its incidence in other eukaryotes has been (infrequently) suggested.

Semple, K T; Cain, R B

1996-01-01

301

Biodiesel Fuel Production from Algae as Renewable Energy  

Microsoft Academic Search

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

Sharif Hossain; Aishah Salleh

302

Bioactive natural products from blue-green algae  

Microsoft Academic Search

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.

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

1994-01-01

303

Bioactive phloroglucinols from the brown alga Zonaria diesingiana  

Microsoft Academic Search

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

Puntip Wisespongpand; Masayuki Kuniyoshi

2003-01-01

304

Evaluation of Techniques for Algae Removal from Wastewater Stabilization Ponds.  

National Technical Information Service (NTIS)

The removal of algae from stabilization pond effluent can be accomplished by many methods, and under certain conditions each process can be shown to be economical and operational. A discussion of the most promising procedures proposed as a means of polish...

D. B. Porcella E. J. Middlebrooks G. R. Marshall J. H. Reynolds R. A. Gearheart

1974-01-01

305

Lysis of Blue-Green Algae by Myxobacter  

PubMed Central

Enrichment from local fishponds led to the isolation of a bacterium capable of lysing many species of unicellular and filamentous blue-green algae, as well as certain bacteria. The isolate is an aflagellate, motile rod which moves in a gliding, flexuous manner; the organism is capable of digesting starch and agar, but not cellulose and gelatin. Its deoxyribonucleic acid base pair composition (per cent guanine plus cytosine ?70) shows a close resemblance to that of the fruiting myxobacteria. Algae in lawns on agar plates were lysed rapidly by the myxobacter, but only limited and slow lysis occurred in liquid media, and no lysis took place when liquid cultures were shaken. No diffusible lytic factors would be demonstrated. Continuous observation of the lytic process under a phase-contrast microscope suggested that a close contact between the polar tip of the myxobacter and the alga is necessary for lysis. The lytic action is limited to the vegetative cells of the algae, whereas heterocysts are not affected. The gas vacuoles of the algal host are the only remnant visible after completion of digestion by the myxobacter. Images

Shilo, Miriam

1970-01-01

306

Decreased abundance of crustose coralline algae due to ocean acidification  

NASA Astrophysics Data System (ADS)

Owing to anthropogenic emissions, atmospheric concentrations of carbon dioxide could almost double between 2006 and 2100 according to business-as-usual carbon dioxide emission scenarios. Because the ocean absorbs carbon dioxide from the atmosphere, increasing atmospheric carbon dioxide concentrations will lead to increasing dissolved inorganic carbon and carbon dioxide in surface ocean waters, and hence acidification and lower carbonate saturation states. As a consequence, it has been suggested that marine calcifying organisms, for example corals, coralline algae, molluscs and foraminifera, will have difficulties producing their skeletons and shells at current rates, with potentially severe implications for marine ecosystems, including coral reefs. Here we report a seven-week experiment exploring the effects of ocean acidification on crustose coralline algae, a cosmopolitan group of calcifying algae that is ecologically important in most shallow-water habitats. Six outdoor mesocosms were continuously supplied with sea water from the adjacent reef and manipulated to simulate conditions of either ambient or elevated seawater carbon dioxide concentrations. The recruitment rate and growth of crustose coralline algae were severely inhibited in the elevated carbon dioxide mesocosms. Our findings suggest that ocean acidification due to human activities could cause significant change to benthic community structure in shallow-warm-water carbonate ecosystems.

Kuffner, Ilsa B.; Andersson, Andreas J.; Jokiel, Paul L.; Rodgers, Ku`Ulei S.; MacKenzie, Fred T.

2008-02-01

307

The Photoreceptor Current of the Green Alga Chlamydomonas  

Microsoft Academic Search

The unicellular alga Chlamydomonas possesses a visual system which guides it to places that are optimal for photosynthetic growth. The rhodopsin, serving as the photoreceptor, conveys light information into a cellular signal. This signal is transmitted via several electrical steps to the flagella, where it modulates the flagellar beating pattern. The first detectable electrical process is the photoreceptor current, which

Hartmann Harz; Christina Nonnengasser; Peter Hegemann

1992-01-01

308

Life history characteristics of Brachionus plicatilis (rotifera) fed different algae  

Microsoft Academic Search

A detailed study of the life history of the rotifer Brachionus plicatilis was done at 20 蚓, 20 ppt salinity, and 90 mg C 1-1 food concentration. Rotifers were grown individually in culture plate wells (150 痞 culture volume) and fed Isochrysis galbana Tahiti, Tetraselmis sp., Nannochloris atomus, or a l : 1 mixture (weight) of two of the algae.

J. Korstad; Y. Olsen; O. Vadstein

1989-01-01

309

Interactions between algae and the microbial loop in experimental microcosms  

Microsoft Academic Search

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

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

2001-01-01

310

Mechanism of Calcification in the Marine Alga Emiliania huxleyi  

Microsoft Academic Search

Coccoliths are delicate calcified structures produced by marine unicellular algae. In the species Emiliania huxleyi the calcium carbonate (mostly calcite) is closely associated with a complex, acidic polysaccharide which binds calcium ions specifically, interferes with the in vitro crystallization of calcium carbonate, and appears to be bound to a positively charged protein before the crystallization process is finished. Ultra-high resolution

P. Westbroek; E. W. de Jong; P. van der Wal; A. H. Borman; J. P. M. de Vrind; D. Kok; W. C. de Bruijn; S. B. Parker

1984-01-01

311

Basis for the resistance of several algae to microbial decomposition.  

PubMed

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 was 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

Gunnison, D; Alexander, M

1975-06-01

312

Antibiotic activity of lectins from marine algae against marine vibrios  

Microsoft Academic Search

Saline and aqueous ethanol extracts of marine algae and the lectins from two red algal species were assayed for their antibiotic activity against marine vibrios. Experimental studies were also carried out on the influence of environmental factors on such activity, using batch cultures. The results indicated that many of the saline extracts of the algal species were active and that

W.-R. Liao; J.-Y. Lin; W.-Y. Shieh; W.-L. Jeng; R. Huang

2003-01-01

313

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

Microsoft Academic Search

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. TEYSSDRE'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 \\

Bernard TEYSSDRE

2006-01-01

314

Extracellular fibril production by freshwater algae and cyanobacteria  

Microsoft Academic Search

In order to study the ability of freshwater algae and cyanobacteria to form extracellular fibrils, a screening test using ruthenium red (RR) staining was carried out on 28 species. Five of these were examined for growth and production of fibrillar material in culture media of different phosphate (P;) contents. RR-staining and uronic acid determinations at various stages of algal growth

Tatiana Strycek; Judy Acreman; Alison Kerry; Gary G. Leppard; Milan V. Nermut; Donn J. Kushner

1992-01-01

315

Metabolism of glucose by unicellular blue-green algae  

Microsoft Academic Search

A facultative photo- and chemoheterotroph, the unicellular bluegreen alga Aphanocapsa 6714, dissimilates glucose with formation of CO2 as the only major product. A substantial fraction of the glucose consumed is assimilated and stored as polyglucose (probably glycogen). The oxidation of glucose proceeds through the pentose phosphate pathway. The first enzyme of this pathway, glucose-6-phosphate dehydrogenase, is partly inducible. In addition,

R. A. Pelroy; R. Rippka; R. Y. Stanier

1972-01-01

316

Assessment of the toxicity to algae of colored substances  

Microsoft Academic Search

An assessment of the toxicity of substances to aquatic organisms is needed for European Classification and Risk Assessment purposes (EEC 1993a, 1993b). This involves measuring the acute toxicity of the substance to fish, Daphnia magna and algae~ The assessment uses the acute data obtained to extrapolate to chronic effects, and so should not take into account gross physical effects. In

M. H. I. Comber; D. V. Smyth; R. S. Thompson

1995-01-01

317

Marine blue-green algae have a unique osmoregulatory system  

Microsoft Academic Search

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.

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

1983-01-01

318

Grazing-activated chemical defence in a unicellular marine alga  

Microsoft Academic Search

Marine plankton use a variety of defences against predators, some of which affect trophic structure and biogeochemistry. We have previously shown that, during grazing by the protozoan Oxyrrhis marina on the alga Emiliania huxleyi, dimethylsulphoniopropionate (DMSP) from the prey is converted to dimethyl sulphide (DMS) when lysis of ingested prey cells initiates mixing of algal DMSP and the enzyme DMSP

Gordon V. Wolfe; Michael Steinke; Gunter O. Kirst

1997-01-01

319

Spectral shifting by dyes to enhance algae growth.  

PubMed

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 3x10(-5)M with tungsten filament lamp sources. PMID:18551655

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

1984-11-01

320

Rapid Biopolymerisation During Wound Plug Formation in Green Algae  

Microsoft Academic Search

Organisms living in the marine environment contain a number of primary and secondary metabolites which are involved in bioadhesive processes. Much progress has been made regarding the characterization of underwater adhesive structures utilized by sessile invertebrates such as barnacles, mussels, and tubeworms. The structural components and biochemical mechanisms involved in the wound-plug forming process in marine siphonous green algae have

Matthew Welling; Georg Pohnert; Frithjof C. Kpper; Cliff Ross

2009-01-01

321

Certain metals in three coastal algae from Ras Beirut waters  

Microsoft Academic Search

In July and August of 1977, samples of Halimeda tuna (Ellis & Solander) Lamouroux, Calpomenia sinuosa (Mertens & Roth) Derbes & Solier, and Pterocladia pinnata (Hudson) Papenfuss were collected along the coast of Ras Beirut, Lebanon and analyzed for lead, cadmium, copper, nickel and iron. The metal concentrations were quite similar in all three algae, except for iron, which was

J. G. Shiber; T. Shatila

1979-01-01

322

Ectocarpus: a model organism for the brown algae.  

PubMed

The brown algae are an interesting group of organisms from several points of view. They are the dominant organisms in many coastal ecosystems, where they often form large, underwater forests. They also have an unusual evolutionary history, being members of the stramenopiles, which are very distantly related to well-studied animal and green plant models. As a consequence of this history, brown algae have evolved many novel features, for example in terms of their cell biology and metabolic pathways. They are also one of only a small number of eukaryotic groups to have independently evolved complex multicellularity. Despite these interesting features, the brown algae have remained a relatively poorly studied group. This situation has started to change over the last few years, however, with the emergence of the filamentous brown alga Ectocarpus as a model system that is amenable to the genomic and genetic approaches that have proved to be so powerful in more classical model organisms such as Drosophila and Arabidopsis. PMID:22301644

Coelho, Susana M; Scornet, Delphine; Rousvoal, Sylvie; Peters, Nick T; Dartevelle, Laurence; Peters, Akira F; Cock, J Mark

2012-02-01

323

Toxins of a blue-green alga: similarity to saxitoxin.  

PubMed

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. PMID:5684499

Jackim, E; Gentile, J

1968-11-22

324

Testing an Algae-Based Air-Regeneration System.  

National Technical Information Service (NTIS)

The potential of an air-regeneration system based on the growth of unicellular algae on the surface of porous ceramic tubes was evaluated. The system is fairly robust with respect to environmental conditions and is capable of maintaining algal cultures fo...

J. Nienow

1998-01-01

325

[Phenol compounds from brown algae and their antioxidant activity].  

PubMed

The composition and content of phenolic substances were studied in 14 species of marine brown algae of the Canary Islands littoral (Spain). The highest content of phenolic substances was found in Cystoseira compressia and Sargassum furcatum. A high antioxidant activity was found in florotannin isolated from Cystoseira sp. PMID:10867955

Chkhikvishvili, I D; Ramazanov, Z M

326

Marine algae: screening for a potent antibacterial agent.  

PubMed

This study was done to investigate the antimicrobial potentiality of the marine algae collected from different coastal regions of Gujarat and screened for the same. Twenty-six marine algae belonging to Rhodophyceae, Chlorophyceae and Phaeophyceae were screened for their potential antibacterial activity against five clinically important bacterial strains, namely Bacillus cereus, Micrococcus flavus, Citrobacter freundii, Klebsiella pneumoniae and Pseudomonas testosterone. Acetone and methanol were used for extraction; and the extracted yield was more when the solvent used was methanol. The antibacterial activity was done by both Agar disc diffusion method and Agar ditch method. The five bacterial strains showed varied response towards marine algal extracts. The most susceptible bacteria was B. cereus followed by K. pneumoniae and C. freundii while the most resistant bacteria were M. flavus and P. testosteroni. Among the 26 algae screened, E. intestinalis was the most potent alga and thus, this alga was selected for further studies. E. intestinalis was extracted in petroleum ether, 1,4-dioxan, acetone, methanol and DMF, and their antibacterial activity was studied against the above-stated five bacterial strains using agar disc method. Maximum extractive value of E. intestinalis was in methanol (2.05%) and minimum was in acetone (0.38%). The most susceptible bacteria was K. pneumoniae and maximum antibacterial activity was shown by petroleum ether extract and minimum was shown by 1,4-dioxan extract. The most resistant bacteria were M. flavus and C. freundii. The MIC values of E. intestinalis extracts ranged from 2500-9.765 microg/0.5 ml against B. cereus and K. pneumoniae. From these results it is concluded that the acetone extract of E. intestinalis is the most potent extract and can be used as a lead molecule in drug discovery in inhibiting some of the bacterial strains. E. intestinalis can be used as a promising novel marine antimicrobial agent in the coming years. PMID:17594989

Nair, Ratish; Chabhadiya, Rajesh; Chanda, Sumitra

2007-01-01

327

Hostparasite relationship of the geoduck Panopea abbreviata and the green alga Coccomyxa parasitica in the Argentinean Patagonian coast  

Microsoft Academic Search

The association of the geoduck Panopea abbreviata and the green alga Coccomyxa parasitica is described. The identity of the green alga was confirmed by molecular studies; the alga was found within the hemocytes that infiltrate the connective tissue of the geoduck siphons. Cytological characteristics of hemocytes were not altered by algal infection; very often the algae were seen enveloped by

Nuria V嫙quez; Francisco Rodr璲uez; Cristi嫕 Ituarte; Javier Klaich; Florencia Cremonte

2010-01-01

328

Slow algae, fast fungi: exceptionally high nucleotide substitution rate differences between lichenized fungi Omphalina and their symbiotic green algae Coccomyxa  

Microsoft Academic Search

Omphalina basidiolichens are obligate mutualistic associations of a fungus of the genus Omphalina (the exhabitant) and a unicellular green alga of the genus Coccomyxa (the inhabitant). It has been suggested that symbiotic inhabitants have a lower rate of genetic change compared to exhabitants because the latter are more exposed to abiotic environmental variation and competition from other organisms. In order

Stefan Zoller; Fran蔞is Lutzoni

2003-01-01

329

Studies of marine epiphytic algae, Calvi, Corsica. II. Seasonal variations in the populations of epiphytic blue-green algae in three harbours with different pollution loads  

Microsoft Academic Search

Variations in the populations of blue-green algae epiphytic on Cladophora prolifera were studied quantitatively for a year in three harbours of contrasting water quality in the area of Calvi (Corsica). The development of blue-green algae was maximal in the summer and minimal in winter and spring, with some differences between the harbours. Density of filaments or colonies varied between 15

A. Wilmotte; V. Demoulin

1988-01-01

330

New type of alga photosynthesis activity modulation fluorometer in situ  

NASA Astrophysics Data System (ADS)

A developed in situ measuring system uses light emitted diodes (LED) and laser diodes(LD) as light sources is employed for the recording of algae chlorophyll fluorescence induction kinetics (Kautsky-effect). Photosynthesis activity as an important parameter is obtained in the system which measures the chlorophyll fluorescence yield. Minimal fluorescence is excited by the brief but really weak light pulses from LED as measure light while photosynthesis is happened, variable fluorescence which means there is energy conversion through photosynthesis is also excited by a LED but the beam is more stronger, LD induced saturation fluorescence stands for maximum fluorescence. The system could works for alga chlorophyll photosynthesis activity continuous measure in situ through efficiently mechanical and optical design.

Liu, Jing; Liu, Wenqing; Zhao, Nanjing; Zhang, Yujun; Yin, Gaofang; Dai, Pangda; Ma, Mingjun; Wang, Chunlong; Zhang, Wei; Duan, Jingbo; Fang, Li

2012-10-01

331

Biosorption of lead and nickel by biomass of marine algae.  

PubMed

Screening tests of different marine algae biomas types revealed a high passive biosorptive uptake of lead up to 270 mg Pb/g of biomass in some brown marine algae. Members of the order Fucales perfomed particularly well in this descending sequence: Fucus > Ascophyllum > Sargassum. Although decreasing the swelling of wetted biomass particles, their reinforcement by crosslinking may significantly affect the biosorption performance. Lead uptakes up to 370 mg Pb/g were observed in crosslinked Fucus vesiculosus and Ascophyllum nodosum. At low equilibrium residual concentrations of lead in solution, however, ion exchange resin Amberlite IR-120 had a higher lead uptake than the biosorbent materials. An order-of-magnitude lower uptake of nickel was observed in all of the sorbent materials examined. (c) 1994 John Wiley & Sons, Inc. PMID:18615510

Holan, Z R; Volesky, B

1994-05-01

332

Proton channels in algae: reasons to be excited.  

PubMed

A fundamental requirement of all eukaryotes is the ability to translocate protons across membranes. This is critical in bioenergetics, for compartmentalized metabolism, and to regulate intracellular pH (pH(i)) within a range that is compatible with cellular metabolism. Plants, animals, and algae utilize specialized transport machinery for membrane energization and pH homeostasis that reflects the prevailing ionic conditions in which they evolved. The recent characterization of H(+)-permeable channels in marine and freshwater algae has led to the discovery of novel functions for these transport proteins in both cellular pH homeostasis and sensory biology. Here we review the potential implications for understanding the origins and evolution of membrane excitability and the phytoplankton-based marine ecosystem responses to ocean acidification. PMID:22819465

Taylor, Alison R; Brownlee, Colin; Wheeler, Glen L

2012-07-21

333

Potential energy production from algae on marginal land in China.  

PubMed

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

Zhang, Qingtao; Ma, Jiong; Qiu, Guoyu; Li, Li; Geng, Shu; Hasi, E; Li, Cheng; Wang, Guangyi; Li, Xiaoyan

2011-08-31

334

Effect of the insecticide Zectran (Mexacarbate) on several algae  

Microsoft Academic Search

Summary Field samples of freshwater algae were examined to determine the effect of the insecticide Zectran on photosynthesis rate. Concentrations of Zectran between 10 and 103 parts per billion (ppb) affected neither O2 production nor NaH14CO3 uptake in any of the seven genera tested. However, Zectran at a concentration of 104 ppb after 1 hour effected a reduction in photosynthesis

Richard P. Sheridan; Marlene A. Simms

1975-01-01

335

Nuevas Especies de Algas de Agua Dulce Italiano-Espa隳las  

Microsoft Academic Search

Este modesto, deslabazado e insignificante trabajo de Algas de agua dulce, se lo dedico con mucho cari, veneraci y respeto, al gran maestro de la Ficologia Prof. De Toni (q. e. p.d.).Las tres especies nuevas y la variedad, se las dedico a 幨. Oedogonium De-Tonii, Phythelios De-Tonii y Rivularia beccariana var. De toniana, han sido cogidas en las aguas dulces

Pedro Gonz嫮ez Guerrero

1964-01-01

336

Reduction of Ferrrihydrite and Akaganeite by Shewanella alga (PAH93)  

Microsoft Academic Search

Shewanella species are capable of oxidizing diverse organic acids coupled to reducing Fe(III) (oxy)hydroxides to crystalline Fe(II)-containing phases such as magnetite, siderite, and vivianite. The objective of this study was to examine reduction of ferrihydrite and akaganeite as the electron acceptors using various organic acids as the electron donors by Shewanella alga (PAH93) isolated from Yeosu, South Korea. Microbial reduction

M. Jung; Y. Kim; Y. Lee; K. Kwon; Y. Roh

2009-01-01

337

Ribosomes from the blue-green alga Anabaena variabilis  

Microsoft Academic Search

Extracts from the blue-green alga Anabaena variabilis were prepared by ultrasonic disintegration or by extrusion through a French pressure cell; examination by sucrose density gradient centrifugation and analytical ultracentrifugation indicated the existence of a procaryotic (70S) ribosome. However both the ribosomes and their sub-units were found to be relatively unstable after isolation and examination in tris buffer pH 7.4 but

I. W. Craig; N. G. Carr

1968-01-01

338

Green algae in tundra soils affected by coal mine pollutions  

Microsoft Academic Search

Green algal communities were investigated in clean and pollution-impacted tundra soils around the large coal mine industrial\\u000a complex of Vorkuta in the E. European Russian tundra. Samples were collected in three zones of open-cast coal mining with\\u000a different degrees of pollution-impacted soil transformation. A total of 42 species of algae were found in all zones. The species\\u000a richness decreased from

Elena N. Patova; Marina F. Dorokhova

2008-01-01

339

Sustainability and cyanobacteria (blue-green algae): facts and challenges  

Microsoft Academic Search

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

Naveen K. Sharma; Sri Prakash Tiwari; Keshwanand Tripathi; Ashwani K. Rai

340

Chemical constituents of the red alga Laurencia tristicha  

Microsoft Academic Search

Six new sesquiterpenes, 10-hydroxy-epiaplysin (1), 10-hydroxy-aplysin (2), 10-hydroxy-debromoepiaplysin (3), aplysin-9-ene (4), epiaplysinol (5) and debromoepiaplysinol (6), together with 13 known compounds (719), have been isolated from the red alga Laurencia tristicha. The structures of 16 were determined by spectroscopic methods including IR, EI-MS, HREI-MS, and 1D and 2D NMR techniques. All compounds were obtained from this species for the first

JIE Sun; DA-YONG Shi; SHUAI Li; SU-JUAN Wang; LI-JUN Han; XIAO Fan; YONG-CHUN Yang; JIAN-GONG Shi

2007-01-01

341

Gamete recognition during fertilization in a red alga, Antithamnion nipponicum  

Microsoft Academic Search

Summary Fertilization in the marine red algaAntithamnion nipponicum is a highly specific process involving non-motile male gametes, spermatia, and female receptive structures, carpogonia. FITC-lectin and Calcofluor white ST labelling show that the outer cell walls of spermatia differ from vegetative cells in carbohydrate composition. Specific binding of the lectins to spermatial walls was confirmed by lectin-gold labelling on thin sections.

G. H. Kim; L. Fritz

1993-01-01

342

Survival and reproduction in some algae under stress conditions  

Microsoft Academic Search

Pithophora oedogonia andCladophora glomerata survived lowest 60 and 58 %, respectively, in June when the pond diurnal water temperature (PDWT) increased to a maximum\\u000a of 28 蚓. The lowering of PDWT only by 1 蚓 in July improved survivability of both algae to their almost maximum level of\\u000a 100 and 96 %, respectively. Further lowering of PDWT to 1722 蚓

S. Gupta; S. C. Agrawal

2007-01-01

343

How the green alga Chlamydomonas reinhardtii keeps time  

Microsoft Academic Search

The unicellular green alga Chlamydomonas reinhardtii has two flagella and a primitive visual system, the eyespot apparatus, which allows the cell to phototax. About 40years\\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

Thomas Schulze; Katja Prager; Hannes Dathe; Juliane Kelm; Peter Kie羦ing; Maria Mittag

2010-01-01

344

Changes of Algae Protein Complex under pH Effect  

Microsoft Academic Search

It was established that blue liquid formed in the decomposition of blue-green algae (Cyanophyta, Cyanobacteria) results from isolation of water-soluble bilichromoproteins from the cells, mainly phycocyanine and its derivatives, with\\u000a the zone of principal absorption maximum within the limits of 610630 ?m. The most stable color and spectral peculiarities\\u000a the liquid preserves at pH 6.87.2. It was shown that alkalization

Tatyana V. Parshikova

345

Calcium-dependent protein kinase in the green alga Chara  

Microsoft Academic Search

Cytoplasmic streaming in the characean algae is inhibited by micromolar rises in the level of cytosolic free Ca2+, but both the mechanism of action and the molecular components involved in this process are unknown. We have used monoclonal antibodies against soybean Ca2+-dependent protein kinase (CDPK), a kinase that is activated by micromolar Ca2+ and co-localizes with actin filaments in higher-plant

David W. McCurdy; Alice C. Harmon

1992-01-01

346

Long-term viability of preserved eukaryotic algae  

Microsoft Academic Search

Levels of viability of Chlorella emersonii after storage of dried material for one year were 0.1% on rehydration, all other\\u000a dried organisms examined in this study failed to recover after prolonged storage. In addition, no detectable recovery was\\u000a observed in any of the algae tested after storage of freeze-dried cultures. Methods have also been developed to cryopreserve\\u000a a range of

John G. Day; Makoto M. Watanabe; G. John Morris; Roland A. Fleck; Mark R. McLellan

1997-01-01

347

Brominated Selinane Sesquiterpenes from the Marine Brown Alga Dictyopteris divaricata  

PubMed Central

Two new brominated selinane sesquiterpenes, 1-bromoselin-4(14),11-diene (1) and 9-bromoselin-4(14),11-diene (2), one known cadinane sesquiterpene, cadalene (3), and four known selinane sesquiterpenes, ?-selinene (4), ?-selinene (5), ?-dictyopterol (6), and cyperusol C (7), were isolated from a sample of marine brown alga Dictyopteris divaricata collected off the coast of Yantai (China). Their structures were established by detailed MS and NMR spectroscopic analysis, as well as comparison with literature data.

Ji, Nai-Yun; Wen, Wei; Li, Xiao-Ming; Xue, Qin-Zhao; Xiao, Hua-Ling; Wang, Bin-Gui

2009-01-01

348

Detailed study of anaerobic digestion of Spirulina maxima algae biomass  

Microsoft Academic Search

Biomass of the blue-green alga Spirulina maxima was converted to methane using continuous stirred tank digesters with an energy conversion efficiency of 59%. Digesters were operated using once-a-day feeding with a retention time (theta) between 5 and 40 days, volatile solid concentrations (Sto) between 20 and 100 kg VS\\/cubic m, and temperatures between 15 and 52簞C. The results indicated a

R嶴ean Samson; A. LeDuy

1986-01-01

349

State 1\\/State 2 changes in higher plants and algae  

Microsoft Academic Search

Current ideas regarding the molecular basis of State 1\\/State 2 transitions in higher plants and green algae are mainly centered around the view that excitation energy distribution is controlled by phosphorylation of the light-harvesting complex of photosystem II (LHC-II). The evidence supporting this view is examined and the relationship of the transitions occurring in these systems to the corresponding transitions

W. Patrick Williams; John F. Allen

1987-01-01

350

INVESTIGATION OF PHOTOSYNTHETIC BACTERIA AND ALGAE BY RESONANCE RAMAN SPECTROSCOPY  

Microsoft Academic Search

Cyanobacteria and algae comprise a large and diverse group of organisms that are widely distributed in freshwater, marine, terrestrial, and extreme environments. Cyanobacterial and algal identification and classification rely on morphological characterization and 16S rRNA gene sequence analysis. Morphology however, can be misleading in certain circumstances, while 16S rRNA gene sequencing can be time consuming. Analysis of pigments that have

Craig P. MARSHALL; Stefan LEUKO

351

A simple classification of the volvocine algae by formal languages  

Microsoft Academic Search

There are several explanations of why certain primitive multicellular organisms aggregate in particular forms and why their\\u000a constituent cells cooperate with one another to a particular degree. Utilizing the framework of formal language theory, we\\u000a have derived one possible simple classification of the volvocine algaeone of the primitive multicellsfor some forms of aggregation\\u000a and some degrees of cooperation among cells.

Hiroshi Yoshida; Takashi Yokomori; Akira Suyama

2005-01-01

352

Unearthing the Molecular Phylodiversity of Desert Soil Green Algae (Chlorophyta)  

Microsoft Academic Search

Abstract.Deserts are not usually considered biodiversity hotspots, but desert microbiotic crust communities exhibit a rich diversity of both eukaryotic and prokaryotic life forms. Like many communities dominated by microscopic organisms, they defy characterization by traditional species-counting approaches,to assessing biodiversity. Here we use exclusive molecular phylodiversity,(E )t oquantify the amount,of evolutionary,divergence,unique,to desert-dwelling green algae (Chlorophyta) in microbiotic crust communities.,Given a phylogenetic,tree

LOUISE A. LEWIS; PAUL O. LEWIS

2005-01-01

353

Glycolipids from the red alga Chondria armata (Kutz.) Okamura  

Microsoft Academic Search

Three distinct fractions containing polar glycolipids (PF1-3) were isolated from the chloroform soluble fraction of crude methanolic extract of red alga Chondria armata (Ktz.) 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

Ammar Al-Fadhli; Solimabi Wahidulla; Lisette D'Souza

2006-01-01

354

Cytotoxic hydroazulene diterpenes from the brown alga Cystoseira myrica.  

PubMed

Cytotoxicity-guided fractionation of the alcohol extract of the brown alga, Cystoseira myrica, afforded four new cytotoxic hydroazulene diterpenes, dictyone acetate (2), dictyol F monoacetate (4), isodictytriol monoacetate (6), and cystoseirol monoacetate (8), together with two known cytotoxic hydroazulene diterpenes, pachydictyol A (1) and dictyone (3). The constitution of each isolated compound has been determined on the basis of spectroscopic and chemical evidence. PMID:12622222

Ayyad, Seif-Eldin N; Abdel-Halim, Osama B; Shier, W Thomas; Hoye, Thomas R

355

Ultraviolet sunscreen compounds in epiphytic red algae from mangroves  

Microsoft Academic Search

Epiphytic red algae of the order Ceramiales from mangroves and salt marshes (nine species from Bostrychia, three from Stictosiphonia and four from Caloglossa) produce varying levels of the UV-absorbing compounds mycosporine-glycine, shinorine, porphyra-334, palythine, asterina-330 and palythinol, a suite of substances chemically assigned as mycosporine-like amino acids (MAAs). Mean MAA levels varied from 0.02 to 12.8 mg g-1 DW in

Ulf Karsten; Thomas Sawall; John West; Christian Wiencke

2000-01-01

356

Cytoarchitecture of the desiccation-tolerant green alga Zygogonium ericetorum  

Microsoft Academic Search

In this study, the filamentous green alga Zygogonium ericetorum (Zygnematales, Chlorophyta), collected at its natural habitat in the high alps, was investigated by light, scanning, and\\u000a transmission electron microscopy. The field samples were separated into a moist fraction when wetted by splattering water\\u000a of a nearby spring or a desiccated one when visually dried out. Light microscopy demonstrated a purple

A. Holzinger; A. Tschaikner; D. Remias

2010-01-01

357

Partitioning of monomethylmercury between freshwater algae and water.  

PubMed

Phytoplankton-water monomethylmercury (MeHg) partition constants (KpI) have been determined in the laboratory for two green algae Selenastrum capricornutum and Cosmarium botrytis, the blue-green algae Schizothrix calcicola, and the diatom Thallasiosira spp., algal species that are commonly found in natural surface waters. Two methods were used to determine KpI, the Freundlich isotherm method and the flow-through/dialysis bag method. Both methods yielded KpI values of about 10(6.6) for S. capricornutum and were not significantly different. The KpI for the four algae studied were similar except for Schizothrix, which was significantly lower than S. capricornutum. The KpI for MeHg and S. capricornutum (exponential growth) was not significantly different in systems with predominantly MeHgOH or MeHgCl species. This is consistent with other studies that show metal speciation controls uptake kinetics, but the reactivity with intracellular components controls steady-state concentrations. Partitioning constants determined with exponential and stationary phase S. capricornutum cells at the same conditions were not significantly different, while the partitioning constant for exponential phase, phosphorus-limited cells was significantly lower, suggesting that P-limitation alters the ecophysiology of S. capricornutum sufficiently to impact partitioning, which may then ultimately affect mercury levels in higher trophic species. PMID:11718342

Miles, C J; Moye, H A; Phlips, E J; Sargent, B

2001-11-01

358

An exogenous chloroplast genome for complex sequence manipulation in algae  

PubMed Central

We demonstrate a system for cloning and modifying the chloroplast genome from the green alga, Chlamydomonas reinhardtii. Through extensive use of sequence stabilization strategies, the ex vivo genome is assembled in yeast from a collection of overlapping fragments. The assembled genome is then moved into bacteria for large-scale preparations and transformed into C. reinhardtii cells. This system also allows for the generation of simultaneous, systematic and complex genetic modifications at multiple loci in vivo. We use this system to substitute genes encoding core subunits of the photosynthetic apparatus with orthologs from a related alga, Scenedesmus obliquus. Once transformed into algae, the substituted genome recombines with the endogenous genome, resulting in a hybrid plastome comprising modifications in disparate loci. The in vivo function of the genomes described herein demonstrates that simultaneous engineering of multiple sites within the chloroplast genome is now possible. This work represents the first steps toward a novel approach for creating genetic diversity in any or all regions of a chloroplast genome.

O'Neill, Bryan M.; Mikkelson, Kari L.; Gutierrez, Noel M.; Cunningham, Jennifer L.; Wolff, Kari L.; Szyjka, Shawn J.; Yohn, Christopher B.; Redding, Kevin E.; Mendez, Michael J.

2012-01-01

359

A cytotoxic hydroperoxy sterol from the brown alga, Nizamuddinia zanardinii  

PubMed Central

Background The marine environment is a unique source of bioactive natural products, of which Nizamuddinia zanardinii is an important brown algae distributed in Oman Sea. Literature revealed that there is no report on phytochemistry and pharmacology of this valuable algae. Methods Bioguided fractionation of the methanolic extract of Nizamuddinia zanardinii, collected from Oman Sea, led to the isolation of a hydroperoxy sterol. Its structure was determined by analysis of the spectroscopic data as 24-hydroperoxy-24-vinyl cholesterol (HVC). In vitro cytotoxic activity of this compound was evaluated against HT29, MCF7, A549, HepG2 and MDBK cell lines. Results Although 24(R)-hydroproxy-24-vinylcholesterol has been previously reported from Sargassum and Padina species, it is the first report on the presence of this compound from N. zanardinii. This compound exhibited cytotoxicity in all cell lines (IC50, 3.62, 9.09, 17.96, 32.31 and 37.31??g/mL respectively). HVC was also evaluated for apoptotic activity and demonstrated positive results in terminal deoxynucleotidyl transferase dUTP Nick End labeling (TUNEL) assay suggesting it a candidate for further apoptotic studies. Conclusions Nizamuddinia zanardinii, a remarkable brown algae of Oman Sea, is a good source of hydroproxy sterols with promising cytotoxic on various cell lines particularly human colon adenocarcinoma.

2013-01-01

360

Distribution of periphytic algae in wetlands (Palm swamps, Cerrado), Brazil.  

PubMed

The distribution of periphytic algae communities depends on various factors such as type of substrate, level of disturbance, nutrient availability and light. According to the prediction that impacts of anthropogenic activity provide changes in environmental characteristics, making impacted Palm swamps related to environmental changes such as deforestation and higher loads of nutrients via allochthonous, the hypothesis tested was: impacted Palm swamps have higher richness, density, biomass and biovolume of epiphytic algae. We evaluated the distribution and structure of epiphytic algae communities in 23 Palm swamps of Goi嫳 State under different environmental impacts. The community structure attributes here analyzed were composition, richness, density, biomass and biovolume. This study revealed the importance of the environment on the distribution and structuration of algal communities, relating the higher values of richness, biomass and biovolume with impacted environments. Acidic waters and high concentration of silica were important factors in this study. Altogether 200 taxa were identified, and the zygnemaphycea was the group most representative in richness and biovolume, whereas the diatoms, in density of studied epiphyton. Impacted Palm swamps in agricultural area presented two indicator species, Gomphonema lagenula Ktzing and Oedogonium sp, both related to mesotrophic to eutrophic conditions for total nitrogen concentrations of these environments. PMID:23917560

Dunck, B; Nogueira, I S; Felisberto, S A

2013-05-01

361

An exogenous chloroplast genome for complex sequence manipulation in algae.  

PubMed

We demonstrate a system for cloning and modifying the chloroplast genome from the green alga, Chlamydomonas reinhardtii. Through extensive use of sequence stabilization strategies, the ex vivo genome is assembled in yeast from a collection of overlapping fragments. The assembled genome is then moved into bacteria for large-scale preparations and transformed into C. reinhardtii cells. This system also allows for the generation of simultaneous, systematic and complex genetic modifications at multiple loci in vivo. We use this system to substitute genes encoding core subunits of the photosynthetic apparatus with orthologs from a related alga, Scenedesmus obliquus. Once transformed into algae, the substituted genome recombines with the endogenous genome, resulting in a hybrid plastome comprising modifications in disparate loci. The in vivo function of the genomes described herein demonstrates that simultaneous engineering of multiple sites within the chloroplast genome is now possible. This work represents the first steps toward a novel approach for creating genetic diversity in any or all regions of a chloroplast genome. PMID:22116061

O'Neill, Bryan M; Mikkelson, Kari L; Gutierrez, Noel M; Cunningham, Jennifer L; Wolff, Kari L; Szyjka, Shawn J; Yohn, Christopher B; Redding, Kevin E; Mendez, Michael J

2011-11-23

362

Measurement of Carbon Dioxide Compensation Points of Freshwater Algae 1  

PubMed Central

A technique is described for the measurement of total dissolved inorganic carbon by acid release as CO2 followed by its conversion to methane and detection by flame ionization in a modified gas chromatograph. This method was used to determine the dissolved inorganic carbon concentration reached at compensation point when algae were allowed to photosynthesize in a closed system in a buffer at known pH, and the CO2 compensation point was calculated from this concentration. The CO2 compensation points of 16 freshwater algae were measured at acid and alkaline pH in air-saturated medium: at acid pH the CO2 compensation points ranged from 4.8 to 41.5 microliters per liter while at alkaline pH they ranged from 0.2 to 7.2 microliters per liter. Removal of O2 from the medium caused a slight lowering of compensation point at acid pH but had little effect at alkaline pH. These low, O2-insensitive compensation points are characteristic of C4 plants. It is suggested that these low CO2 compensation points are maintained by an active bicarbonate uptake by algae especially at alkaline pH.

Birmingham, Brendan C.; Colman, Brian

1979-01-01

363

Cytotoxicity of algae extracts on normal and malignant cells.  

PubMed

Algae preparations are commonly used in alternative medicine. We examined the effects of algae extracts on normal hematopoietic cells and leukemia cells. Ethanol extracts were prepared of Dunaliella salina (Dun), Astaxanthin (Ast), Spirulina platensis (Spir), and Aphanizomenon flos-aquae (AFA). Cell viability effects were completed by Annexin staining. Ast and AFA inhibited HL-60 and MV-4-11 whereas Dun and Spir had no effect. Primary AML blasts demonstrated increased apoptosis in AFA. Primary CLL cells showed apoptosis at 24 hours after exposure to Dun, Ast, Spir, and AFA. High AFA concentrations decreased viability of normal marrow cells. Normal CD34+ viability was inhibited by Dun. Dun and AFA inhibited BFU-E, but all extracts inhibited CFU-GM. Cell-cycle analysis of AML cell lines showed G0/G1 arrest in the presence of AFA. These data suggest that algae extracts may inhibit AML cell lines and leukemia blasts, but they may also have potential inhibitory effects on normal hematopoiesis. PMID:23213541

Bechelli, Jeremy; Coppage, Myra; Rosell, Karen; Liesveld, Jane

2011-01-05

364

Cytotoxicity of Algae Extracts on Normal and Malignant Cells  

PubMed Central

Algae preparations are commonly used in alternative medicine. We examined the effects of algae extracts on normal hematopoietic cells and leukemia cells. Ethanol extracts were prepared of Dunaliella salina (Dun), Astaxanthin (Ast), Spirulina platensis (Spir), and Aphanizomenon flos-aquae (AFA). Cell viability effects were completed by Annexin staining. Ast and AFA inhibited HL-60 and MV-4-11 whereas Dun and Spir had no effect. Primary AML blasts demonstrated increased apoptosis in AFA. Primary CLL cells showed apoptosis at 24 hours after exposure to Dun, Ast, Spir, and AFA. High AFA concentrations decreased viability of normal marrow cells. Normal CD34+ viability was inhibited by Dun. Dun and AFA inhibited BFU-E, but all extracts inhibited CFU-GM. Cell-cycle analysis of AML cell lines showed G0/G1 arrest in the presence of AFA. These data suggest that algae extracts may inhibit AML cell lines and leukemia blasts, but they may also have potential inhibitory effects on normal hematopoiesis.

Bechelli, Jeremy; Coppage, Myra; Rosell, Karen; Liesveld, Jane

2011-01-01

365

Uptake and distribution of technetium in several marine algae  

SciTech Connect

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.

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

366

Ecology of planktonic foraminifera and their symbiotic algae  

SciTech Connect

Two types of symbiotic algae occurred abundantly and persistently in the cytoplasm of several species of planktonic Foraminifera over a ten year period in different tropical and subtropical areas of the North Atlantic Ocean. These planktonic Foraminifera host species consistently harbored either dinoflagellates or a newly described minute coccoid algal type. There appeared to be a specific host-symbiont relationship in these species regardless of year, season or geographic locality. The larger ovoid dinoflagellates (Pyrrhophycophyta) occur in the spinose species Globigerinoides ruber, Globigerinoides sacculifer, G. conglobatus and Orbulina universa. The smaller alga, from 1.5 to 3.5 um in diameter, occurs in one spinose species Globigerinella aequilateralis and also in the non-spinose species Globigerinita glutinata, Globoquadrina dutertrei, Globorotalia menardii, Globorotalia cristata, Globorotalia inflata, Candeina nitida, in various juvenile specimens and at all seasons except the winter months in Pulleniatina obliquiloculata and Globorotalial hirsuta. Controlled laboratory studies indicated a significant C incorporation into the host cytoplasm and inorganic calcium carbonate test of Globigerinoides ruber. During incubation for up to two hours, the /sup 14/C uptake into the cytoplasm and test in the light was significantly greater than uptake in the dark by living specimens or by dead foraminifers. There appears to be light-enhanced uptake of /sup 14/C into the test with dinoflagellate photosynthesis contributing to host calcification. In culture, symbiotic algae were observed to survive for the duration of the lifespan of their hosts.

Gastrich, M.D.

1986-01-01

367

Anti-diabetic effects of brown algae derived phlorotannins, marine polyphenols through diverse mechanisms.  

PubMed

Marine algae are popular and abundant food ingredients mainly in Asian countries, and also well known for their health beneficial effects due to the presence of biologically active components. The marine algae have been studied for biologically active components and phlorotannins, marine polyphenols are among them. Among marine algae, brown algae have extensively studied for their potential anti-diabetic activities. Majority of the investigations on phlorotannins derived from brown algae have exhibited their various anti-diabetic mechanisms such as ?-glucosidase and ?-amylase inhibitory effect, glucose uptake effect in skeletal muscle, protein tyrosine phosphatase 1B (PTP 1B) enzyme inhibition, improvement of insulin sensitivity in type 2 diabetic db/db mice, and protective effect against diabetes complication. In this review, we have made an attempt to discuss the various anti-diabetic mechanisms associated with phlorotannins from brown algae that are confined to in vitro and in vivo. PMID:23466874

Lee, Seung-Hong; Jeon, You-Jin

2013-03-04

368

Enhancement of Taihu blue algae anaerobic digestion efficiency by natural storage.  

PubMed

Taihu blue algae after different storage time from 0 to 60d were anaerobic fermented to evaluate their digestibility and process stability. Results showed that anaerobic digestion (AD) of blue algae under 15d natural storage led to the highest CH4 production of 287.6mLg(-1) VS at inoculum substrate ratio 2.0, demonstrating 36.69% improvement comparing with that from fresh algae. Storage of blue algae led to cell death, microcystins (MCs) release and VS reduction by spontaneous fermentation. However, it also played an important role in removing algal cell wall barrier, pre-hydrolysis and pre-acidification, leading to the improvement in CH4 yield. Closer examination of volatile fatty acids (VFA) variation, VS removal rates and key enzymes change during AD proved short storage time (?15d) of blue algae had higher efficiencies in biodegradation and methanation. Furthermore, AD presented significant biodegradation potential for MCs released from Taihu blue algae. PMID:24128398

Miao, Hengfeng; Lu, Minfeng; Zhao, Mingxing; Huang, Zhenxing; Ren, Hongyan; Yan, Qun; Ruan, Wenquan

2013-09-27

369

Sustainable Bioenergy Bioprocessing: Biomethane Production, Digestate as Biofertilizer and as Supplemental Feed in Algae Cultivation to Promote Algae Biofuel Commercialization  

Microsoft Academic Search

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

Gene Drekeke Iyovo; Guocheng Du; Jian Chen

2010-01-01

370

Sludge-grown algae for culturing aquatic organisms: Part II. Sludge-grown algae as feeds for aquatic organisms  

NASA Astrophysics Data System (ADS)

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.

Wong, M. H.; Hung, K. M.; Chiu, S. T.

1996-05-01

371

The Future is Green: On the Biotechnological Potential of Green Algae  

Microsoft Academic Search

\\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

Werner Reisser

372

Diel tuning of photosynthetic systems in ice algae at Saroma-ko Lagoon, Hokkaido, Japan  

Microsoft Academic Search

Ice algae are the major primary producers in seasonally ice-covered oceans during the cold season. Diurnal change in solar radiation is inevitable for ice algae, even beneath seasonal sea ice in lower-latitude regions. In this work, we focused on the photosynthetic response of ice algae under diurnally changing irradiance in Saroma-ko Lagoon, Japan. Photosynthetic properties were assessed by pulse-amplitude modulation

Shimpei Aikawa; Hiroshi Hattori; Yasushi Gomi; Kentaro Watanabe; Sakae Kudoh; Yasuhiro Kashino; Kazuhiko Satoh

2009-01-01

373

R犨e of blue-green algae and different methods of partial soil sterilization on rice yield  

Microsoft Academic Search

SummaryResults of experiments during three consecutive seasons on the r犨e of blue-green algae in combination with partial soil sterilization\\u000a and chemical nutrients indicate high responses to algae inoculation and a fertility build-up of the soil. It is also seen\\u000a that blue-green algae tend to produce better response in soils which are poor.

R. Subrahmanyan; L. L. Relwani; G. B. Manna

1964-01-01

374

Gain and loss of polyadenylation signals during evolution of green algae  

Microsoft Academic Search

BACKGROUND: The Viridiplantae (green algae and land plants) consist of two monophyletic lineages: the Chlorophyta and the Streptophyta. Most green algae belong to the Chlorophyta, while the Streptophyta include all land plants and a small group of freshwater algae known as Charophyceae. Eukaryotes attach a poly-A tail to the 3' ends of most nuclear-encoded mRNAs. In embryophytes, animals and fungi,

Sabina Wodniok; Andreas Simon; Gernot Gl鐼kner; Burkhard Becker

2007-01-01

375

The measurement and significance of ATP pools in filamentous blue-green algae  

Microsoft Academic Search

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

P. J. Bottomley; W. D. P. Stewart

1976-01-01

376

Equilibrium and kinetics studies of heavy metal ions biosorption on green algae waste biomass  

Microsoft Academic Search

The biosorption of Pb(II), Cd(II), and Co(II), respectively, from aqueous solution on green algae waste biomass was investigated. The green algae waste biomass was obtained from marine green algae after extraction of oil, and was used as low-cost biosorbent. Batch shaking experiments were performed to examine the effects of initial solution pH, contact time and temperature. The equilibrium biosorption data

Dumitru Bulgariu; Laura Bulgariu

377

Photoreduction of chromium(VI) in the presence of algae, Chlorella vulgaris  

Microsoft Academic Search

In this thesis, the photochemical reduction of hexavalent chromium Cr(VI) in the presence of algae, Chlorella vulgaris, was investigated under the irradiation of metal halide lamps (?=365nm, 250W). The affecting factors of photochemical reduction were studied in detail, such as exposure time, initial Cr(VI) concentration, initial algae concentration and pH. The rate of Cr(VI) photochemical reduction increased with algae concentration

Lin Deng; Hongli Wang; Nansheng Deng

2006-01-01

378

Removal of copper using marine brown alga, Undaria Pinnatifida modified with oxime  

Microsoft Academic Search

As oxime is selective for Cu2+, oxime groups were introduced to the cell wall of alga by glutaraldehyde. Such modified biomass showed high affinity for Cu2+, which resulted in the increase of copper sorption capacity about 4.5 times higher than that of natural alga. For pH range from 2.5 to 3.0, only Cu2+ were removed by alga biomass modified with

Yong Hwan Kim; Jae Yeon Park; Young Je Yoo; Byung Ik Ryoot; Won Woo Lee

1996-01-01

379

Benthic Algae in High Altitude Streams of the Alps a Neglected Component of the Aquatic Biota  

Microsoft Academic Search

This is a review on benthic algae from streams situated above the tree line in the Alps. It integrates published and unpublished\\u000a data from alpine streams in Austria and in the Trento Province (Northern Italy). The main focus is on the structural and taxonomic\\u000a composition of benthic algae including macro- and micro-algae and their contribution to the epilithic biofilm and

E. Rott; M. Cantonati; L. Freder; P. Pfister

2006-01-01

380

The salt relations of marine and halophilic species of the unicellular green alga, Dunaliella  

Microsoft Academic Search

1.Comparisons were made of the effects of salt on the exponential growth rates of two unicellular algae,Dunaliella tertiolecta (marine) andDunaliella viridis (halophilic).2.The algae contained glycerol in amounts which varied directly with the salt concentration of the growth media. The highest measured glycerol content ofD. tertiolecta was approximately equivalent to 1.4 molal and occurred in algae grown in 1.36 M sodium

Lesley Joyce Borowitzka; Austin Duncan Brown

1974-01-01

381

Detection and activity of iodine-131 in brown algae collected in the Japanese coastal areas  

Microsoft Academic Search

Iodine-131 (physical half-life: 8.04days) was detected in brown algae collected off the Japanese coast. Brown algae have been extensively used as bioindicators for radioiodine because of their ability to accumulate radionuclides in high concentration factors. The maximum measured specific activity of 131I in brown algae was 0.370.010Bq\\/kg-wet. Cesium-137 was also detected in all brown algal samples used in this study.

Takami Morita; Kentaro Niwa; Ken Fujimoto; Hiromi Kasai; Haruya Yamada; Kou Nishiutch; Tatsuya Sakamoto; Waichiro Godo; Seiya Taino; Yoshihiro Hayashi; Koji Takeno; Tomokazu Nishigaki; Kunihiro Fujiwara; Hisamichi Aratake; Shingo Kamonoshita; Hiroshi Hashimoto; Takuya Kobayashi; Sigeyoshi Otosaka; Tetsuji Imanaka

2010-01-01

382

Natural Abundance 14C Content of Dibutyl Phthalate (DBP) from Three Marine Algae  

PubMed Central

Analysis of the natural abundance 14C content of dibutyl phthalate (DBP) from two edible brown algae, Undaria pinnatifida and Laminaria japonica, and a green alga, Ulva sp., revealed that the DBP was naturally produced. The natural abundance 14C content of di-(2-ethylhexyl) phthalate (DEHP) obtained from the same algae was about 5080% of the standard sample and the 14C content of the petrochemical (industrial) products of DBP and DEHP were below the detection limit.

Namikoshi, Michio; Fujiwara, Takeshi; Nishikawa, Teruaki; Ukai, Kazuyo

2006-01-01

383

Design of a portable algae fluorometer based on an embedded system  

Microsoft Academic Search

With the use of the excitation fluorescence spectra of algae, Portable Algae Classification Fluorometer (PACF) made the rapid and in situ classified measurement of the algae come true. In order to improve real-time capability and stability of the system, a system-embedded instrument is designed based on ARM7 and muCOSII. The system, with the advantage of strong real-time and stability, small

Gao-Fang Yin; Yu-Jun Zhang; Zhi-Gang Wang; Li-Quan Guo; Xue Xiao; Dan Jin; Nan-Jing Zhao

2009-01-01

384

Algae of Peter the Great Bay of the Sea of Japan as a source of lectins  

Microsoft Academic Search

Algae of Peter the Great Bay (Sea of Japan) were for the first time bioassayed as a source of lectins. From 28 algal species\\u000a of three orders, only some extracts from brown (Phaeophyta) and red (Rhodophyta) seaweeds were found to cause agglutination\\u000a of human erythrocytes. The hemagglutinating activity of extracts from three species of brown algae and the red alga

O. V. Chernikov; I. V. Chikalovets; V. I. Molchanova; M. A. Pavlova; P. A. Lukyanov

2007-01-01

385

Endozoic algae in shelled gastropods a new symbiotic association in coral reefs?  

NASA Astrophysics Data System (ADS)

Endozoic microalgae were found in most snails collected from coral reefs and beachrock communities in the Red Sea. Algae were identified microscopically as well as by chromatography and spectrophotometry of pigment extracts. The algae were located in the hepatopancreas and the gonads, organs which are permanently concealed within the shell. According to pigment analysis, most of the endozoic algae belong the Chromophyta, perhaps dinoflagellates, except for a few chlorophytes.

Berner, T.; Wishkovsky, A.; Dubinsky, Z.

1986-10-01

386

Sulfuric acid in the phaeophyte alga Desmarestia munda deters feeding by the sea urchin Strongylocentrotus droebachiensis  

Microsoft Academic Search

The phaeophyte alga Desmarestia munda (Order Desmarestiales) concentrates sulfuric acid (H2SO4) in cell vacuoles. The primary function of the accumulated acid in the alga's life history is unknown. To investigate if sulfuric acid works as a chemical defense, grazing by the sea urchin herbivore Strongylocentrotus droebachiensis on D. munda was compared to grazing on four common non-acidic phaeophyte algae (Alaria

K. Pelletreau; G. Muller-Parker

2002-01-01

387

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...

388

Algae monitoring using Beijing-1 satellite: a case study in Qingdao neighbouring sea area, China  

NASA Astrophysics Data System (ADS)

Beijing-1 small satellite has three bands of green, red and near-infrared, with spatial resolution of 32 meters. Three days Beijing-1 data are used to retrieve distribution and living status of Enteromorpha clathrata (a kind of green algae and called Hutai in Chinese). First, use the non-supervised classification to separate the kinds who has big spectral differences. Second, the cloud and cloud-covered green algae can be separated by the ratio of near-infrared and red. In the end, the green algae distribution is obtained. The NDVI is used for indicator of living status and density. MODIS has the advantage of high temporal although its spatial resolution is much coarse than Beijing-1. A decision tree is developed to retrieve green algae. First, the cloud is eliminated by its high reflectance. Second, the NDVI is calculated and a threshold value is set to determine whether the grid is green algae. The green algae distribution results from Beijing-1 and MODIS are compared. Generally, the Beijing-1 extracted green algae is coincide with the MODIS extracted green algae. The Beijing-1 extracted algae area is smaller than that of MODIS, because the MODIS has spatial resolution of 250-meter, its situation of mix pixel is severer.

Chen, Zhenghua; Mao, Zhihua; Zou, Juhong; Ma, Qingyuan; Bai, Yan; He, Xianqiang

2009-01-01

389

How-to-Do-It: Diatoms: The Ignored Alga in High School Biology.  

ERIC Educational Resources Information Center

|Provides historical background, descriptions, uses and basis for identification of diatoms. Explains collection, dry-mount cleaning, and preparation procedures of the algae. Cites additional resources. (RT)|

Hungerford, James J.

1988-01-01

390

The effects of ProAlgaZyme novel algae infusion on metabolic syndrome and markers of cardiovascular health  

PubMed Central

Background Metabolic Syndrome, or Syndrome X, is characterized by a set of metabolic and lipid imbalances that greatly increases the risk of developing diabetes and cardiovascular disease. The syndrome is highly prevalent in the United States and worldwide, and treatments are in high demand. ProAlgaZyme, a novel and proprietary freshwater algae infusion in purified water, has been the subject of several animal studies and has demonstrated low toxicity even with chronic administration at elevated doses. The infusion has been used historically for the treatment of several inflammatory and immune disorders in humans and is considered well-tolerated. Here, the infusion is evaluated for its effects on the cardiovascular risk factors present in metabolic syndrome in a randomized double-blind placebo-controlled study involving 60 overweight and obese persons, ages 2560. All participants received four daily oral doses (1 fl oz) of ProAlgaZyme (N = 22) or water placebo (N = 30) for a total of 10 weeks, and were encouraged to maintain their normal levels of physical activity. Blood sampling and anthropometric measurements were taken at the beginning of the study period and after 4, 8 and 10 weeks of treatment. Eight participants did not complete the study. Results ProAlgaZyme brought about statistically significant (p < 0.001) reductions in the following: weight, body fat, total cholesterol, LDL-cholesterol, triglycerides, C-reactive protein and fasting blood glucose levels, accompanied by a significant (p < 0.001) increase in HDL-cholesterol levels over the 10-week study period. The infusion was well-tolerated and no side effects were noted. Conclusion ProAlgaZyme (4 fl oz daily) consumption resulted in significant reductions in weight and blood glucose levels, while significantly improving serum lipid profiles and reducing markers of inflammation, thus improving cardiovascular risk factors in overweight and obese subjects over a course of 10 weeks with an absence of adverse side effects. Trial Registration US ClinicalTrials.gov NCT00489333

Oben, Julius; Enonchong, Ebangha; Kuate, Dieudonne; Mbanya, Dora; Thomas, Tiffany C; Hildreth, DeWall J; Ingolia, Thomas D; Tempesta, Michael S

2007-01-01

391

Chemical examinations of some non-vascular Paleozoic plants  

Microsoft Academic Search

The organic chemical constituents of compression fossils ofNematothallus,Spongiophyton, Orestovia andEohostimella are identified and compared with those isolated from living and fossil forms ofBotryococcus (a green alga) andTaeniocrada (a vascular plant fossil). The range and maxima in the carbon numbers observed in the normal, saturated acids isolated fromNematothallus, Orestovia, andSpongiophyton are similar to those of fossilBotryococcus, while those acids contained within

Karl J. Niklas

1976-01-01

392

Selection of microalgae for lipid production under high levels carbon dioxide.  

PubMed

To select microalgae with a high biomass and lipid productivity, Botryococcus braunii, Chlorella vulgaris, and Scenedesmus sp. were cultivated with ambient air containing 10% CO(2) and flue gas. The biomass and lipid productivity for Scenedesmus sp. with 10% CO(2) were 217.50 and 20.65 mg L(-1)d(-1) (9% of biomass), while those for B. braunii were 26.55 and 5.51 mg L(-1)d(-1) (21% of biomass). With flue gas, the lipid productivity for Scenedesmus sp. and B. braunii was increased 1.9-fold (39.44 mg L(-1)d(-1)) and 3.7-fold (20.65 mg L(-1)d(-1)), respectively. Oleic acid, a main component of biodiesel, occupied 55% among the fatty acids in B. braunii. Therefore, the present results suggested that Scenedesmus sp. is appropriate for mitigating CO(2), due to its high biomass productivity and C-fixation ability, whereas B. braunii is appropriate for producing biodiesel, due to its high lipid content and oleic acid proportion. PMID:19362826

Yoo, Chan; Jun, So-Young; Lee, Jae-Yon; Ahn, Chi-Yong; Oh, Hee-Mock

2009-04-11

393

Carotenoid Biosynthesis in the Primitive Red Alga Cyanidioschyzon merolae?  

PubMed Central

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.

Cunningham, Francis X.; Lee, Hansel; Gantt, Elisabeth

2007-01-01

394

A new ketosteroid from red alga Acanthophora spicifera  

Microsoft Academic Search

A new ketosteroid, along with six known steroids, was isolated from the ethanolic extracts of red alga Acanthophora spicifera (Vahl.) Boergesen. The structures, identified using chemical and spectroscopic methods including 2D NMR, were: (1) 22-hydroxy-5?-cholest-3,6-dione, (2) 6-hydroxycholest-4-ene-3-one, (3) cholest-4-ene-3,6-dione, (4) cholest-5-ene-3?-ol, (5) 5?-cholestane-3,6-dione, (6) ?-Sitosterol and (7) Saringosterol. The MTT method was used to test the cytotoxicity of the compounds

Dayong Shi; Shuju Guo; Xiao Fan

2011-01-01

395

Chloroplast and mitochondrial DNA in a brown alga Egregia menziesii.  

PubMed

Chloroplasts and mitochondria of the brown alga Egregia menziesii were studied with the electron microscope. In both organelles, 15-25-A fibrils with DNA characteristics are found within areas of electron transparency. In each chloroplast there are two DNA-containing areas, one at each tip of the chloroplast. This localization, the shape and size of each DNA-containing area, and its close association with lamellae in a nondividing chloroplast are noted. One or occasionally two DNA-containing areas are found within the mitochondrion and they are compared with a similar structure in the chloroplast. PMID:6036520

Bisalputra, T; Bisalputra, A A

1967-06-01

396

Algicidal Sesquiterpene Hydroquinones from the Brown Alga Dictyopteris undulata.  

PubMed

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 痢/mL. PMID:23649244

Ishibashi, Fumito; Sato, Shun; Sakai, Kie; Hirao, Shotaro; Kuwano, Kazuyoshi

2013-05-07

397

Bioactivities from Marine Algae of the Genus Gracilaria  

PubMed Central

Seaweeds are an important source of bioactive metabolites for the pharmaceutical industry in drug development. Many of these compounds are used to treat diseases like cancer, acquired immune-deficiency syndrome (AIDS), inflammation, pain, arthritis, as well as viral, bacterial, and fungal infections. This paper offers a survey of the literature for Gracilaria algae extracts with biological activity, and identifies avenues for future research. Nineteen species of this genus that were tested for antibacterial, antiviral, antifungal, antihypertensive, cytotoxic, spermicidal, embriotoxic, and anti-inflammatory activities are cited from the 121 references consulted.

de Almeida, Cynthia Layse F.; Falcao, Heloina de S.; Lima, Gedson R. de M.; Montenegro, Camila de A.; Lira, Narlize S.; de Athayde-Filho, Petronio F.; Rodrigues, Luis C.; de Souza, Maria de Fatima V.; Barbosa-Filho, Jose M.; Batista, Leonia M.

2011-01-01

398

Comprehensive guide to acetyl-carboxylases in algae.  

PubMed

Lipids from microalgae have become an important commodity in the last 20 years, biodiesel and supplementing human diets with ?-3 fatty acids are just two of the many applications. Acetyl-CoA carboxylase (ACCase) is a key enzyme in the lipid synthesis pathway. In general, ACCases consist of four functional domains: the biotin carboxylase (BC), the biotin carboxyl binding protein (BCCP), and ?-and ?-carboxyltransferases (?-and ?-CT). In algae, like in plants, lipid synthesis is another function of the chloroplast. Despite being well researched in plants and animals, there is a distinct lack of information about this enzyme in the taxonomically diverse algae. In plastid-containing organisms, ACCases are present in the cytosol and the plastid (chloroplasts) and two different forms exist, the heteromeric (prokaryotic) and homomeric (eukaryotic) form. Despite recognition of the existence of the two ACCase forms, generalized published statements still list the heteromeric form as the one present in algal plastids. In this study, the authors show this is not the case for all algae. The presence of heteromeric or homomeric ACCase is dependent on the origin of plastid. The authors used ACCase amino acid sequence comparisons to show that green (Chlorophyta) and red (Rhodophyta) algae, with the exception of the green algal class Prasinophyceae, contain heteromeric ACCase in their plastids, which are of primary symbiotic origin and surrounded by two envelope membranes. In contrast, algal plastids surrounded by three to four membranes were derived through secondary endosymbiosis (Heterokontophyta and Haptophyta), as well as apicoplast containing Apicomplexa, contain homomeric ACCase in their plastids. Distinctive differences in the substrate binding regions of heteromeric and homomeric ?-CT and ?-CT were discovered, which can be used to distinguish between the two ACCase types. Furthermore, the acetyl-CoA binding region of homomeric ?-CT can be used to distinguish between cytosolic and plastidial ACCase. The information provided here will be of fundamental importance in ACCase expression and activity research to unravel impacts of environmental and physicochemical parameters on lipid content and productivity. PMID:22524446

Huerlimann, Roger; Heimann, Kirsten

2012-04-23

399

Antioxidative meroterpenoids from the brown alga Cystoseira crinita.  

PubMed

Six new tetraprenyltoluquinol derivatives (1-6), two new triprenyltoluquinol derivatives (7 and 8), and two new tetraprenyltoluquinone derivatives (9 and 10) were isolated from the brown alga Cystoseira crinita Duby together with four known tetraprenyltoluquinol derivatives (11-14). All structures were elucidated by employing spectroscopic techniques (NMR, MS, UV, and IR). Each compound was evaluated for its antioxidative properties in the TBARS and DPPH assay, and compounds 1, 2, 6, and 10-14 were additionally assessed in the TEAC and PCL assay. Hydroquinones were found to have powerful antioxidant activity. PMID:12880316

Fisch, Katja M; B鐬m, Volker; Wright, Anthony D; K霵ig, Gabriele M

2003-07-01

400

Novel meroditerpenes from the brown alga Cystoseira sp.  

PubMed

Five new meroditerpenes have been isolated from a brown alga of the genus Cystoseira collected around the Canary Islands. One, cystoseirone diacetate (3), possesses a new rearranged structure with an unusual ether linkage in the diterpene side chain. Its biogenetic origin was explained as derived from the oxidation of amentol chromane diacetate (2) and subsequent cyclization. Structures were determined through the interpretation of the spectral data and by means of chemical transformations. The relative stereochemistry was proposed on the basis of ROESY correlations. PMID:15043443

Navarro, Guillermo; Fern嫕dez, Jos J; Norte, Manuel

2004-03-01

401

PCD and autophagy in the unicellular green alga Micrasterias denticulata  

PubMed Central

Programmed cell death (PCD) plays a central role in normal plant development and is also induced by various biotic and abiotic stress factors. In the unicellular freshwater green alga Micrasterias denticulata morphological and biochemical hallmarks such as the appearance of autophagosomes, increased production of ROS and degradation of genomic DNA into small fragments (DNA laddering) indicate PCD. Our data not only demonstrate that Micrasterias is capable of performing PCD under salt stress, but also that it is triggered by the ionic and not osmotic component of salinity. Additionally, results from the present and previous studies suggest that different inducers may lead to different cell death pathways in one and the same organism.

Affenzeller, Matthias Josef; Darehshouri, Anza; Andosch, Ancuela; Lutz, Cornelius; Lutz-Meindl, Ursula

2010-01-01

402

CHLOROPLAST AND MITOCHONDRIAL DNA IN A BROWN ALGA EGREGIA MENZIESII  

PubMed Central

Chloroplasts and mitochondria of the brown alga Egregia menziesii were studied with the electron microscope. In both organelles, 15-25-A fibrils with DNA characteristics are found within areas of electron transparency. In each chloroplast there are two DNA-containing areas, one at each tip of the chloroplast. This localization, the shape and size of each DNA-containing area, and its close association with lamellae in a nondividing chloroplast are noted. One or occasionally two DNA-containing areas are found within the mitochondrion and they are compared with a similar structure in the chloroplast.

Bisalputra, T.; Bisalputra, A. A.

1967-01-01

403

Prospects of the Mass Cultivation of Algae as Bulk Fodder (Perspektyvy Masovoho Vyroshchuvannya Vodorostei Dlya Oderzhannya Kormovoii Masy).  

National Technical Information Service (NTIS)

Investigations on the laboratory and industrial cultivation of unicellular algae, Chlorella and Scenedesmus, for the production of bulk fodder have been carried out in the Soviet Union and abroad. Criteria for mass cultivation of algae are: the culture sh...

V. A. Kordyum

1969-01-01

404

Alternative Water Disinfection Schemes for Reduced Trihalomethane Formation. Volume 2. Algae as Precursors for Trihalomethanes in Chlorinated Drinking Water.  

National Technical Information Service (NTIS)

This study investigated three species of algae, Anabaena cylindrica, Scenedesmus quadricauda, and Pediastrum boryanum, with respect to their potential for the formation of THM when chlorinated. Algae were cultured and the cells (algal biomass) were separa...

C. A. Sorber K. F. Briley R. F. Williams

1984-01-01

405

Pyrolytic characteristics and kinetic studies of three kinds of red algae  

Microsoft Academic Search

Marine algae have great potential as a third generation biofuel feedstock. The pyrolytic and kinetic characteristics of three kinds of red algae (Pophyra yezoensis, Plocamium telfairiae Harv and Corallina pilulifera) were studied at heating rates of 10, 30 and 50蚓min?1 under an inert atmosphere. The most probable mechanism function and activation energy pre-exponential factors were calculated by the Popescu, FWO

Demao Li; Limei Chen; Xiaowen Zhang; Naihao Ye; Fuguo Xing

2011-01-01

406

Influence of Relative Humidity on AC Corona Discharge from Algae Attached on the Silicone Rubber  

NASA Astrophysics Data System (ADS)

To make clear the influence of algae growth at the surface of a polymer insulator in a practical transmission line, the characteristics of ac corona discharge from an aggregate algae particle were investigated. The aggregate algae particle was made of Protococcus viridis. Corona onset voltage from an aggregate algae particle was decreased as relative humidity increased. Under the condition of relatively higher relative humidity, luminous channel of corona discharge became more strongly and the number of corona pulses in the current waveform was increased. For an aggregate algae particle contaminated with sea salt including MgCl2, corona onset voltage decreased drastically at relative humidity above 40%. This property would result from deliquescence of MgCl2. Corona discharge was strongly affected by existence of MgCl2 in an aggregate algae particle. Surface resistance of algae attached to the surface of the silicone rubber sheet decreased in fourth figures for relative humidity from 20 to 90%. Therefore, the existence of algae on the polymer insulator inevitably affects the electric property and the surface property of the polymer insulator.

Sato, Daisuke; Hara, Yoshiaki; Kokufu, Morihide; Higashiyama, Yoshio

407

Biomass, species composition and diversity of epipelic algae in mire pools  

Microsoft Academic Search

The biomass, species composition and diversity of epipelic algae in two small pools of contrasting physicochemical characteristics in Miyatoko Mire were studied in 1992 (pool 3 =site B4 and pool 50 =site D2). A total of 93 species and 67 species of epipelic algae occurred at sites B4 and D2, respectively. Considerable differences were observed between the two sites in

Makoto M. Watanabe; Shigeki Mayama; Mikiya Hiroki; Hisayoshi Nozaki

2000-01-01

408

The Mediterranean red alga Asparagopsis: a source of compounds against Leishmania.  

PubMed

Crude extracts and column fractions from the red algae Asparagopsis taxiformis and A. armata from the Strait of Messina (Italy) were screened for the production of antimicrobial compounds. Extracts from both species revealed remarkable antiprotozoal activity against Leishmania, revealing such algae as a great source of natural antiprotozoal products. PMID:19841720

Genovese, Giuseppa; Tedone, Laura; Hamann, Mark T; Morabito, Marina

2009-08-11

409

The Mediterranean Red Alga Asparagopsis: A Source of Compounds against Leishmania  

PubMed Central

Crude extracts and column fractions from the red algae Asparagopsis taxiformis and A. armata from the Strait of Messina (Italy) were screened for the production of antimicrobial compounds. Extracts from both species revealed remarkable antiprotozoal activity against Leishmania, revealing such algae as a great source of natural antiprotozoal products.

Genovese, Giuseppa; Tedone, Laura; Hamann, Mark T.; Morabito, Marina

2009-01-01

410

Benthic algae as bioindicators of agricultural pollution in the streams and rivers of southern Qu嶵ec (Canada)  

Microsoft Academic Search

The objective of this study was to evaluate the effect of agricultural pollution on periphyton in streams and rivers of southern Qu嶵ec. We sampled benthic algae incubated from mid-July to mid-August on artificial substrates at 29 sites and analysed the variations in community structure and total community biomass. Diatom community structure as well as total benthic algae community were analysed.

Isabelle Lavoie; Warwick F. Vincent; Reinhard Pienitz; Jean Painchaud

2004-01-01

411

Distribution and relationships between selected chemical elements in green alga Enteromorpha sp. from the southern Baltic  

Microsoft Academic Search

The concentrations of heavy metals (Cd, Cu, Ni, Pb, Zn and Mn) and macroelements (K, Na, Ca and Mg) were determined in green alga Enteromorpha sp. from the coastal zone of the southern Baltic including Gulf of Gda?sk and Vistula Lagoon in 20002003. In order to estimate the degree of accumulation of each element by the green alga, concentration and

Rados?aw ?bikowski; Piotr Szefer; Adam Lata?a

2006-01-01

412

Artificial microfossils: experimental studies of permineralization of blue-green algae in silica.  

PubMed

A technique has been developed to artificially fossilize microscopic algae in crystalline silica under conditions of moderately elevated temperature and pressure. The technique is designed to simulate geochemical processes thought to have resulted in the preservation of organic microfossils in Precambrian bedded cherts. In degree of preservation and mineralogic setting, the artificially permineralized microorganisms are comparable to naturally occurring fossil algae. PMID:17806931

Oehler, J H; Schopf, J W

1971-12-17

413

Economic Feasibility of Commercial Algae Oil Production in the United States  

Microsoft Academic Search

A Monte Carlo simulation model was constructed to analyze the economic feasibility of growing algae as a renewable fuel source. Increasing growth rates, pond water depth, oil content, and facility size are important for ensuring the economic viability of a commercial algae facility.

Bart L. Fischer; James W. Richardson; Joe L. Outlaw; Marc S. Allison

2011-01-01

414

Plutonium in fish, algae, and sediments in the Barents, Petshora and Kara Seas  

Microsoft Academic Search

This work contributed to a joint research programme between the Finnish Centre for Radiation and Nuclear Safety and the Murmansk Marine Biological Institute in the Arctic. Radioanalyses for plutonium isotopes were performed on more than 50 sediment samples, 12 algae samples and 19 fish samples. Plutonium concentrations in algae and fish samples, including fish meat, bone and liver, were low

T. K. Ik鄣eimonen; K. Rissanen; D. G. Matishov; G. G. Matishov

1997-01-01

415

Nuclear DNA Content Estimates in Multicellular Green, Red and Brown Algae: Phylogenetic Considerations  

Microsoft Academic Search

? Background and Aims Multicellular eukaryotic algae are phylogenetically disparate. Nuclear DNA content estimates have been published for fewer than 1 % of the described species of Chlorophyta, Phaeophyta and Rhodophyta. The present investigation aims to summarize the state of our knowledge and to add substantially to our database of C-values for theses algae. ? Methods The DNA-localizing fluorochrome DAPI

DONALD F. KAPRAUN

2005-01-01

416

Defined Media for Growth and Gamete Production by the Green Alga, Oedogonium cardiacum1  

PubMed Central

Defined media consisting of inorganic salts and vitamin B12 are described for the male and female filaments of the green alga, Oedogonium cardiacum. These media provide for a maximal growth rate and for the induction of oogonia and antheridia under the prescribed conditions. The maximal amounts of growth, based on dry weight measurements, compare favorably with other green algae.

Hill, G. J. C.; Machlis, Leonard

1970-01-01

417

Invertebrate Grazer - Epiphytic Algae Interactions on Submerged Macrophytes in a Mesotrophic Turkish Lake  

Microsoft Academic Search

Invertebrate - epiphytic algae interaction in the periphyton of Potamogeton pectinatus L. and Potamogeton perfoliatus L. collected from the littoral of Lake ?znik was investigated between May 1993 - November 1994. A close relationship was observed between some invertebrates and algae in the periphyton. A decrease was observed in stalked and tubes diatom density whilst nematodes in Potamogeton perfoliatus periphyton

Meri Albay; Gler Aykulu

2002-01-01

418

Studies on the growth of some marine unicellular algae under different artificial light sources  

Microsoft Academic Search

Documented evidence of the suitability of various artificial light sources for the culture of unicellular algae is scarce. This paper reports the results of a comparison of the growth rates of 5 species of marine unicellular algae at various light intensities produced by an incandescent filament source or daylight fluorescent tubes. Under light saturating conditions the maximum growth rate achieved

F. O. Quraishi; C. P. Spencer

1971-01-01

419

Systematics of the marine microfilamentous green algae Uronema curvatum and Urospora microscopica (Chlorophyta)  

Microsoft Academic Search

The microfilamentous green alga Uronema curvatum is widely distributed along the western and eastern coasts of the north Atlantic Ocean where it typically grows on crustose red algae and on haptera of kelps in subtidal habitats. The placement of this marine species in a genus of freshwater Chlorophyceae had been questioned. Molecular phylogenetic analysis of nuclear-encoded small and large subunit

Frederik Leliaert; Jan Rueness; Christian Boedeker; Christine A. Maggs; Ellen Cocquyt; Heroen Verbruggen; Olivier De Clerck

2009-01-01

420

Defined Media for Growth and Gamete Production by the Green Alga, Oedogonium cardiacum.  

PubMed

Defined media consisting of inorganic salts and vitamin B(12) are described for the male and female filaments of the green alga, Oedogonium cardiacum. These media provide for a maximal growth rate and for the induction of oogonia and antheridia under the prescribed conditions. The maximal amounts of growth, based on dry weight measurements, compare favorably with other green algae. PMID:16657439

Hill, G J; Machlis, L

1970-08-01

421

Combined Nitrogen and Phosphorus Fertilization for Controlling the Toxigenic Alga Prymnesium parvum  

Microsoft Academic Search

The toxigenic alga Prymnesium parvum has caused significant fish kills in Texas reservoirs and fish hatchery ponds since 2001. Copper sulfate and ammonium sulfate can control P. parvum, but they provide short-term improvement and have undesirable side effects. Copper sulfate also kills desirable algae and invertebrates, and ammonium sulfate can be harmful to fish. Because dominance of the phytoplankton community

Gerald L. Kurten; Aaron Barkoh; Loraine T. Fries; Drew C. Begley

2007-01-01

422

Water Purification and Recovery of Fertilizer Materials by Blue Green Algae (Cyanobacteria). Final Report.  

National Technical Information Service (NTIS)

The object of this research project was to compare the water purification and recovery of fertilizer materials by blue green algae (Cyanobacteria) under thermal and non-thermal or ambient conditions. The thermal tests were conducted in a solar algae growt...

J. Bender

1983-01-01

423

Production and chlorophyll concentration of epipelic and epilithic algae in fertilized and nonfertilized subarctic lakes  

Microsoft Academic Search

The production and chlorophyll concentration of epipelic and epilithic algae was measured during four years (19721975) in two shallow, Swedish subarctic lakes. One lake (Lake Hymenjaure) was fertilized with phosphorus or a combination of phosphorus and nitrogen while the other (Lake Stugsj霵) served as a reference. The benthic algae in both lakes were dominated by Cyanophyceae of the same species

Susanna Bjiirk-Ramberg; Claes 囊ell

1985-01-01

424

Water purification and recovery of fertilizer materials by blue green algae (Cyanobacteria). Final report  

Microsoft Academic Search

The object of this research project was to compare the water purification and recovery of fertilizer materials by blue green algae (Cyanobacteria) under thermal and non-thermal or ambient conditions. The thermal tests were conducted in a solar algae growth tank, in which a solar heat exchanger provided thermal conditions of 60 C during daytime hours. 6 figures, 1 table.

2008-01-01

425

Brown algae species as biomonitors of Zn and Cd at Sepetiba Bay, Rio de Janeiro, Brazil  

Microsoft Academic Search

In order to contribute to monitoring heavy metal contamination of Sepetiba Bay, Rio de Janeiro, Brazil, long term evaluation of Zn and Cd concentration was performed in two brown algae species, Padina gymnospora and Sargassum stenophyllum. In relation to Sepetiba Bay macroalgae community, these species were the most abundant in substrate cover. The algae metal concentration variation from 1990 to

G. M. Amado Filho; L. R. Andrade; C. S. Karez; M. Farina; W. C. Pfeiffer

1999-01-01

426

Electron microscopy study of biosorbents from marine macro alga Durvillaea potatorum  

Microsoft Academic Search

Biosorbents derived from the biomass of marine algae have shown to have high uptake capacities for heavy metals and the internal structure has been generally assumed to be pseudo-homogenous. In this paper, the microstructures of biosorbents derived from Australian marine alga Durvillaeapotatorum were analysed using scanning electron microscopy. The structural components of the biosorbent resembled fiber-like cylinders. The internal structure

Qiming Yu; Pairat Kaewsarn; Loc Van Duong

2000-01-01

427

Selective production of glutamate by an immobilized marine blue-green alga, Synechococcus sp  

Microsoft Academic Search

Among 200 strains of marine bluegreen algae isolated from the coastal areas of Japan, the marine blue-green alga Synechococcus sp. NKBG 040607 excreted glutamate at the highest rate, 82.6% of total amino acids production being glutamate. Synechococcus sp. NKBG 40607 was immobilized in calcium alginate gel. Glutamate production by immobilized cells was double that of native cells. Maximal glutamate production

Tadashi Matsunaga; Noriyuki Nakamura; Naoko Tsuzaki; Hiroyuki Takeda

1988-01-01

428

Lack of avoidance of phenolic-rich brown algae by tropical herbivorous fishes  

Microsoft Academic Search

High levels of polyphloroglucinol phenolics in marine brown algae are usually interpreted as a defensive response to herbivory. However, tropical brown algae generally contain very low levels of phenolics, even though herbivory in many tropical systems (e.g. coral reefs) is intense. This apparent paradox would be explained if polyphenolics did not deter tropical herbivores, in which case selection by herbivores

P. D. Steinberg; K. Edyvane; R. de Nys; R. Birdsey; I. A. van Altena

1991-01-01

429

Effect of manganese and nickel on growth of selected algae in pH buffered medium  

Microsoft Academic Search

Algal species distribution has frequently been correlated with pH and metal concentrations in streams contaminated by acid mine drainage. To determine if pH or metal is more influential in algal distribution, laboratory experiments were performed using two species of a filamentous green alga (Ulothrix) common in streams receiving acid mine drainage. Algae were exposed in acute toxicity tests to buffered

Jeffrey M Rousch; Milton R Sommerfeld

1999-01-01

430

Limited Effects of Barley Straw on Algae and Zooplankton in a Midwestern Pond  

Microsoft Academic Search

Researchers in the United Kingdom have reported that barley straw can be used to control a variety of planktonic algae, as well as the filamentous alga Cladophora spp. This method appears to be cost-effective, user-friendly, and environmentally sound. If these results could be obtained in the United States, using barley straw would be a good alternative to using copper sulfate.

Joseph D. Boylan; Joseph E. Morris

2003-01-01

431

Application of toxic agents in the study of the ecological resistance of intertidal red algae  

Microsoft Academic Search

Biebl (1939a, b) has found that algae from various ecological groups show marked differences in their resistance to changes in the temperature of the surrounding sea water. He regards this temperature effect as an important factor influencing the distribution of different intertidal algae and points out that a change of only 2 C may prove critical with certain species. One

A. D. Boney; E. D. S. Corner

1959-01-01

432

X-ray diffraction study of mineral components in calcareous algae (Corallinaceae, Rhodophyta)  

Microsoft Academic Search

The mineral composition of nine species of red calcareous algae (Corallinaceae, Rhodophyta) collected in the Adriatic Sea in 1987 and 1988 was examined by X-ray powder diffraction (counter diffractometer, monochromatized CuKa radiation). In addition, a comparison between the calcareous algae from the north Adriatic (Rovinj area) and the central Adriatic (Kornati Islands) with regard to genus, species and environmental factors

D. Medakovi?; S. Popovi?; N. Zavodnik; B. Greta; M. Plazonic

1995-01-01

433

A Critical Test of Methods for Isolation of Viruses for Use in Control of Nuisance Algae.  

National Technical Information Service (NTIS)

Since blue green algae comprise one class of algal polluters, it was of interest to determine whether specific biological algicides, namely blue-green algae viruses (BGAV) are practical, specific algal control agents. The objects of this study were (a) to...

H. N. Guttman

1973-01-01

434

MONITORING CHLOROPHYLL-A AS A MEASURE OF ALGAE IN LAKE TEXOMA MARINAS  

EPA Science Inventory

Lake water quality in five marinas on Lake Texoma was determined over a two year period. Quality parameters were methyl tert-butyl ether, nitrate, some metals, fecal coliform and algae. Common blue-green algae can produce a toxin harmful to other aquatic organisms and humans. ...

435

Microbial to reef scale interactions between the reef-building coral Montastraea annularis and benthic algae.  

PubMed

Competition between reef-building corals and benthic algae is of key importance for reef dynamics. These interactions occur on many spatial scales, ranging from chemical to regional. Using microprobes, 16S rDNA pyrosequencing and underwater surveys, we examined the interactions between the reef-building coral Montastraea annularis and four types of benthic algae. The macroalgae Dictyota bartayresiana and Halimeda opuntia, as well as a mixed consortium of turf algae, caused hypoxia on the adjacent coral tissue. Turf algae were also associated with major shifts in the bacterial communities at the interaction zones, including more pathogens and virulence genes. In contrast to turf algae, interactions with crustose coralline algae (CCA) and M. annularis did not appear to be antagonistic at any scale. These zones were not hypoxic, the microbes were not pathogen-like and the abundance of coral-CCA interactions was positively correlated with per cent coral cover. We propose a model in which fleshy algae (i.e. some species of turf and fleshy macroalgae) alter benthic competition dynamics by stimulating bacterial respiration and promoting invasion of virulent bacteria on corals. This gives fleshy algae a competitive advantage over corals when human activities, such as overfishing and eutrophication, remove controls on algal abundance. Together, these results demonstrate the intricate connections and mechanisms that structure coral reefs. PMID:22090385

Barott, Katie L; Rodriguez-Mueller, Beltran; Youle, Merry; Marhaver, Kristen L; Vermeij, Mark J A; Smith, Jennifer E; Rohwer, Forest L

2011-11-16

436

Closed and continuous algae cultivation system for food production and gas exchange in CELSS  

NASA Astrophysics Data System (ADS)

In CELSS (Controlled Ecological Life Support System), utilization of photosynthetic algae is an effective means for obtaining food and oxygen at the same time. We have chosen Spirulina, a blue-green alga, and have studied possibilities of algae utilization. We have developed an advanced algae cultivation system, which is able to produce algae continuously in a closed condition. Major features of the new system are as follows. o (1)In order to maintain homogeneous culture conditions, the cultivator was designed so as to cause a swirl on medium circulation. (2)Oxygen gas separation and carbon dioxide supply are conducted by a newly designed membrane module. (3)Algae mass and medium are separated by a specially designed harvester. (4)Cultivation conditions, such as pH, temperature, algae growth rate, light intensity and quanlity of generated oxygen gas are controlled by a computer system and the data are automatically recorded. This equipment is a primary model for ground experiments in order to obtain some design data for space use. A feasibility of algae cultivation in a closed condition is discussed on the basis of data obtained by use of this new system.

Oguchi, Mitsuo; Otsubo, Koji; Nitta, Keiji; Shimada, Atsuhiro; Fujii, Shigeo; Koyano, Takashi; Miki, Keizaburo

437

Effectiveness and mechanism of potassium ferrate(VI) preoxidation for algae removal by coagulation.  

PubMed

Jar tests were conducted to evaluate the effectiveness of potassium ferrate preoxidation on algae removal by coagulation. Laboratory studies demonstrated that pretreatment with potassium ferrate obviously enhanced the algae removal by coagulation with alum [Al2(SO4)3 . 18H2O]. Algae removal efficiency increased remarkably when the water was pretreated with ferrate. A very short time of preoxidation was enough to achieve substantial algae removal efficiency, and the effectiveness was further increased at a prolonged pretreatment time. Pretreatment with ferrate resulted in a reduction of alum dosage required to cause an efficient coagulation for algae removal. The obvious impact of cell architecture by potassium ferrate was found through scanning electron microscopy. Upon oxidation with ferrate. the cells were inactivated and some intracellular and extracelluar components were released into the water, which may be helpful to the coagulation by their bridging effect. Efficient removal of algae by potassium ferrate preoxidation is believed to be a consequence of several process mechanisms. Ferrate preoxidation inactivated algae, induced the formation of coagulant aid, which are the cellular components secreted by algal cells. The coagulation was also improved by increasing particle concentration in water, because of the formation of the intermediate forms of precipitant iron species during preoxidation. In addition, it was also observed that ferrate preoxidation caused algae agglomerate formation before the addition of coagulant, the subsequent application of alum resulted in further coagulation. PMID:11848357

Ma, Jun; Liu, Wei

2002-02-01

438

Comparative study of CV active contour model and subdivision for micro algae image segmentation  

Microsoft Academic Search

Mass of micro algae propagated may produce harmful effects on marine ecological environment and fishery resources. The rapid and accurate identification and classification for micro algae is one of the important research issues in fisheries resource. In this paper, the comparative study of two segmentation methods, which are C-V active contour model based on partial differential equation and the 4-point

Lime Zhang; Bo Wang; Zhongxuan Luo; Jielin Zhang

2011-01-01

439

The Nature and Distribution of Carotenoids in some Blue-Green Algae  

Microsoft Academic Search

SUMMARY : Seven blue-green algae, Anabaena cylindrica, A. variabilis, Coccochloris elabens, Cylindrospermum sp., Mastigocladus laminosus, Microcoleus vaginatus and Nostoc sp., synthesize the same three major carotenoids : ,&carotene, echinenone and myxoxanthophyll; zeaxanthin is present in small amounts. Lutein could not be detected. \\/3-Carotene represents between 30 and 60% of the total carotenoids present. The carotenoid distribution in blue-green algae and

T. W. Goodwin

1957-01-01

440

A review of the nutritional effects of algae in marine fish larvae  

Microsoft Academic Search

In the first-feeding of larval, turbot (Scophthalmus maximus) and halibut (Hippoglossus hippoglossus), microalgae are used in the production of rotifers (Brachionus plicatilis) in order to transfer essential nutrients from the algae to the live food. In addition, the algae may be given directly to the larvae along with the live food. In this circumstance they act both as food for

Kjell Inge Reitan; Jose R. Rainuzzo; Gunvor 喭e; Yngvar Olsen

1997-01-01

441

Food Preference of Fresh-Water Invertebrates - Comparing Fresh and Decomposed Angiosperm and a Filamentous Alga  

Microsoft Academic Search

1. Fresh and decomposed Mougeotia sp. (a filamentous green alga) and Elodea nuttallii (a vascular plant) were offered as food to three species of aquatic macroinvertebrates (Lymnnea peregra, Asellus meridianus and Endochironomus albipennis) to test: (i) if filamentous algae are preferred to aquatic higher plants (hereafter, called 'macrophytes') and (ii), as is known for higher plants, if decomposition also results

R. Kornijow; R. D. Gulati; T. Ozimek

1995-01-01

442

Resource demand implications for US algae biofuels production scale-up  

Microsoft Academic Search

Photosynthetic microalgae with the potential for high biomass and oil productivities have long been viewed as a promising class of feedstock for biofuels to displace petroleum-based transportation fuels. Algae offer the additional benefits of potentially being produced without using high-value arable land and fresh water, thereby reducing the competition for those resources between expanding biofuels production and conventional agriculture. Algae

Ron Pate; Geoff Klise; Ben Wu

2011-01-01

443

Responses of stream algae to grazing minnows and nutrients: a field test for interactions  

Microsoft Academic Search

Previous studies have shown that an algivorous grazing minnow (Campostoma anomalum) is the major herbivore in Brier Creek, a hardwater stream in south central Oklahoma. In summer and autumn schools of Campostoma virtually eliminate algae from substrate surfaces in deeper areas of some pools. The pool-to-pool distributions of algae and Campostoma reported for this stream could occur if nutrient limitation

A. J. Stewart

1987-01-01

444

Flora and fauna associated with the introduced red alga Gracilaria vermiculophylla  

Microsoft Academic Search

This paper presents the first detailed study of the spread of the introduced marine red alga Gracilaria vermiculophylla on the west coast of Sweden, and of the fauna and flora associated with this alga in Scandinavia and the western mid-Atlantic. G. vermiculophylla was discovered in the archipelago of G飆eborg, Sweden, in the summer of 2003, and in 2005 its distribution

Cecilia D. Nyberg; Mads S. Thomsen; Inger Wallentinus

2009-01-01

445

The Ectocarpus genome and the independent evolution of multicellularity in brown algae  

Microsoft Academic Search

Brown algae (Phaeophyceae) are complex photosynthetic organisms with a very different evolutionary history to green plants, to which they are only distantly related. These seaweeds are the dominant species in rocky coastal ecosystems and they exhibit many interesting adaptations to these, often harsh, environments. Brown algae are also one of only a small number of eukaryotic lineages that have evolved

J. Mark Cock; Lieven Sterck; Pierre Rouz; Delphine Scornet; Grigoris Amoutzias; Veronique Anthouard; Fran蔞is Artiguenave; Jean-Marc Aury; Jonathan H. Badger; Bank Beszteri; Kenny Billiau; Eric Bonnet; John H. Bothwell; Chris Bowler; Catherine Boyen; Colin Brownlee; Carl J. Carrano; B幯嶮icte Charrier; Ga Youn Cho; Susana M. Coelho; Jonas Coll幯; Erwan Corre; Corinne da Silva; Ludovic Delage; Nicolas Delaroque; Simon M. Dittami; Sylvie Doulbeau; Marek Elias; Garry Farnham; Claire M. M. Gachon; Bernhard Gschloessl; Svenja Heesch; Kamel Jabbari; Claire Jubin; Hiroshi Kawai; Kei Kimura; Bernard Kloareg; Frithjof C. Kpper; Daniel Lang; Aude Le Bail; Catherine Leblanc; Patrice Lerouge; Martin Lohr; Pascal J. Lopez; Cindy Martens; Florian Maumus; Gurvan Michel; Diego Miranda-Saavedra; Julia Morales; Herv Moreau; Taizo Motomura; Chikako Nagasato; Carolyn A. Napoli; David R. Nelson; Pi Nyvall-Coll幯; Akira F. Peters; Cyril Pommier; Philippe Potin; Julie Poulain; Hadi Quesneville; Betsy Read; Andr廥 Ritter; Sylvie Rousvoal; Manoj Samanta; Gaelle Samson; Declan C. Schroeder; B嶧trice S嶲urens; Martina Strittmatter; Thierry Tonon; James W. Tregear; Klaus Valentin; Peter von Dassow; Takahiro Yamagishi; Yves van de Peer; Patrick Wincker

2010-01-01

446

Biotechnological potential of immobilized algae for wastewater N, P and metal removal: A review  

Microsoft Academic Search

This presentation comprises a review on the use of immobilized algae for wastewater nitrogen, phosphorus and metal removal purposes. Details of the use of immobilized algae, the techniques of immobilization and the effects of immobilization on cell function are included. Particularly relevant in their use for heavy metal removal from wastewaters; upon enriching the biomass in metal, can be recoverd,

Nirupama Mallick

2002-01-01

447

Travel-related chronic hemorrhagic leg ulcer infection by Shewanella algae.  

PubMed

Shewanella algae is an emerging seawater-associated bacterium. In immunocompromised patients, infections may result in bacteremia, osteomyelitis, and necrotizing fasciitis. Our patient, suffering from autoimmune vasculitis and myasthenia gravis, developed typical hemorrhagic bullae and leg ulcers because of S algae. She was treated efficiently with a combination of ciprofloxacin and piperacillin. PMID:23809079

Wagner, Nicola; Otto, Lisa; Podda, Maurizio; Schmitt, York; Tappe, Dennis

2013-05-22

448

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

Microsoft Academic Search

In this study, we examined genetic variation in resistance and tolerance to fouling organisms in the brown alga Fucus vesiculosus. We first grew 30 algal genotypes in the field, where we allowed fouling organisms to colonise the genotypes at natural levels.\\u000a We then conducted a manipulative experiment, where we grew 20 genotypes of algae in aquaria with or without fouling

Tuija Honkanen; Veijo Jormalainen

2005-01-01

449

Enzymes of the Heme Biosynthetic Pathway in the Nonphotosynthetic Alga Polytomella sp  

Microsoft Academic Search

Heme biosynthesis involves a number of enzymatic steps which in eukaryotes take place in different cell compartments. Enzyme compartmentalization differs between photosynthetic and nonphotosynthetic eu- karyotes. Here we investigated the structures and subcellular localizations of three enzymes involved in the heme pathway in Polytomella sp., a colorless alga evolutionarily related to the green alga Chlamydomonas reinhardtii. Functional complementation of Escherichia

Ariane Atteia; Robert van Lis; Samuel I. Beale

2005-01-01

450

Trace metals with seasonal considerations in coastal algae and molluscs from Beirut, Lebanon  

Microsoft Academic Search

Twelve species of intertidal algae and molluscs from Ras Beirut, Lebanon have been investigated for their heavy metal content. Atomic absorption spectrophotometric analysis showed that the algae and molluscs concentrated similar levels of most metals. However, of the twelve organisms, Brachydontes variabilis had the highest copper, Patella coerulea and Colpomenia sinuosa had the highest iron, and Pinctada radiata had the

J. G. Shiber

1980-01-01

451

FRESHWATER ALGAE OF RAE LAKES BASIN, KINGS CANYON NATIONAL PARK (CALIFORNIA)  

EPA Science Inventory

This report illustrates and characterizes algae (exclusive of diatoms) found in Kings Canyon National Park, California and describes their distribution among the Rae Lakes within. It is the first taxonomic study of the freshwater algae for the southern Sierra Nevada and the most ...

452

The Effects of Nutrient Enrichment and Herbivore Abundance on the Ability of Turf Algae to Overgrow Coral in the Caribbean  

PubMed Central

Turf algae are multispecies communities of small marine macrophytes that are becoming a dominant component of coral reef communities around the world. To assess the impact of turf algae on corals, we investigated the effects of increased nutrients (eutrophication) on the interaction between the Caribbean coral Montastraea annularis and turf algae at their growth boundary. We also assessed whether herbivores are capable of reducing the abundance of turf algae at coral-algae boundaries. We found that turf algae cause visible (overgrowth) and invisible negative effects (reduced fitness) on neighbouring corals. Corals can overgrow neighbouring turf algae very slowly (at a rate of 0.12 mm 3 wk?1) at ambient nutrient concentrations, but turf algae overgrew corals (at a rate of 0.34 mm 3 wk?1) when nutrients were experimentally increased. Exclusion of herbivores had no measurable effect on the rate turf algae overgrew corals. We also used PAM fluorometry (a common approach for measuring of a colony's fitness) to detect the effects of turf algae on the photophysiology of neighboring corals. Turf algae always reduced the effective photochemical efficiency of neighbouring corals, regardless of nutrient and/or herbivore conditions. The findings that herbivores are not capable of controlling the abundance of turf algae and that nutrient enrichment gives turf algae an overall competitive advantage over corals together have serious implications for the health of Caribbean coral reef systems. At ambient nutrient levels, traditional conservation measures aimed at reversing coral-to-algae phase shifts by reducing algal abundance (i.e., increasing herbivore populations by establishing Marine Protected Areas or tightening fishing regulations) will not necessarily reduce the negative impact of turf algae on local coral communities. Because turf algae have become the most abundant benthic group on Cura蓷o (and likely elsewhere in the Caribbean), new conservation strategies are required to mitigate their negative impact on coral communities.

Vermeij, Mark J. A.; van Moorselaar, Imke; Engelhard, Sarah; Hornlein, Christine; Vonk, Sophie M.; Visser, Petra M.

2010-01-01

453

Cultivation of nitrogen-fixing blue-green algae on ammonia-depleted effluents from sewage oxidation ponds  

Microsoft Academic Search

The data presented represent an initial, limited attempt on a small scale to cultivate nitrogen-fixing blue-green algae on both chemically defined media and low nitrogen sewage pond effluents. The rates of blue-green algal biomass production were low compared to those of green algae. Nevertheless, it appears that cultivation of nitrogen-fixing blue-green algae is possible on sewage effluents where these algae

J. C. Weissman; D. M. Eisenberg; J. R. Benemann

1978-01-01

454

[Hydrocarbons of the spiruline algae: nature, metabolism of heptadecane by rats and swine].  

PubMed

Hydrocarbons represent about half of the insaponifiable fraction of spirulina algae (0.1 to 0.3 p. 100 of the dry alga); n-heptadecane is the major component (65 p. 100). The retention of this paraffin has been measured in animals receiving these algae as the main or partial protein source. Rats fed with a diet containing 280 ppm n-heptadecane (25 p. 100 alga meal) from weaning show an accumulation of this hydrocarbon in the carcass the retention levels off after 4 months and seems related to the lipid content; preferential fixation occurs in adipose tissue. Sows receiving a diet with 52 ppm heptadecane (5p. 100 alga meal) during growth, pregnancy and lactation retain comparatively much less hydrocarbon; nevertheless n-heptadecane is excreted in the milk. PMID:824998

Tulliez, J; Bories, G; Boudene, C; Fevrier, C

1975-01-01

455

The green alga Dicytosphaeria ocellata and its organic extracts alter natural bacterial biofilm communities.  

PubMed

Surfaces immersed in the marine environment are under intense fouling pressure by a number of invertebrates and algae. The regulation of this fouling can often be attributed to the bacterial biofilm that quickly develops on the surface of any available substratum in the ocean. The bacterial community composition on the surface of the green alga Dictyosphaeria ocellata was investigated and compared to those found on two other green algae, Batophora oerstedii and Cladophoropsis macromeres, and on a reference surface from three sites along the Florida Keys. Although the bacterial community composition of D. ocellata was not consistent across the sites, it was significantly different from the other algae and the reference surface at two of the three sites tested. Methanol extracts of D. ocellata significantly affected the abundance of bacteria and composition of the bacterial community on Phytagel plates when compared to solvent controls, suggesting that the alga regulates the bacterial community by producing active metabolites. PMID:21512919

Sneed, Jennifer M; Pohnert, Georg

2011-04-01

456

Thermal preparation of highly porous calcium phosphate bone filler derived from marine algae.  

PubMed

A sustainable marine-derived bioceramic with a unique porous structure has been developed for hard tissue repair. The conversion of alga was achieved through a novel technique, involving well controlled thermal processing followed by low pressure-temperature hydrothermal synthesis. In its preparation, a heat treatment step was required to remove the organic compounds from the algae, which reinforces the mineralised matrices. Its removal is necessary to prevent issue such as immune biocompatibility and ensure phase purity of the resultant biomaterial. This paper investigates the hydrothermal technique used for the transformation of mineralised red algae to hydroxyapatite that preserves the algae's unique structure. It specifically focuses on the effects of heat treatment on the morphology of the algae, TGA, SEM and hot stage XRD to quantity the changes. PMID:20333540

Walsh, P J; Walker, G M; Maggs, C A; Buchanan, F J

2010-03-24

457

[Food value of the spiruline algae to man].  

PubMed

The acceptability of various culinary products based on the algae spirulina was tested by questionaire: formulas rich in proteins, soups, omelets, desserts. Spirulina are little appreciated in France due to offensive color, smell and taste. Tomato and chocolate are the most acceptable flavors. Lyophilisation is preferable to atomisation, and discoloration using alcohol is preferable to the acetone method. The hydrolysate obtained, having neither the smell nor the taste of algae, is excellent. Nitrogen, sodium and potassium balances were recorded in 5 undernourished subjects fed via a gastric tube. The spirulina provided respectively 15 p. 100 (1 subject), 30 p. 100 (2 subjects), and 50 p. 100 (2 subjects) of the protein ration. There were no intestinal problems. The spirulina did not modify the investigated balances. However, faecal nitrogen increased to 2.08 g (compared to control period values, 1.33 g and 1.51 g). The various coefficients: digestibility, nitrogen retention and protein utilization did not vary. In man as in animals, nitrogen retention is satisfactory, but digestibility is diminished. Uric acid did not vary in the urine, but serum values increased slightly. Ingestion of spirulina in small doses even over a long period should be tolerable in the normal subject. PMID:824995

Sautier, C; Tremolieres, J

1975-01-01

458

Antiprotozoal, antimycobacterial and cytotoxic potential of some british green algae.  

PubMed

In the continuation of our search for natural sources for antiprotozoal and antitubercular molecules, we have screened the crude extracts of four green marine algae (Cladophora rupestris, Codium fragile ssp. tomentosoides, Ulva intestinalis and Ulva lactuca) collected from the Dorset area of England. Trypanosoma brucei rhodesiense, Trypanosoma cruzi, Leishmania donovani and Mycobacterium tuberculosis were used as test organisms in the in vitro assays. The selective toxicity of the extracts was also determined toward mammalian skeletal myoblast (L6) cells. The crude seaweed extracts had no activity against M. tuberculosis, but showed antiprotozoal activity against at least two protozoan species. All algal extracts were active against T. brucei rhodesiense, with C. rupestris being the most potent one (IC(50) value 3.7 microg/ml), whilst only C. rupestris and U. lactuca had moderate trypanocidal activity against T. cruzi (IC(50) values 80.8 and 34.9 microg/ml). Again, all four extracts showed leishmanicidal activity with IC(50) values ranging between 12.0 and 20.2 microg/ml. None of the extracts showed cytotoxicity toward L6 cells, indicating that their antiprotozoal activity is specific. This is the first study reporting antiprotozoal and antimycobacterial activity of British marine algae. PMID:19960429

Spavieri, Jasmine; Kaiser, Marcel; Casey, Rosalyn; Hingley-Wilson, Suzie; Lalvani, Ajit; Blunden, Gerald; Tasdemir, Deniz

2010-07-01

459

Photosynthetic hydrogen and oxygen production by green algae  

SciTech Connect

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. From a scientific and technical point of view, current research is focused on optimizing net thermodynamic conversion efficiencies represented by the Gibbs Free Energy of molecular hydrogen. The key research questions of maximizing hydrogen and oxygen production by light-activated water splitting in green algae are (1) removing the oxygen sensitivity of algal hydrogenases; (2) linearizing the light saturation curves of photosynthesis throughout the entire range of terrestrial solar irradiance--including the role of bicarbonate and carbon dioxide in optimization of photosynthetic electron transport and (3) the minimum number of light reactions that are required to split water to elemental hydrogen and oxygen. Each of these research topics is being actively addressed by the photobiological hydrogen research community.

Greenbaum, E.; Lee, J.W.

1997-12-31

460

Photosynthetic Hydrogen and Oxygen Production by Green Algae  

SciTech Connect

Photosynthesis research at Oak Ridge National Laboratory is focused on hydrogen and oxygen production by green algae in the context of its potential as a renewable fuel and chemical feed stock. 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. From a scientific and technical point of view, current research is focused on optimizing net thermodynamic conversion efficiencies represented by the Gibbs Free Energy of molecular hydrogen. The key research questions of maximizing hydrogen and oxygen production by light-activated water splitting in green algae are: (1) removing the oxygen sensitivity of algal hydrogenases; (2) linearizing the light saturation curves of hotosynthesis throughout the entire range of terrestrial solar irradiance-including the role of bicarbonate and carbon dioxide in optimization of photosynthetic electron transpor;t and (3) constructing real-world bioreactors, including the generation of hydrogen and oxygen against workable back pressures of the photoproduced gases.

Greenbaum, E.; Lee, J.W.

1999-08-22

461

A novel obligate cultivation mutualism between damselfish and Polysiphonia algae.  

PubMed

In cultivation mutualisms, farming animals prepare fields for cultivars, enhance their growth and harvest them. For example, in terrestrial ecosystems, plant-herbivore cultivation mutualisms arose between humans and their crops only relatively recently. We discovered an obligate cultivation mutualism between a damselfish and an alga in a coral reef ecosystem. The damselfish, Stegastes nigricans, manages algal farms through territorial defence against the invading grazers and through weeding of unpalatable algae. As a result, the algal farms of S. nigricans are dominated by one species, Polysiphonia sp. We performed an exhaustive survey of algal assemblages inside and outside the territories of five damselfish species around the Ryukyu Islands, Japan, using molecular and morphological characteristics. Polysiphonia sp. 1 grew exclusively inside the farms of S. nigricans, and never elsewhere. Since only Polysiphonia sp. 1 is harvested and consumed by the damselfish as a staple food, this interdependent relationship is an obligate cultivation mutualism. This is the first record of an obligate plant-herbivore cultivation mutualism in a marine ecosystem. Our data also suggest that three other Polysiphonia species are facultatively mutual with, commensal with, or parasitic on other damselfish species. PMID:17148297

Hata, Hiroki; Kato, Makoto

2006-12-22

462

Indefatigable: an erect coralline alga is highly resistant to fatigue.  

PubMed

Intertidal organisms are subjected to intense hydrodynamic forces as waves break on the shore. These repeated insults can cause a plant or animal's structural materials to fatigue and fail, even though no single force would be sufficient to break the organism. Indeed, the survivorship and maximum size of at least one species of seaweed is set by the accumulated effects of small forces rather than the catastrophic imposition of a single lethal force. One might suppose that fatigue would be especially potent in articulated coralline algae, in which the strain of the entire structure is concentrated in localized joints, the genicula. However, previous studies of joint morphology suggest an alternative hypothesis. Each geniculum is composed of a single tier of cells, which are attached at their ends to the calcified segments of the plant (the intergenicula) but have minimal connection to each other along their lengths. This lack of neighborly attachment potentially allows the weak interfaces between cells to act as 'crack stoppers', inhibiting the growth of fatigue cracks. We tested this possibility by repeatedly loading fronds of Calliarthron cheilosporioides, a coralline alga common on wave-washed shores in California. When repeatedly loaded to 50-80% of its breaking strength, C. cheilosporioides commonly survives more than a million stress cycles, with a record of 51 million. We show how this extraordinary fatigue resistance interacts with the distribution of wave-induced water velocities to set the limits to size in this species. PMID:24068348

Denny, Mark; Mach, Katharine; Tepler, Sarah; Martone, Patrick

2013-10-15

463

Feeding by coral reef mesograzers: algae or cyanobacteria?  

NASA Astrophysics Data System (ADS)

Marine studies on herbivory have addressed the role of algae as food and shelter for small consumers, but the potential of benthic cyanobacteria to play similar roles is largely unknown. Here, feeding preferences were measured for eight invertebrate consumers from Guam, offered four common macroalgae and two cyanobacteria. The survivorship of another consumer raised on either macroalgae or cyanobacteria was also assessed. From the choices offered, the sacoglossans Elysia rufescens and E. ornata consumed the green macroalga Bryopsis pennata. The crab Menaethius monoceros preferred the red alga Acanthophora spicifera. The amphipods Parhyale hawaiensis and Cymadusa imbroglio consumed macroalgae and cyanobacteria in equivalent amounts, with C. imbroglio showing less selectivity among diets. In contrast to these patterns, in these assays the gastropods Stylocheilus striatus, Haminoea cymbalum, H. ovalis, and Haminoea sp. fed exclusively, or survived only, on cyanobacteria. Preferences for different cyanobacteria varied. Field surveys of cyanobacteria-associated species yielded 34 different invertebrate taxa and suggested different degrees of specificity in these associations. Tropical mesograzers exploit considerably different food resources, with some species adapted to consume cyanobacterial mats. Benthic cyanobacteria may play important roles as food and shelter for marine consumers and may indirectly influence local biodiversity through their associated fauna.

Cruz-Rivera, Edwin; Paul, Valerie J.

2006-11-01

464

Shotgun proteomic analysis of the unicellular alga Ostreococcus tauri.  

PubMed

Ostreococcus tauri is a unicellular green alga and amongst the smallest and simplest free-living eukaryotes. The O. tauri genome sequence was determined in 2006. Molecular, physiological and taxonomic data that has been generated since then highlight its potential as a simple model species for algae and plants. However, its proteome remains largely unexplored. This paper describes the global proteomic study of O. tauri, using mass spectrometry-based approaches: phosphopeptide enrichment, cellular fractionation, label-free quantification and (15)N metabolic labeling. The O. tauri proteome was analyzed under the following conditions: sampling at different times during the circadian cycle, after 24h of illumination, after 24h of darkness and under various nitrogen source supply levels. Cell cycle related proteins such as dynamin and kinesin were significantly up-regulated during the daylight-to-darkness transition. This is reflected by their higher intensity at ZT13 and this transition phase coincides with the end of mitosis. Proteins involved in several metabolic mechanisms were found to be up-regulated under low nitrogen conditions, including carbon storage pathways, glycolysis, phosphate transport, and the synthesis of inorganic polyphosphates. Ostreococcus tauri responds to low nitrogen conditions by reducing its nitrogen assimilation machinery which suggests an atypical adaptation mechanism for coping with a nutrient-limited environment. PMID:21635980

Le Bihan, Thierry; Martin, Sarah F; Chirnside, Eliane S; van Ooijen, Gerben; Barrios-Llerena, Martin E; O'Neill, John S; Shliaha, Pavel V; Kerr, Lorraine E; Millar, Andrew J

2011-05-24

465

Solar-driven hydrogen production in green algae.  

PubMed

The twin problems of energy security and global warming make hydrogen an attractive alternative to traditional fossil fuels with its combustion resulting only in the release of water vapor. Biological hydrogen production represents a renewable source of the gas and can be performed by a diverse range of microorganisms from strict anaerobic bacteria to eukaryotic green algae. Compared to conventional methods for generating H(2), biological systems can operate at ambient temperatures and pressures without the need for rare metals and could potentially be coupled to a variety of biotechnological processes ranging from desalination and waste water treatment to pharmaceutical production. Photobiological hydrogen production by microalgae is particularly attractive as the main inputs for the process (water and solar energy) are plentiful. This chapter focuses on recent developments in solar-driven H(2) production in green algae with emphasis on the model organism Chlamydomonas reinhardtii. We review the current methods used to achieve sustained H(2) evolution and discuss possible approaches to improve H(2) yields, including the optimization of culturing conditions, reducing light-harvesting antennae and targeting auxiliary electron transport and fermentative pathways that compete with the hydrogenase for reductant. Finally, industrial scale-up is discussed in the context of photobioreactor design and the future prospects of the field are considered within the broader context of a biorefinery concept. PMID:21807246

Burgess, Steven J; Tamburic, Bojan; Zemichael, Fessehaye; Hellgardt, Klaus; Nixon, Peter J

2011-01-01

466

Endolithic algae: an alternative source of photoassimilates during coral bleaching.  

PubMed

Recent reports of worldwide coral bleaching events leading to devastating coral mortality have caused alarm among scientists and resource managers. Differential survival of coral species through bleaching events has been widely documented. We suggest that among the possible factors contributing to survival of coral species during such events are endolithic algae harboured in their skeleton, providing an alternative source of energy. We studied the dynamics of photosynthetic pigment concentrations and biomass of endoliths in the skeleton of the encrusting coral Oculina patagonica throughout a bleaching event. During repeated summer bleaching events these endolithic algae receive increased photosynthetically active radiation, increase markedly in biomass, and produce increasing amounts of photoassimilates, which are translocated to the coral. Chlorophyll concentrations and biomass of endoliths were 4.6 +/- 1.57 and 1570 +/- 427 microg cm(-2) respectively, in skeletons of relatively healthy colonies (0-40% bleaching) but up to 14.8 +/- 2.5 and 4036 +/- 764 microg cm(-2) endolith chlorophyll and biomass respectively, in skeletons of bleached colonies (greater than 40% bleaching). The translocation dynamics of (14)C-labelled photoassimilates from the endoliths to bleached coral tissue showed significantly higher 14C activity of the endoliths harboured within the skeletons of bleached corals than that of the endoliths in non-bleached corals. This alternative source of energy may be vital for the survivorship of O. patagonica, allowing gradual recruitment of zooxanthellae and subsequent recovery during the following winter. PMID:12065035

Fine, Maoz; Loya, Yossi

2002-06-22

467

Unearthing the molecular phylodiversity of desert soil green algae (Chlorophyta).  

PubMed

Deserts are not usually considered biodiversity hotspots, but desert microbiotic crust communities exhibit a rich diversity of both eukaryotic and prokaryotic life forms. Like many communities dominated by microscopic organisms, they defy characterization by traditional species-counting approaches to assessing biodiversity. Here we use exclusive molecular phylodiversity (E) to quantify the amount of evolutionary divergence unique to desert-dwelling green algae (Chlorophyta) in microbiotic crust communities. Given a phylogenetic tree with branch lengths expressed in units of expected substitutions per site, E is the total length of all tree segments representing exclusively desert lineages. Using MCMC to integrate over tree topologies and branch lengths provides 95% Bayesian credible intervals for phylodiversity measures. We found substantial exclusive molecular phylodiversity based on 18S rDNA data, showing that desert lineages are distantly related to their nearest aquatic relatives. Our results challenge conventional wisdom, which holds that there was a single origin of terrestrial green plants and that green algae are merely incidental visitors rather than indigenous components of desert communities. We identify examples of lineage diversification within deserts and at least 12 separate transitions from aquatic to terrestrial life apart from the most celebrated transition leading to the embryophyte land plants. [Bayesian phylogenetics; biodiversity; exclusive molecular phylodiversity; microbiotic crusts.]. PMID:16338765

Lewis, Louise A; Lewis, Paul O

2005-12-01

468

Mass culture of algae using carbon dioxide from stack gases  

SciTech Connect

Algae are capable of converting CO{sub 2} into organic carbon via photosynthesis, and the efficiency with which this conversion is elected in dense algal cultures exceeds the photosynthetic of any terrestrial crop. It therefore seems reasonable to ask whether dense algal cultures could be used to strip all or part of the CO{sub 2} from power plant stack gases. A system designed to accomplish this task would require dissolving the CO{sub 2} from the stack gases in water and then growing the algae in the carbonated water. One of the principal factors limiting the practical application of this technology is the amount of land area which must be devoted to the collection of solar energy in order to effect the conversion of CO{sub 2} into organic matter. Collection of sunlight over an area of roughly 100 km{sup 2} (38.6 mi{sup 2}) would be required to convert all the CO{sub 2} from a typical 500 MW power plant into organic matter. The goal of this project was to provide information needed to determine whether such a system would be a practical way to control Co{sub 2} emissions from power plants. 23 refs., 18 figs., 15 tabs.

Laws, E. (Hawaii Univ., Honolulu, HI (USA). Office of Research Administration)

1990-10-01

469

Biotransformation of arsenic by a Yellowstone thermoacidophilic eukaryotic alga  

PubMed Central

Arsenic is the most common toxic substance in the environment, ranking first on the Superfund list of hazardous substances. It is introduced primarily from geochemical sources and is acted on biologically, creating an arsenic biogeocycle. Geothermal environments are known for their elevated arsenic content and thus provide an excellent setting in which to study microbial redox transformations of arsenic. To date, most studies of microbial communities in geothermal environments have focused on Bacteria and Archaea, with little attention to eukaryotic microorganisms. Here, we show the potential of an extremophilic eukaryotic alga of the order Cyanidiales to influence arsenic cycling at elevated temperatures. Cyanidioschyzon sp. isolate 5508 oxidized arsenite [As(III)] to arsenate [As(V)], reduced As(V) to As(III), and methylated As(III) to form trimethylarsine oxide (TMAO) and dimethylarsenate [DMAs(V)]. Two arsenic methyltransferase genes, CmarsM7 and CmarsM8, were cloned from this organism and demonstrated to confer resistance to As(III) in an arsenite hypersensitive strain of Escherichia coli. The 2 recombinant CmArsMs were purified and shown to transform As(III) into monomethylarsenite, DMAs(V), TMAO, and trimethylarsine gas, with a Topt of 6070 蚓. These studies illustrate the importance of eukaryotic microorganisms to the biogeochemical cycling of arsenic in geothermal systems, offer a molecular explanation for how these algae tolerate arsenic in their environment, and provide the characterization of algal methyltransferases.

Qin, Jie; Lehr, Corinne R.; Yuan, Chungang; Le, X. Chris; McDermott, Timothy R.; Rosen, Barry P.

2009-01-01

470

Hidden biodiversity of the extremophilic Cyanidiales red algae.  

PubMed

The Cyanidiales is a group of asexual, unicellular red algae, which thrive in acidic and high temperature conditions around hot springs. These unicellular taxa have a relatively simple morphology and are currently classified into three genera, Cyanidium, Cyanidioschyzon and Galdieria. Little is known, however, about the biodiversity of Cyanidiales, their population structure and their phylogenetic relationships. Here we used a taxonomically broadly sampled three-gene data set of plastid sequences to infer a robust phylogenetic framework for the Cyanidiales. The phylogenetic analyses support the existence of at least four distinct Cyanidiales lineages: the Galdieria spp. lineage (excluding Galdieria maxima), the Cyanidium caldarium lineage, a novel monophyletic lineage of mesophilic Cyanidium spp. and the Cyanidioschyzon merolae plus Galdieria maxima lineage. Our analyses do not support the notion of a mesophilic ancestry of the Cyanidiales and suggest that these algae were ancestrally thermo-acidotolerant. We also used environmental polymerase chain reaction (PCR) for the rbcL gene to sample Cyanidiales biodiversity at five ecologically distinct sites at Pisciarelli in the Phlegrean Fields in Italy. This analysis showed a high level of sequence divergence among Cyanidiales species and the partitioning of taxa based on environmental conditions. Our research revealed an unexpected level of genetic diversity among Cyanidiales that revises current thinking about the phylogeny and biodiversity of this group. We predict that future environmental PCR studies will significantly augment known biodiversity that we have discovered and demonstrate the Cyanidiales to be a species-rich branch of red algal evolution. PMID:15189206

Ciniglia, Claudia; Yoon, Hwan Su; Pollio, Antonino; Pinto, Gabriele; Bhattacharya, Debashish

2004-07-01

471

A novel obligate cultivation mutualism between damselfish and Polysiphonia algae  

PubMed Central

In cultivation mutualisms, farming animals prepare fields for cultivars, enhance their growth and harvest them. For example, in terrestrial ecosystems, plantherbivore cultivation mutualisms arose between humans and their crops only relatively recently. We discovered an obligate cultivation mutualism between a damselfish and an alga in a coral reef ecosystem. The damselfish, Stegastes nigricans, manages algal farms through territorial defence against the invading grazers and through weeding of unpalatable algae. As a result, the algal farms of S. nigricans are dominated by one species, Polysiphonia sp. We performed an exhaustive survey of algal assemblages inside and outside the territories of five damselfish species around the Ryukyu Islands, Japan, using molecular and morphological characteristics. Polysiphonia sp. 1 grew exclusively inside the farms of S. nigricans, and never elsewhere. Since only Polysiphonia sp. 1 is harvested and consumed by the damselfish as a staple food, this interdependent relationship is an obligate cultivation mutualism. This is the first record of an obligate plantherbivore cultivation mutualism in a marine ecosystem. Our data also suggest that three other Polysiphonia species are facultatively mutual with, commensal with, or parasitic on other damselfish species.

Hata, Hiroki; Kato, Makoto

2006-01-01

472

Spectrin-like proteins in green algae (Desmidiaceae).  

PubMed

Immunochemical detection of actin as well as spectrin-like proteins have been carried out in the green algae Micrasterias denticulata, Closterium lunula, and Euastrum oblongum. In these algae, actin is detected on Western blots at 43 kDa with antibodies to actin from higher plant and animal origin. By use of antibodies to human and chicken erythrocyte spectrin a cross-reactivity with desmid proteins is found at about the molecular mass of 220 kDa, where also human erythrocyte spectrin is detected. Additional bands are present at 120 kDa and 70 kDa, which are probably breakdown products. An antibody against chicken alpha-actinin, a small protein of the spectrin superfamily, recognizes bands at 90 kDa, where it is expected, and 70 kDa, probably the same breakdown product as mentioned for spectrin. Isoelectric focusing provides staining at pI 4.6 with antibodies against spectrin. Immunogold labelling of spectrin and alpha-actinin antigens on high-pressure frozen, freeze-substituted Micrasterias denticulata cells with the same antibodies exhibits staining, especially at membranes of different populations of secretory vesicles, at dictyosomes, and the plasma membrane. However, no clear correlation to the growth pattern of the cell could be observed. Taken together, our results demonstrate the presence of spectrin-like proteins in desmid cells which are probably functional in exocytosis. PMID:10579899

Holzinger, A; De Ruijter, N; Emons, A M; Ltz-Meindl, U

1999-01-01

473

A quantitative investigation of airborne algae and lichen soredia obtained from pollen traps in south-west Spain  

Microsoft Academic Search

Over the course of nearly a year, counts were made of the algae present in the samples from a Burkard-type volumetric aerobiological trap which sampled continuously the atmosphere of the city of Badajoz (SW Spain), yielding hourly and daily results. The method permits only the major taxa of algae to be distinguished. Most of the algae found belong to the

R. Tormo; D. Recio; I. Silva; A. F. Mu隳z

2001-01-01

474

Evaluation of the Contamination of Marine Algae (Seaweed) from the St. Lawrence River and Likely to Be Consumed by Humans  

Microsoft Academic Search

The goal of the study was to assess the contamination of marine algae (seaweeds) growing in the St. Lawrence River estuary and Gulf of St. Lawrence and to evaluate the risks to human health from the consumption of these algae. Algae were collected by hand at low tide. A total of 10 sites on the north and south shores of

Denise Phaneuf; Isabelle C矌; Pierre Dumas; Liliane A. Ferron; Alain LeBlanc

1999-01-01

475

Gut passage of phosphorus-limited algae through Daphnia : do they take up nutrients in the process?  

Microsoft Academic Search

Nutrient-limited algae are known to be a food source of inferior quality for zooplankters. Three factors are thought to determine this poor quality: direct elemental limitations of the algae, biochemical limitations and an increased resistance to diges- tion because of an increase in cell wall thickness. Thus far, most studies have concen- trated on the effect of the algae on

Maarten Boersma; Karen H. Wiltshire

2006-01-01

476

Phytochelatin production in freshwater algae Stigeoclonium in response to heavy metals contained in mining water; effects of some environmental factors  

Microsoft Academic Search

Production of phytochelatins (PC) in two freshwater, filamentous green algae of the genus Stigeoclonium, in response to heavy metals contained in mining water was studied. Stigeoclonium sp. grown abundantly in ditches with the mining water (southern Poland) accumulated high amounts of heavy metals. The other studied alga Stigeocloniumtenue Ktz. was isolated from unpolluted lake water in the Netherlands. Both algae

Barbara Pawlik-Skowro?ska

2001-01-01

477

Changes of cellular superficial configuration of symbiotic algae during cultivation from two anemones found in the South China Sea  

NASA Astrophysics Data System (ADS)

Symbiotic algae from two anemones, Radianthus macrodactylus and Stichodactyla mertensii, found in the South China Sea, were cultivated in ASP-8A medium in this study. Changes of superficial configuration of symbiotic algae during the cultivation were studied by means of a microscope and a scanning electron microscope (SEM). A number of small cavities appeared on the surfaces of symbiotic algae after they were cultivated for 10 h. The cavities enlarged and the cell contents were lost with extended cultivation. Our data suggested that the presence of cavities on symbiotic algae surfaces may be one of the main reasons for failure to culture symbiotic algae in an artificial medium.

Zhu, Baohua; Pan, Kehou; Wang, Guangce

2008-02-01

478

[The effect of chromium removal by algae-bacteria Bostrychia calliptera (Rhodomelaceae) consortia under laboratory conditions].  

PubMed

Water pollution is one of the most important environmental problems worldwide. Recently, biotechnology studies have oriented efforts to study algae-bacterium consortia with the aim to understand the mechanisms to find a possible solution in environmental sciences. This study determined the percentage of chromium removal by the alga-bacterium association exposed to a set of different chromium concentrations under controlled in vitro conditions. Wild plants of Bostrychia calliptera associated with bacterial populations were collected from Dagua River, Pacific coast of Colombia, and were monitored in the laboratory. The trial was conducted with synthetic seawater in bioreactors at two chromium levels: 5 and 10mg/L, and four different experimental treatments: i) algae-bacteria (AB), ii) algae with antibiotic (AA), iii) algal surface sediment, Natural Bacterial Consortium (CBN), and iv) the control without algae or bacteria. The experimental design followed a model of two factors (chromium concentration x combination types) with repeated measures using one factor. The microbial population behavior and the chromium concentration percentage were monitored by using atomic absorption spectroscopy (AAS). According to the data, Algae-bacteria (AB) treatment was the most efficient combination at 10mg/L (87%), whereas the bacterial consortia (CBN) was the most efficient at 5mg/L (62.85%). The results showed significant differences of chromium uptake between algae-bacteria (AB) and natural bacterial consortia (CBN), meaning the importance of those treatments in the chromium removal from coastal waters. PMID:23025079

Rengifo-Gallego, Ana Luc燰; Pe鎙-Salamanca, Enrique; Benitez-Campo, Neyla

2012-09-01

479

Natural impacted freshwaters: in situ use of alginate immobilized algae to the assessment of algal response.  

PubMed

The objective of this study was to investigate the feasibility of an in situ phytotoxicity test using alginate-immobilized algae for 60 days, in the assessment of water quality in an impacted small peri-urban stream. After laboratory optimization of algae immobilization/de-immobilization processes, the performance of immobilized/de-immobilized algae was compared to the performance of free algae in terms of specific algal growth and sensitivity. This was done by comparing 72 h EC50 values obtained with zinc and the pesticides clomazone and carbofuran. The results showed a similar performance, which allow us to conclude that immobilization for 60 days do not cause any significant alteration in algae physiology. In the field, immobilized algae were exposed at different times (2, 4 and 7 days) to water samples in both disturbed and undisturbed sites. Both laboratory and field experiments indicated that alginate-immobilized algae for 60 days were sufficiently sensitive for use in the in situ assessment of water quality. PMID:19247831

Corr獪, A X R; Tamanaha, M S; Horita, C O; Radetski, M R; Corr獪, R; Radetski, C M

2009-02-27

480

Feeding preferences and the nutritional value of tropical algae for the abalone Haliotis asinina.  

PubMed

Understanding the feeding preferences of abalone (high-value marine herbivores) is integral to new species development in aquaculture because of the expected link between preference and performance. Performance relates directly to the nutritional value of algae--or any feedstock--which in turn is driven by the amino acid content and profile, and specifically the content of the limiting essential amino acids. However, the relationship between feeding preferences, consumption and amino acid content of algae have rarely been simultaneously investigated for abalone, and never for the emerging target species Haliotis asinina. Here we found that the tropical H. asinina had strong and consistent preferences for the red alga Hypnea pannosa and the green alga Ulva flexuosa, but no overarching relationship between protein content (sum of amino acids) and preference existed. For example, preferred Hypnea and Ulva had distinctly different protein contents (12.64 vs. 2.99 g 100 g(-1)) and the protein-rich Asparagopsis taxiformis (>15 g 100 g(-1) of dry weight) was one of the least preferred algae. The limiting amino acid in all algae was methionine, followed by histidine or lysine. Furthermore we demonstrated that preferences can largely be removed using carrageenan as a binder for dried alga, most likely acting as a feeding attractant or stimulant. The apparent decoupling between feeding preference and algal nutritive values may be due to a trade off between nutritive values and grazing deterrence associated with physical and chemical properties. PMID:22719967

Angell, Alex R; Pirozzi, Igor; de Nys, Rocky; Paul, Nicholas A

2012-06-14