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1

Transformation of trans Golgi Network During the Cell Cycle in a Green Alga, Botryococcus braunii  

Microsoft Academic Search

trans-Golgi network (TGN), and the changes in its structure and behavior throughout the cell cycle of a unicellular green alga,\\u000a Botryococcus braunii, were examined with deep-etching replicas and in cryo-fixed\\/freeze-substituted specimens. In interphase cells, the TGN consisted\\u000a of a hemispherically shaped cisterna (TGN-cisterna) with regularly distributed pores on the surface and a tubular network\\u000a (TGN-tubules) with clathrin-coated vesicles. The TGNs

Tetsuko Noguchi; Fukiko Kakami

1999-01-01

2

Study of the mechanism of biosynthesis of non terpenic hydrocarbons in green alga Botryococcus braunii: Synthesis of labelled intermediates.  

National Technical Information Service (NTIS)

In order to demonstrate the mechanism of elongation-decarboxylation in the development of hydrocarbons of the Botryococcus braunii algae, various radioactive substrates with very long chain have been synthetized: C28 ester, C28 beta-cetoester, C28, C30 an...

T. P. Mong-Sin

1985-01-01

3

Active Hydrocarbon Biosynthesis and Accumulation in a Green Alga, Botryococcus braunii (Race A)  

PubMed Central

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

Hirose, Mana; Mukaida, Fukiko; Okada, Sigeru

2013-01-01

4

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

PubMed

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

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

2013-08-01

5

Colony Organization in the Green Alga Botryococcus braunii is Specified by a Complex Extracellular Matrix  

SciTech Connect

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

Weiss, Taylor [Texas A& M University; Roth, Robyn [Washington University of St. Louis; Goodson, Carrie [Washington University of St. Louis; Vithda, Stanislav [Texas A& M University; Black, Ian [University of Georgia; Azadi, Parastoo [University of Georgia; Rusch, Jannette [Washington University of St. Louis; Holzenburg, Andreas [Texas A& M University; Devarenne, Timothy [Texas A& M University; Goodenough, Ursula [Washington University of St. Louis

2012-01-01

6

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

PubMed Central

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

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

2013-01-01

7

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

PubMed

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

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

2013-01-01

8

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

9

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

PubMed

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

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

2012-12-01

10

Colony Organization in the Green Alga Botryococcus braunii (Race B) Is Specified by a Complex Extracellular Matrix  

PubMed Central

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

Weiss, Taylor L.; Roth, Robyn; Goodson, Carrie; Vitha, Stanislav; Black, Ian; Azadi, Parastoo; Rusch, Jannette; Holzenburg, Andreas

2012-01-01

11

Biogasification of Marine Algae: Nannochloropsis oculata and Botryococcus braunii (BRIEFING SLIDES).  

National Technical Information Service (NTIS)

Algae has the potential to be a useful source of biomass derived energy due to the high lipid content and rapid growth rate of the organism. Currently, there are many methods available to harvest the energy from algae, such as transesterification of lipid...

P. Pullammanappallil R. A. Diltz S. Buxy

2010-01-01

12

Studies on batch and continuous cultures of Botryococcus braunii: hydrocarbon production in relation to physiological state, cell ultrastructure, and phosphate nutrition  

Microsoft Academic Search

The growth of the hydrocarbon-rich alga Botryococcus braunii was studied under air-lift conditions using batch and continuous cultures. Large variations in the physiological state of B. braunii were achieved in batch cultures and in continuous cultures with various dilution rates. The possible effects of these variations upon hydrocarbons (nature, relative abundance, location, level, productivity) and also on the production of

E. Casadevall; D. Dif; C. Largeau; C. Gudin; D. Chaumont; O. Desanti

1985-01-01

13

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

14

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

Microsoft Academic Search

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

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

15

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

PubMed

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

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

2013-06-01

16

Brefeldin A effects on the trans-Golgi network and Golgi bodies in Botryococcus braunii are not uniform during the cell cycle  

Microsoft Academic Search

Summary Using cryo-fixation and freeze-substitution electron microscopy, the effects of brefeldin A (BFA) on the structure of the trans-Golgi network (TGN), the endoplasmic reticulum (ER), and Golgi bodies in the unicellular green algaBotryococcus braunii were examined at various stages of the cell cycle. In the presence of BFA, all the TGNs of interphase and dividing cells aggregated to form a

Tetsuko Noguchi; Hisae Watanabe

1999-01-01

17

Effect of media and culture conditions on growth and hydrocarbon production by Botryococcus braunii  

Microsoft Academic Search

The influence of the media constituents potassium nitrate, magnesium sulphate, dihydrogen potassium phosphate and ferric citrate on growth and hydrocarbon production in Botryococcus braunii (SAG 30.81) was investigated using response surface methodology (RSM). Among the individual variables, potassium nitrate and ferric citrate exhibited marked effects on the response functions (yield of biomass and hydrocarbon production). A high correlation coefficient (r?0.93,

C. Dayananda; R. Sarada; Sila Bhattacharya; G. A. Ravishankar

2005-01-01

18

Fatty acids in Botryococcus braunii accelerate topical delivery of flurbiprofen into and across skin.  

PubMed

To improve the drug absorption into and across the skin, fatty acids extracted from Botryococcus braunii were evaluated using in vitro and in vivo techniques with Wistar rats as the animal model. Palmitic acid (C16:0), oleic acid (C18:1), linoleic acid (C18:2), and linolenic acid (C18:3) were the major components in the B. braunii extract. Topical delivery of flurbiprofen was significantly enhanced after pretreatment with 3% B. braunii extract for 30min in an in vitro Franz cell and in vivo pharmacokinetic studies. Pure unsaturated fatty acids were more-effective enhancers than the B. braunii extract. However, a greater irritant potential was also observed with those fatty acids than with the B. braunii extract according to the skin tolerance study as determined by transepidermal water loss (TEWL). Both human keratinocytes and skin fibroblasts showed a 1.5-2-fold increase in prostaglandin E(2) (PGE(2)) release as compared to the control. The findings in this study indicate that the fatty acids in B. braunii may be useful enhancers for flurbiprofen delivery via the skin. PMID:15113623

Fang, Jia-You; Chiu, Hsien-Chih; Wu, Jiunn-Tzong; Chiang, Yin-Ru; Hsu, Shu-Hui

2004-05-19

19

Botryococcus braunii cells: Ultrasound-intensified outdoor cultivation integrated with in situ magnetic separation.  

PubMed

An integrated system combining ultrasound-intensified outdoor cultivation of Botryococcus braunii with in situ magnetic harvesting of the algal cells was developed. The algal cells were cultivated in 200L plastic bag reactors, and seven five-minute ultrasonic treatments at a four-day interval using a fixed frequency of 40kHz and a total power of 300W improved algal cell biomass and hydrocarbon productivity. The algal cells were harvested using functional magnetic particles and a magnetic separator, and a recovery efficiency of 90% was obtained under continuous operation at a flow rate of 100mL/min using the in situ magnetic separation system. The overall production cost using the integrated system was US$ 25.14 per kilogram of B. braunii dry biomass. The system developed in this study provides a base for the industrial production of B. braunii. PMID:24998478

Wang, Shi-Kai; Wang, Feng; Stiles, Amanda R; Guo, Chen; Liu, Chun-Zhao

2014-09-01

20

Alkane biosynthesis by decarbonylation of aldehyde catalyzed by a microsomal preparation from Botryococcus braunii.  

PubMed

The final step in the synthesis of n-hydrocarbons in an animal and a higher plant involves enzymatic decarbonylation of aldehydes to the corresponding alkanes by loss of the carbonyl carbon. Whether such a novel reaction is involved in hydrocarbon synthesis in the colonial microalga, Botryococcus braunii, which is known to produce unusually high levels (up to 32% of dry weight) of n-C27, C29, and C31 alka-dienes and -trienes, was investigated. Dithioerythritol severely inhibited the incorporation of [1-14C]acetate into these hydrocarbons with accumulation of the label in the aldehyde fraction in the B. braunii cells. Microsomal preparations of the alga synthesized alkane from fatty acid and aldehyde in the absence of O2. Conversion of fatty acid to alkane required CoA, ATP, and NADH, whereas conversion of aldehyde to alkane did not require the addition of cofactors. That the alkane synthesis involves a decarbonylation was shown by the production of CO and heptadecane from octadecanal. CO was identified by adsorption to RhCl[(C6H6)3P]3. The decarbonylase had a pH optimum at 7.0, an apparent Km of 65 microM, a Vmax of 1.36 nmol/min/mg and was inhibited by the metal chelators EDTA, O-phenanthroline and 8-hydroxyquinoline. It was stimulated nearly threefold by 2 mM ascorbate and inhibited by the presence of O2. A partial (28%) retention of the aldehydic hydrogen of [1-3H]octadecanal in the heptadecane was observed; the remaining 3H was lost to H2O. The microsomal preparation also catalyzed the oxidation of 14CO to 14CO2, with a pH optimum of 7.0. This accounts for the nonstoichiometry of CO to heptadecane observed. In vivo studies with 14CO showed that the label was incorporated into metabolic products. This metabolic conversion of CO, not found in the previously examined hydrocarbon synthesizing systems, may be necessary for organisms that produce large amounts of hydrocarbons such as the present alga. The mechanism of the decarbonylation and the nature of the decarbonylase remain to be elucidated. PMID:1898004

Dennis, M W; Kolattukudy, P E

1991-06-01

21

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

NASA Astrophysics Data System (ADS)

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

Zhang, Z.; Sachs, J. P.

2004-12-01

22

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

2010-04-01

23

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

24

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

SciTech Connect

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

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

1993-09-01

25

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

26

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

27

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

SciTech Connect

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

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

1993-12-31

28

Formation and decomposition of vacuoles in Botryococcus in relation to the trans-Golgi network  

Microsoft Academic Search

Summary The formation and the decomposition of vacuoles in a member of Xanthophyceae,Botryococcus braunii, were examined by light and electron microscopy. Particles around the nucleus were identified as vacuoles from their stainability with neutral red. These particles disappeared during cell division. They reacted positively in an activity test for acid phosphatase. Electron microscopy revealed the presence of spherical vacuoles around

Tetsuko Noguchi

1994-01-01

29

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

NASA Astrophysics Data System (ADS)

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

Ratanasthien, Benjavun

1999-04-01

30

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

PubMed

The immobilized biofilm cultivation was a promising method to greatly improve the biomass productivity of microalga Botryococcus braunii, which was considered as an feedstock of renewable biofuel. In this research, the effects of different nitrogen sources and supply methods on growth and hydrocarbon production of B. braunii under immobilized biofilm cultivation (attached cultivation) were studied. Of the total 5 different nitrogen sources, NaNO3 was selected as the best one with which the high biomass productivity and hydrocarbon productivity of 6.45gm(-2)d(-1) and 2.79gm(-2)d(-1) were obtained respectively. The optimized nitrogen concentration was 0.99mM for non-circulating medium supply model, while for the circulating model, the optimized nitrogen concentration as well as medium volume was 1.49mM and 1.2L, respectively. Furthermore, nitrogen inputs based on growth of 1kg dry algae biomass was only 28.92g with circulating model. Attached cultivation was high efficient in light, nutrient and water utilization. PMID:24951939

Cheng, Pengfei; Wang, Junfeng; Liu, Tianzhong

2014-08-01

31

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

SciTech Connect

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

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

1993-05-01

32

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

33

Algae.  

PubMed

Algae frequently get a bad press. Pond slime is a problem in garden pools, algal blooms can produce toxins that incapacitate or kill animals and humans and even the term seaweed is pejorative - a weed being a plant growing in what humans consider to be the wrong place. Positive aspects of algae are generally less newsworthy - they are the basis of marine food webs, supporting fisheries and charismatic marine megafauna from albatrosses to whales, as well as consuming carbon dioxide and producing oxygen. Here we consider what algae are, their diversity in terms of evolutionary origin, size, shape and life cycles, and their role in the natural environment and in human affairs. PMID:25004359

Raven, John A; Giordano, Mario

2014-07-01

34

Performance of an enzymatic extract in Botrycoccus braunii cell wall disruption.  

PubMed

Microalgae can produce and contain lipids, proteins and carbohydrates, which can be extracted and marketed as potential novel added-value bio-products. However, microalgae cell wall disruption is one of the most important challenges involved while processing this type of biomass. In this context, white-rot fungi, responsible for the biodegradation of lignin present in wood due to non-specific extracellular enzymes, could be applied for promoting microalgae cell wall degradation. Therefore, the aim of this study was to evaluate the use of an enzymatic extract produced by the white-rot fungi Anthracophyllum discolor as a biotechnological tool for Botryococcus braunii cell wall disruption. The fungus was inoculated in wheat grains and manganese peroxidase (MnP) activity was monitored while obtaining the enzymatic extract. Then, cell wall disruption trials with different MnP activity were evaluated by the biochemical methane potential (BMP). In relation to cell wall disruption, it was observed that the optimal value was obtained with enzymatic concentration of 1000 U/L with a BMP of 521 mL CH4/g VS. Under these conditions almost 90% of biomass biodegradability was observed, increasing in 62% compared to the microalgae without treatment. Therefore, the results indicate that enzymes secreted by A. discolor promoted the attack of the different cell wall components finally weakening it. Therefore, the application of this treatment could be a promissory biotechnological approach to decrease the energetic input required for the cell wall disruption step. PMID:23899898

Ciudad, Gustavo; Rubilar, Olga; Az鏂ar, Laura; Toro, Claudio; Cea, Mara; Torres, 翼varo; Ribera, Alejandra; Navia, Rodrigo

2014-01-01

35

Removal of CO(sub 2) from flue gases by algae. (Quarterly) technical report, March 1, 1993--May 31, 1993.  

National Technical Information Service (NTIS)

The objective of this research program is to determine the feasibility of the alga Botrvococcus braunii as a biocatalyst for the photosynthetic conversion of flue gas CO(sub 2) to hydrocarbons. The research program involves the determination of the biocat...

C. Akin S. Pradhan

1993-01-01

36

Botryococcene - A tetramethylated acyclic triterpenoid of algal origin  

NASA Technical Reports Server (NTRS)

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

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

1973-01-01

37

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

38

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

NASA Astrophysics Data System (ADS)

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

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

2010-05-01

39

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

USGS Publications Warehouse

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

Mastalerz, M.; Hower, J. C.

1996-01-01

40

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

PubMed Central

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

2010-01-01

41

Algae Experiments  

NSDL National Science Digital Library

This two-part lesson offers students the opportunity to view two types of algae (freshwater and Great Salt Lake species) and assess the survival of each when placed in altered habitats. Students will make observations and record their observations on a recording sheet where they will describe what they see through drawing and words. They will help prepare slides of algae and will learn to identify different qualities such as cell structure, movement and other behavioristic qualities of the two different types of algae. The resource includes background knowledge, reference to Utah elementary core curriculum standards, prior resource assessment, reproducible handouts, materials list, teaching recommendations, and final assessment strategies.

Duffy, Kim; Project, Westminster C.

42

Green Algae  

NSDL National Science Digital Library

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

Van Egmond, Wim

2010-01-01

43

[Glutamate dehydrogenases of unicellular green algae: effects of nitrate and ammonium in vivo].  

PubMed

The constitution and control by the inorganic nitrogen source of glutamate dehydrogenases of some unicellular green algae have been studied. The Ankistrodesmus braunii and Scenedesmus obliquus cells contain two different glutamate dehydrogenases, one of which is NADP-specific, the other is active with both NAD and NADP. Their synthesis does not depend on the nitrogen source. The activity of NADP-specific glutamate dehydrogenase increases sharply during nitrogen starvation. In Chlorella pyrenoidosa 82 and Ch. ellipsoidea only one constitutive double specific glutamate dehydrogenase is observed. Its activity does not change depending on the nitrogen nutrition conditions. In the cells of the thermophylic Chlorella strain Chlorella sp. K. ammomium induces a de novo synthesis of NADP-specific glutamate dehydrogenase in addition to the constitutive double specific glutamate dehydrogenase. Thus, the algae tested contain constitutive double specific glutamate dehydrogenase. The NADP-specific enzyme is absent in two Chlorella strains, is constitutive in A. braunii and S. obliquus, and is ammonium-inducible in three thermophylic Chlorella strains. PMID:25679

Shatilov, V R; Sofbin, A V; Kasatkina, T I; Zabrodina, T M; Vladimirova, M G; Kretovich, V L

1978-02-01

44

The mechanism of hydrogen photoproduction by several algae : II. The contribution of photosystem II.  

PubMed

The contribution of PS II to H2 photoproduction by several unicellular green algae was measured both when O2 evolution and photophosphorylation were unimpaired and also when these processes had been eliminated by Cl-CCP. As judged by the effects of DCMU, a PS II contribution was found under both sets of experimental conditions for several strains of Chlorella, Ankistrodesmus and Scenedesmus. However, H2 photoproduction by Chlamydomonas moewusii was insensitive to DCMU and thus was entirely due to PS I. With cells treated with Cl-CCP, the relative amount of PS II contribution varied from zero in autotrophically grown Chlamydomonas reinhardii, to ? 20% in photoheterotrophically grown and ? 50% in autotrophically grown cells of Ankistrodesmus braunii, Chlorella fusca, Chlorella vulgaris and Scenedesmus obliquus. The dehydrogenation of reduced H-donors by PS II of Scenedesmus treated with Cl-CCP showed the same biphasic kinetics previously described for H2 photoproduction by PS I of this alga. PMID:24477952

Stuart, T S; Gaffron, H

1972-06-01

45

Low-power 2.45-GHz microwave radiation affects neither the vacuolar potential nor the low frequency excess noise in single cells of characean algae.  

PubMed

Single, giant cells of the eukaryotic green algae Chara braunii and Nitella flexilis were subjected to short-, intermediate-, and long-term irradiations with 2.45-GHz microwaves. A search was carried out for radiation-correlated shifts (i) in both the dc level and the rms low-frequency excess noise of the vacuolar potential and (ii) in the membrane resistivity. No reliable shifts were observed, either in normal cells or in cells subjected to reduced temperatures or the poison ethacrynic acid. PMID:3847506

Gokhale, A V; Pickard, W F; Brunkard, K M

1985-01-01

46

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

47

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

48

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

49

ALGAE AND WATER POLLUTION  

EPA Science Inventory

Algae are involved in water pollution in a number of important ways. It requires a continuous monitoring and study of algae existing in waters of various quality in order to determine what controls or what changes or what uses can be instituted for the benefit of man and for cons...

50

AlgaeBase  

NSDL National Science Digital Library

AlgaeBase offers a free database of information on algae species around the world. This project is part of the Species 2000 initiative, created to enumerate "all known species of plants, animals, fungi and microbes on Earth as the baseline dataset for studies of global biodiversity." User may search the database for literature citations and photographs for algae identified by genus, species, or common name. The photographs, mostly of Irish species, are well referenced and often quite beautiful. Currently the seaweed data are most complete, but additional data are frequently added. Both the Web site and the database are straightforward and easy to use.

Dhonncha, Eilis N.; Guiry, Michael D.

51

Grow Your Own Algae!  

NSDL National Science Digital Library

Students discover how tiny microscopic plants can remove nutrients from polluted water. They also learn how to engineer a system to remove pollutants faster and faster by changing the environment for the algae.

STARS GK-12 Program,

52

Harmful Algae Digital Library  

NSDL National Science Digital Library

The Harmful Algae Digital Library contains a collection of Sea Grant documents in digital format (primarily PDF) arranged by subject area: red tide/PSP, brown tide, ciguatera, killer algae, and Pfiesteria. This collection is part of the National Sea Grant Library (NSGL), which maintains over 36,000 searchable records dedicated to environmental stewardship, long-term economic development and responsible use of America's coastal, ocean and Great Lakes resources.

Library, National S.; University Of Rhode Island-Bay Campus, Noaa

53

The Harmful Algae Page  

NSDL National Science Digital Library

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

Anderson, Donald

2004-06-17

54

Algae Harvest Energy Conversion  

Microsoft Academic Search

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

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

55

Pharmaceuticals from cultured algae  

Microsoft Academic Search

Summary An algae screening program, including cultured macroalgae, cultured cyanobacteria and cultured eukaryotic microalgae has been undertaken. Methods for the isolation, purification, preservation and cultivation of axenic cyanobacteria and eukaryotic cultures have been developed. Screening of these groups for biologically active components has lead to the isolation of pachydictyol and caulerpenyne from cultured macroalgae, while a series of hapalindoles and

Robert E. Schwartz; Charles F. Hirsch; David F. Sesin; James E. Flor; Michel Chartrain; Robert E. Fromtling; Guy H. Harris; Michael J. Salvatore; Jerrold M. Liesch; Katherine Yudin

1990-01-01

56

Heterotrophic Growth of Algae.  

National Technical Information Service (NTIS)

Whereas most algae can efficiently provide for most nutrient needs via photosynthesis, growth can be maintained in the dark or under conditions of low CO sub 2 tension provided a suitable carbon source is available. This paper describes the growth of Scen...

Z. Sikora

1987-01-01

57

The Great Algae Race  

NSDL National Science Digital Library

In a multi-week experiment, student groups gather data from the photobioreactors that they build to investigate growth conditions that make algae thrive best. Using plastic soda bottles, pond water and fish tank aerators, they vary the amount of carbon dioxide (or nutrients or sunlight, as an extension) available to the microalgae. They compare growth in aerated vs. non-aerated conditions. They measure growth by comparing the color of their algae cultures in the bottles to a color indicator scale. Then they graph and analyze the collected data to see which had the fastest growth. Students learn how plants biorecycle carbon dioxide into organic carbon (part of the carbon cycle) and how engineers apply their understanding of this process to maximize biofuel production.

Membrane Biotechnology Laboratory

58

Sustainable biofuels from algae  

Microsoft Academic Search

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

Michael Armin Borowitzka; Navid Reza Moheimani

59

The Harmful Algae Page  

NSDL National Science Digital Library

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

., Woods H.

1997-01-01

60

Fuel From Algae: Scaling and Commercialization of Algae Harvesting Technologies  

SciTech Connect

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

None

2010-01-15

61

Biological importance of marine algae  

PubMed Central

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

El Gamal, Ali A.

2009-01-01

62

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

63

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

64

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

65

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

66

Plant biomechanics: High-endurance algae  

NASA Astrophysics Data System (ADS)

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

Carrington, Emily

2013-11-01

67

Formation of algae growth constitutive relations for improved algae modeling.  

SciTech Connect

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

Gharagozloo, Patricia E.; Drewry, Jessica L.

2013-01-01

68

Primary Shewanella algae bacteremia mimicking Vibrio septicemia.  

PubMed

Shewanella algae infections are rare in humans. Previously reported cases of S. algae have mainly been associated with direct contact with seawater. We report a case of primary S. algae bacteremia occurring after the ingestion of raw seafood in a patient with liver cirrhosis that presented a fulminent course of necrotizing fasciitis. PMID:19949681

Myung, Dae Seong; Jung, Young-Sun; Kang, Seung-Ji; Song, Young A; Park, Kyung-Hwa; Jung, Sook-In; Kim, Soo Hyun; Shin, Jong-Hee

2009-12-01

69

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

70

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

71

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

72

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 others

Niskern, Diana, Comp.

73

Phytochelatin production in marine algae  

Microsoft Academic Search

Abstract Phytochelatins are metal-binding peptides produced enzymatically by higher plants, fungi, and algae in response to many metals, particularly Cd. We have studied phytochelatin production in several marine phytoplankton exposed to a range of free Cd ion concentrations. As a result of increased analytical resolution, we have found that all the species contain phytochelatin, even when there is no added

B. A. Ahner; F. M. M. Morel

1995-01-01

74

Cultivation of Macroscopic Marine Algae.  

National Technical Information Service (NTIS)

The red alga Gracilaria tikvahiae may be grown outdoors year-round in central Florida with yields averaging 35.5 g dry wt/m exp 2 .day, greater than the most productive terrestrial plants. This occurs only when the plants are in a suspended culture, with ...

J. H. Ryther

1982-01-01

75

Responses of certain freshwater planktonic algae to fluoride  

Microsoft Academic Search

The effects of dissolved fluoride supplied as NaF at up to 150 p.p.m. F (7.9 mM) on growth, photosynthesis, dark respiration, enolase activity and fluoride uptake were determined for six phytoplankters: Synechococcus leopoliensis (Racib.) Komarek (Cyanophyta), Oscillatoria limnetica Lemmermann (Cyanophyta), Ankistrodesmus braunii Brun (Chlorophyta), Scenedesmus quadricauda (Turp.) Breb. (Chlorophyta), Cyclotella meneghiniana Kuetzing (Bacillariophyta) and Stephanodiscus minutus Grun. ex Cleve et

W. E. Hekman; K. Budd; G. R. Palmer; J. D. MacArthur

1984-01-01

76

Biotransformation of benzo[a]pyrene and other polycyclic aromatic hydrocarbons and heterocyclic analogs by several green algae and other algal species under gold and white light.  

PubMed

This laboratory has shown that the metabolism of benzo[a]pyrene (BaP), a carcinogenic polycyclic aromatic hydrocarbon (PAH), by a freshwater green alga, Selenastrum capricornutum, under gold light proceeds through a dioxygenase pathway with subsequent conjugation and excretion. This study was undertaken to determine: (1) the effects of different light sources on the enzymatic or photochemical processes involved in the biotransformation of BaP over a dose range of 5-1200 mg/l; (2) the phototoxicity of carcinogenic PAHs and mutagenic quinones to a green alga; (3) the ability of other algal systems to metabolize BaP. Cultures were exposed to different doses of BaP for 2 days at 23 degrees C under gold, white or UV-A fluorescent light on a diurnal cycle of 16 h light, 8 h dark. Under gold light, metabolites of BaP produced by Selenastrum capricornutum were the dihydrodiols of which the 11,12-dihydrodiol was the major metabolite. Under white light, at low doses, the major metabolite was the 9,10-dihydrodiol. With increasing dose, the ratio of dihydrodiols to quinones decreased to less than two. With increasing light energy output, from gold to white to UV-A in the PAH absorbing region, BaP quinone production increased. Of other carcinogenic PAHs studied, only 7H-dibenz[c,g]carbazole was as phototoxic as BaP while 7,12-dimethylbenz[a]anthracene, dibenz[a,j]acridine and non-carcinogenic PAHs, anthracene and pyrene, were not phototoxic. The 3,6-quinone of BaP was found to be highly phototoxic while quinones that included menadione, danthron, phenanthrene-quinone and hydroquinone were not. The data suggest that the phototoxicity of BaP is due to photochemical production of quinones; the 3,6-quinone of BaP is phototoxic and is probably the result of the production of short lived cyclic reactive intermediates by the interaction of light with the quinone. Lastly, only the green algae, Selenastrum capricornutum, Scenedesmus acutus and Ankistrodesmus braunii almost completely metabolized BaP to dihydrodiols. The green alga Chlamydomonas reinhardtii, the yellow alga Ochromonas malhamensis, the blue green algae Anabaena flosaquae and euglenoid Euglena gracilis did not metabolize BaP to any extent. The data indicate that algae are important in their ability to degrade PAHs but the degradation is dependent on the dose of light energy emitted and absorbed, the dose of PAHs to which the algae are exposed, the phototoxicity of PAHs and their metabolite(s) and the species and strain of algae involved. All of these factors will be important in assessing the degradation and detoxification pathways of recalcitrant PAHs by algae. PMID:7606812

Warshawsky, D; Cody, T; Radike, M; Reilman, R; Schumann, B; LaDow, K; Schneider, J

1995-07-14

77

The remote sensing of algae  

NASA Technical Reports Server (NTRS)

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

Thorne, J. F.

1977-01-01

78

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

79

The Systematics of Subaerial Algae  

Microsoft Academic Search

\\u000a Over the past millions of years the land on our planet has been the testing ground for many experiments or, more dramatically,\\u000a the battleground for many invasions. A myriad of ancestral plant forms came from the sea and lakes to exploit the terrestrial\\u000a environment. Those life forms were algae, simple photoautotrophic organisms that eventually prepared the land for the terrestrial

Juan M. Lopez-Bautista; Fabio Rindi; Dale Casamatta

80

Parasites in algae mass culture  

PubMed Central

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

Carney, Laura T.; Lane, Todd W.

2014-01-01

81

Parasites in algae mass culture.  

PubMed

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

Carney, Laura T; Lane, Todd W

2014-01-01

82

Synthetic polyester from algae oil.  

PubMed

Current efforts to technically use microalgae focus on the generation of fuels with a molecular structure identical to crude oil based products. Here we suggest a different approach for the utilization of algae by translating the unique molecular structures of algae oil fatty acids into higher value chemical intermediates and materials. A crude extract from a microalga, the diatom Phaeodactylum tricornutum, was obtained as a multicomponent mixture containing amongst others unsaturated fatty acid (16:1, 18:1, and 20:5) phosphocholine triglycerides. Exposure of this crude algae oil to CO and methanol with the known catalyst precursor [{1,2-(tBu2 PCH2 )2 C6 H4 }Pd(OTf)](OTf) resulted in isomerization/methoxycarbonylation of the unsaturated fatty acids into a mixture of linear 1,17- and 1,19-diesters in high purity (>99?%). Polycondensation with a mixture of the corresponding diols yielded a novel mixed polyester-17/19.17/19 with an advantageously high melting and crystallization temperature. PMID:24845347

Roesle, Philipp; Stempfle, Florian; Hess, Sandra K; Zimmerer, Julia; R甐 B嫫tulos, Carolina; Lepetit, Bernard; Eckert, Angelika; Kroth, Peter G; Mecking, Stefan

2014-06-23

83

Stochastic Forecasting of Algae Blooms in Lakes  

SciTech Connect

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

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

2013-01-15

84

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

85

Electrocoagulationflotation process for algae removal  

Microsoft Academic Search

Algae in surface water have been a long-term issue all over the world, due to their adverse influence on drinking water treatment process as well as drinking water quality. The algae removal by electro-coagulationflotation (ECF) technology was investigated in this paper. The results indicated that aluminum was an excellent electrode material for algae removal as compared with iron. The optimal

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

2010-01-01

86

Analysis of neutral lipids from microalgae by HPLC-ELSD and APCI-MS/MS.  

PubMed

A method was developed to analyze neutral lipids through the use of three triglycerides, four free fatty acids, six di- and four mono-glycerides standards by high performance liquid chromatography (HPLC) normal phase coupled with either with evaporative light scattering detector (ELSD) or with mass spectrometry (MS) operating in atmospheric pressure chemical ionization (APCI) mode. The method was applied to the determination of the neutral lipid fraction from a Botryococcus braunii race A (B. braunii) culture. This method led us to identify neutral lipids synthesized by B. braunii in a single analysis within 45min through HPLC-APCI-MS/MS technique. PMID:24239934

Donot, F; Cazals, G; Gunata, Z; Egron, D; Malinge, J; Strub, C; Fontana, A; Schorr-Galindo, S

2013-12-30

87

Hydrocarbon feedstocks from algae hydrogenation  

SciTech Connect

A hydrogenation process for converting algae (Chlorella pyrenoidosa) to liquid products was developed. The hydrogenation was carried out in a batch autoclave at temperatures between 340 and 430 K and hydrogen pressures between 1 and 150 atm in the presence of a catalyst and a solvent. Yields of up to 50% oil in the C/sub 16/-C/sub 24/ range resulted, and by-products of ammonium carbonate and hydrocarbon gases were obtained. A kinetic model fitting the data quite well indicated that an asphaltenic substance was a reaction intermediate under all processing conditions.

Chin, L.Y.; Engel, A.J.

1981-01-01

88

F-BF Lake Algae  

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: On June 1, a fast growing species of algae is accidentally introduced into a lake in a city park. It starts to grow and cover the surface of the lake i...

89

A SURVEY OF ANTARCTIC ALGAE FOR AGGLUTININS  

Microsoft Academic Search

Since the discovery of haemagglutinating activity in marine algal extracts in 1966, several algal haemagglutinins (lectins) have been detected, isolated and characterized. However, information is slowly emerging, concerning biochemical characteristics of lectins from Antarctic marine algae. Lectins are proteins or glycoproteins which bind, reversibly, to carbohydrates. Eighteen species of Antarctic marine algae have been tested for the presence of haemagglutinins

Bartolomeu Warlene; S. de Souza; D嫫lio In塶io; A. Teixeira; F墎ia Karine Andrade; M嫫cia Rbia; S. Melo; Andres Mansilla Mu隳z; Ana Lcia; P. Freitas

90

Factors Influencing Metal Accumulation by Algae.  

National Technical Information Service (NTIS)

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 ...

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

1982-01-01

91

Nutritional And Taste Characteristics Of Algae  

NASA Technical Reports Server (NTRS)

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

Karel, M.; Nakhost, Z.

1992-01-01

92

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...

93

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

94

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

95

Cultivation of macroscopic marine algae  

SciTech Connect

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

Ryther, J.H.

1982-11-01

96

Composting of waste algae: a review.  

PubMed

Although composting has been successfully used at pilot scale to manage waste algae removed from eutrophied water environments and the compost product applied as a fertiliser, clear guidelines are not available for full scale algae composting. The review reports on the application of composting to stabilize waste algae, which to date has mainly been macro-algae, and identifies the peculiarities of algae as a composting feedstock, these being: relatively low carbon to nitrogen (C/N) ratio, which can result in nitrogen loss as NH3 and even N2O; high moisture content and low porosity, which together make aeration challenging; potentially high salinity, which can have adverse consequence for composting; and potentially have high metals and toxin content, which can affect application of the product as a fertiliser. To overcome the challenges that these peculiarities impose co-compost materials can be employed. PMID:24602833

Han, Wei; Clarke, William; Pratt, Steven

2014-07-01

97

Flocculation of model algae under shear.  

SciTech Connect

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

Pierce, Flint; Lechman, Jeremy B.

2010-11-01

98

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

99

Algae biodiesel - a feasibility report  

PubMed Central

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

2012-01-01

100

Process for cultivation of algae  

US Patent & Trademark Office Database

The present invention provides a tissue culture method for cultivation of marine algae, said method comprising the steps of (i) establishing axenic viable algal material by sequential treatment thereof in sterile sea water supplemented with domestic liquid detergent, incubating the treated material, (ii) culturing the axenic explants on agarified medium for induction of callus; (iii) excising and subculturing the calli from the axenic explants on fresh agar plates to obtain differentiated densely pigmented oval or spherical shaped micro-propagules (iv) subculturing the pigmented calli in agarified medium to achieve enhanced somatic embryogenesis and micro-propagule formation in pigmented filamentous callus, (v) transferring the filamentous calli with somatic embryos for morphogenesis and development of young plantlets; and (vi) cultivating algal biomass on a large scale by growing the young plantlets in enclosed perforated polythene bags.

2005-02-22

101

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

102

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

103

The Study of Development Using Red Algae  

NSDL National Science Digital Library

This exercise can be used to demonstrate developmental processes at the cellular level, environmental control of photosynthesis, and cell enlargement by using red algae, which is well-suited for these types of experiments.

Susan D. Waaland (University of Washington;)

1982-06-21

104

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

105

Alkanes and Alkenes in Marine Benthic Algae.  

National Technical Information Service (NTIS)

Saturated and olefinic hydrocarbons were determined in additional species of benthic marine algae from the Cape Cod Massachusetts area. The distribution of homologous and isomeric olefins was studied in plants of different age and in morphologically diffe...

W. W. Youngblood M. Blumer

1973-01-01

106

Regulation of Oil Biosynthesis in Algae.  

National Technical Information Service (NTIS)

Many algae including Chlamydomonas accumulate triacylglycerols when cultures enter stationary phase leading to nutrient limitation. The identification of microalgal genes encoding the enzymes and regulatory factors required for the induction of oil biosyn...

C. Benning E. R. Moellering M. Fedewa R. Miller

2008-01-01

107

Carotenoids in Algae: Distributions, Biosyntheses and Functions  

PubMed Central

For photosynthesis, phototrophic organisms necessarily synthesize not only chlorophylls but also carotenoids. Many kinds of carotenoids are found in algae and, recently, taxonomic studies of algae have been developed. In this review, the relationship between the distribution of carotenoids and the phylogeny of oxygenic phototrophs in sea and fresh water, including cyanobacteria, red algae, brown algae and green algae, is summarized. These phototrophs contain division- or class-specific carotenoids, such as fucoxanthin, peridinin and siphonaxanthin. The distribution of ?-carotene and its derivatives, such as lutein, loroxanthin and siphonaxanthin, are limited to divisions of Rhodophyta (macrophytic type), Cryptophyta, Euglenophyta, Chlorarachniophyta and Chlorophyta. In addition, carotenogenesis pathways are discussed based on the chemical structures of carotenoids and known characteristics of carotenogenesis enzymes in other organisms; genes and enzymes for carotenogenesis in algae are not yet known. Most carotenoids bind to membrane-bound pigment-protein complexes, such as reaction center, light-harvesting and cytochrome b6f complexes. Water-soluble peridinin-chlorophyll a-protein (PCP) and orange carotenoid protein (OCP) are also established. Some functions of carotenoids in photosynthesis are also briefly summarized.

Takaichi, Shinichi

2011-01-01

108

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

109

Carotenoids in algae: distributions, biosyntheses and functions.  

PubMed

For photosynthesis, phototrophic organisms necessarily synthesize not only chlorophylls but also carotenoids. Many kinds of carotenoids are found in algae and, recently, taxonomic studies of algae have been developed. In this review, the relationship between the distribution of carotenoids and the phylogeny of oxygenic phototrophs in sea and fresh water, including cyanobacteria, red algae, brown algae and green algae, is summarized. These phototrophs contain division- or class-specific carotenoids, such as fucoxanthin, peridinin and siphonaxanthin. The distribution of ?-carotene and its derivatives, such as lutein, loroxanthin and siphonaxanthin, are limited to divisions of Rhodophyta (macrophytic type), Cryptophyta, Euglenophyta, Chlorarachniophyta and Chlorophyta. In addition, carotenogenesis pathways are discussed based on the chemical structures of carotenoids and known characteristics of carotenogenesis enzymes in other organisms; genes and enzymes for carotenogenesis in algae are not yet known. Most carotenoids bind to membrane-bound pigment-protein complexes, such as reaction center, light-harvesting and cytochrome b(6)f complexes. Water-soluble peridinin-chlorophyll a-protein (PCP) and orange carotenoid protein (OCP) are also established. Some functions of carotenoids in photosynthesis are also briefly summarized. PMID:21747749

Takaichi, Shinichi

2011-01-01

110

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

111

Settling characteristics of problem algae in the water treatment process.  

PubMed

The settling velocity or removal rates of problem algae in the water treatment process and their flocculants were measured with settling column (SETCOL) and fluorometric method. Our research who were centred on the algal density and shape affecting the settling. The settling velocities of large algae ranged from 0.1 cm/h to 2.6 cm/h, whereas those of small algae were below 1.0 cm/h. The settlings of algae in the stationary growth phase significantly increased and dead algae corresponded with the declining algae. The extent of deformation, which was expressed as the coefficient of form resistance of the algae had the great influences upon the settling. The most extreme deformed algae were needle-shaped ones like Synedra acus, which was known to be a problem in water treatment processes in Korea. Changes in the settling velocity of algae were correlated with algal volume and morphology rather than cell density. PMID:16752771

Choi, S K; Lee, J Y; Kwon, D Y; Cho, K J

2006-01-01

112

Hydrogenases in green algae: do they save the algae's life and solve our energy problems?  

Microsoft Academic Search

Green algae are the only known eukaryotes with both oxygenic photosynthesis and a hydrogen metabolism. Recent physiological and genetic discoveries indicate a close connection between these metabolic pathways. The anaerobically inducible hydA genes of algae encode a special type of highly active [Fe]-hydrogenase. Electrons from reducing equivalents generated during fermentation enter the photosynthetic electron transport chain via the plastoquinone pool.

Thomas Happe; Anja Hemschemeier; Martin Winkler; Annette Kaminski

2002-01-01

113

Estimation of alga growth stage and lipid content growth rate  

NASA Technical Reports Server (NTRS)

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

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

2012-01-01

114

PPR proteins of green algae.  

PubMed

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

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

2013-09-01

115

[Functional components in fish and algae oils].  

PubMed

An important area of the development of new functional foods is facussed on finding or applying food components which favour achieving a healthier lipid profile in the organism. The objective of this work was to carry out the characterisation of the lipid fraction of two oils, fish oil and algae oil, to evaluate their potential use as functional ingredients, in relation to the high molecular weight fatty acid content and the presence of sterols and other components of the unsaponificable fraction. Both oils showed a lipid fraction rich in high molecular weight polyunsaturated omega-3 fatty acids, containing a 33.75% in the fish oil and a 43.97% in the algae oil. Eicosapentaenoic acid was the major fatty acid in fish oil, whereas docosahexaenoic was the most abundant fatty acid in algae oil. The omega-6/omega-3 ratio was lower than 0.4 in both oils. In the unsaponificable fraction, algae oil had a Mold lower cholesterol content and a higher proportion of squalene than fish oil. The phytosterol content was significantly higher in the algae oil. PMID:16771120

Conchillo, A; Valencia, I; Puente, A; Ansorena, D; Astiasar嫕, I

2006-01-01

116

Turning Algae into Energy in New Mexico  

SciTech Connect

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

Sayre, Richard; Olivares, Jose; Lammers, Peter

2013-07-29

117

Algae control problems and practices workshop  

SciTech Connect

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

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

1996-09-01

118

Turning Algae into Energy in New Mexico  

ScienceCinema

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

Sayre, Richard; Olivares, Jose; Lammers, Peter

2014-06-24

119

Genome of the red alga Porphyridium purpureum  

PubMed Central

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.

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

2013-01-01

120

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

121

Purulent pericarditis with greenish pericardial effusion caused by Shewanella algae.  

PubMed

We report the first case of purulent pericarditis with greenish pericardial effusion caused by Shewanella algae in a patient with gastric and gallbladder cancer. This case expands the reported spectrum of infection caused by S. algae and raises the possibility that S. algae is a causative pathogen for purulent pericarditis. PMID:18579719

Tan, Che-Kim; Lai, Chih-Cheng; Kuar, Wei-Khie; Hsueh, Po-Ren

2008-08-01

122

Revision of Cyanidium caldarium. Three species of acidophilic algae  

Microsoft Academic Search

The authors carry out a systematic revision of three unicellular eucaryotic algae, often living in mixed population in thermal acidic environment. Such algae were often confused under the binomium Cyanidium caldarium.The authors state that the following specific binomia are to be attributed to the three algae: Galdieria sulphuraria (Galdieri) Merola comb. nova; Cyanidium caldarium Geitler non (Tilden) Geitler emend.; Cyanidioschyzon

Aldo Merola; Rosa Castaldo; Paolo De Luca; Raffaele Gambardella; Aldo Musacchio; Roberto Taddei

1981-01-01

123

Phosphatase activity of benthic marine algae. An overview  

Microsoft Academic Search

This review provides an account of the phosphatase activities of benthicmarine algae and is based on reports for more than a hundred species, includingcyanobacteria, red, brown and green algae. Particular emphasis is given to theuse of phosphomonoesterase activity as a rapid means of assessing thephosphorusstatus of the alga and thus indirectly that of the environment. Anunderstandingof the influence of environmental

Ignacio Hern嫕dez; F. Xavier Niell; Brian A. Whitton

2002-01-01

124

Modeling and control of algae detachment in regulated canal networks  

Microsoft Academic Search

Algae development in open-channel networks induce major disturbances because of clogging issues on hydraulic devices (pipes, weirs, filters,...). An original strategy to manage these algae developments consists in flushing the fixed algae. The flush is carried out by increasing the hydraulic shear conditions using the hydraulic structures of the canal network. In response to the shear stress increase, a part

Ophelie Fovet; Xavier Litrico; Gilles Belaud

2010-01-01

125

Algae Growth under Combined Conditions of Disturbance, Temperature and Light  

Microsoft Academic Search

Every year since 2003, algae bloom has broken out in the branch bay of the Three Gorges Reservoir in Spring. The area affected by the algae bloom is often subject to disturbance which resulting from shipping, storm-runoff event, water conservancy scheduling and wind-wave etc. With its focus on effect of the disturbances on algae growth, this paper took the Xiangxi

Yu-ling Huang

2010-01-01

126

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.

1980-11-25

127

Purulent Pericarditis with Greenish Pericardial Effusion Caused by Shewanella algae?  

PubMed Central

We report the first case of purulent pericarditis with greenish pericardial effusion caused by Shewanella algae in a patient with gastric and gallbladder cancer. This case expands the reported spectrum of infection caused by S. algae and raises the possibility that S. algae is a causative pathogen for purulent pericarditis.

Tan, Che-Kim; Lai, Chih-Cheng; Kuar, Wei-Khie; Hsueh, Po-Ren

2008-01-01

128

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.

129

Systems and methods for culturing algae with bivalves  

US Patent & Trademark Office Database

Provided herein are systems and methods for extracting lipids and/or producing biofuel from algae in marine and freshwater environments, wherein algae and bivalves are co-cultured in a system of enclosures comprising water that comprises recycled nutrients that are essential for algal growth. The system also include enclosures for culturing fishes which are used to harvest the algae.

2014-06-17

130

Lab 7: Nitrates and Phosphates and Algae, Oh My!  

NSDL National Science Digital Library

Human-induced nutrient loading of the world's oceans has been linked to increased and prolonged algae blooms, sometimes with potentially deadly consequences. In this investigation, students will create their own algal blooms, analyze satellite images of chlorophyll concentrations in the Sea of Cort瀛, and learn about two alarming consequences of excessive algae growth-—dead zones and harmful algae blooms (HABs).

131

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

132

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

133

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

NASA Astrophysics Data System (ADS)

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

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

1993-01-01

134

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

135

Phlorotannins as bioactive agents from brown algae  

Microsoft Academic Search

The importance of food bioactive compounds as functional ingredients has been well recognized due the effectiveness in promoting health and lead to the reduction of disease risk. Especially, nutraceuticals from seaweeds have been served as a rich source of health-promoting components. Among them, marine brown algae are a rich source of natural bioactive compounds, mainly phlorotannins and this fact implies

Yong-Xin Li; Isuru Wijesekara; Yong Li; Se-Kwon Kim

2011-01-01

136

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

137

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

138

Potential of mass algae production in Kuwait  

SciTech Connect

The rationale for efficient light absorption by algae at a production unit is given and design details of an intensive thin-layer technology outdoor (2.11m/sup 2/) unit are presented. Data on productivity under extreme conditions were collected. Maximum productivity data are close to those reported in the literature for similar geographic areas.

Prokop, A.; Fekri, M.

1984-11-01

139

Sequestration of CO2 by halotolerant algae  

PubMed Central

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

2014-01-01

140

Toxicity of atrazine and chlorsulfuron to algae  

Microsoft Academic Search

Sensitivity of three algal species, Chlorella vulgaris, Scenedesmus acutus and Pseudanabaena galeata to herbicides atrazine and chlorsulfuron was studied using single species toxicity tests. Organisms were exposed to different concentrations of these herbicides and the algal growth was measured by turbidity at 750 nm. Atrazine appeared to be the most inhibitory to algae growth. 96 hr EbC50 of atrazine was:

J. M. Carrasco; C. Sabater

1997-01-01

141

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...

142

Biogeochemistry: Ancient algae crossed a threshold  

NASA Astrophysics Data System (ADS)

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

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

2013-08-01

143

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

144

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

2013-05-01

145

Bioconcentration of tetrachlorobenzene in marine algae  

NASA Astrophysics Data System (ADS)

Bioconcentration of tetrachlorobenzene (TeCB) in Chlorella marine, Nannochloropsis oculata, Pyramidomonas sp., Platymonas subcordiformis, and Phaeodactylum tricornutum; and toxicity of TeCB to the marine algae were tested. Values of bioconcentration potential parameters, including uptake rate constant k 1, elimination rate constant k 2 and bioconcentration factor BCF, were obtained not only from the time course of TeCB uptake by the marine algae by using a bioconcentration model, but also from the acute toxicity test data for percent inhibition PI(%)exposure concentration of TeCB-time by using a combined bioconcentration and probability model. The results showed good relationship between k 1(TOXIC) and k 1(UPTAKE) and k 2(TOXIC), k 2(UPTAKE), and BCF D(IOXIC) and BCF D(UPTAKE). Especially, the values of BCF D(TOXIC) were well consistent with those of BCF D(UPTAKE).

Wang, Xiu-Lin; Ma, Yan-Jun; Cheng, Gang; Yu, Wei-Jun; Zhang, Li-Jun

1997-09-01

146

Toxicity of chlorinated benzenes to marine algae  

NASA Astrophysics Data System (ADS)

Growth of Chlorella marine, Nannochloropsis oculata, Pyramidomonas sp., Platymonas subcordiformis and Phaeodactylum tricornutum exposed to monochlorobenzene (MCB), 1,2-dichlorobenzene (1,2-DCB), 1, 2, 3, 4-tetrachlorobenzene (1, 2, 3, 4-TeCB) and pentachlorobenzene (PeCB) was tested. Tests of 72 h- EC 50 values showed that the toxicity ranged in the order: MCB<1,2-DCB<1,2,3,4-TeCBalgae was almost in the order: Pyramidomonas sp. < Platymonas subcordiformis < Nannochloropsis oculata < Chlorella marine < Phaeodactylum tricomutum. Study of the QSAR (Quantitative Structure-Activity Relationship) between K OW and toxicity of CBs to marine algae showed good relationships between -log EC 50 and log K OW.

Ma, Yan-Jun; Wang, Xiu-Lin; Yu, Wei-Jun; Zhang, Li-Jun; Sun, Han-Zhang

1997-12-01

147

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

148

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

149

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

150

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

2013-01-01

151

Prokaryotic algae associated with Australian proterozoic stromatolites.  

NASA Technical Reports Server (NTRS)

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

Licari, G. R.; Cloud, P.

1972-01-01

152

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

153

Studies on polyethers produced by red algae.  

PubMed

Two novel squalene-derived triterpenes, spirodehydrovenustatriol (3) and 14-keto-dehydrothyrsiferol (4) were isolated from the red alga Laurencia viridis, together with two new and unusual C(17) terpenoids, adejen A (5) and B (6). These truncated structures possess structural similarities with other known squalene metabolites and their biogenetic origin has been proposed on the basis of an oxidative process of the squalene skeleton. All the structures were elucidated by extensive use of 2D NMR spectroscopic methods. PMID:20479973

Cen-Pacheco, Francisco; Nordstr闣, Laurette; Souto, Mar燰 Luisa; Mart璯, Manuel Norte; Fern嫕dez, Jos Javier; Daranas, Antonio Hern嫕dez

2010-01-01

154

Blue-green algae toxicosis in cattle.  

PubMed

Twenty-four of 175 heifers died after ingesting water from a stock pond containing blue-green algae (genus Microcystis) in southern Colorado. Affected cattle were found dead or had signs of nervousness, and were recumbent, weak, anorectic, and hypersensitive to noise when first examined. All cattle died within 3 days after the onset of signs. At necropsy, the rumen contained blue-green algae, and the liver was larger than normal, friable, and dark red. The most important histologic lesion was hepatocyte degeneration and necrosis. Intraperitoneal administration of lyophilized cell material from the bloom caused hepatic necrosis and death in mice, and water from the pond had clumps of cells surrounded by a clear calyx, consistent with the appearance of organisms of the genus Microcystis. Samples of pond water were examined by means of high-pressure liquid chromatography; microcystin-LR, one of the hepatotoxins produced by Microcystis spp, was found. Chromatography may be useful in the diagnosis of blue-green algae toxicosis. PMID:9838962

Puschner, B; Galey, F D; Johnson, B; Dickie, C W; Vondy, M; Francis, T; Holstege, D M

1998-12-01

155

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

Microsoft Academic Search

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

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

1989-01-01

156

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

157

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

158

[The efficiency of algae removal from drinking water by ferrate].  

PubMed

This paper studied the efficiency of algae removal by ferrate from two kinds of raw water which were collected from Donghu and Tiegang reservoir respectively. The experimental results showed that the removal efficiency of algae reached about 95% only through PAC coagulation when the raw water was extracted from Donghu reservoir in which most of algae was Chlorella. But dealing with Tiegang raw water in which the majority of algae were Oscillatoria, terrate was used as pre-oxidant coupling with PAC coagulation not only using PAC to flocculate and the efficiency of algae removal could be up to 97.85%. However this treatment method using ferrate as pre-oxidant overmatched the traditional method prechlorination for algae removal. PMID:11432074

Yuan, B; Qu, J; Zhang, J; Ge, X; Liang, M; Tian, B

2001-03-01

159

Biology and systematics of heterokont and haptophyte algae.  

PubMed

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

Andersen, Robert A

2004-10-01

160

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

161

Cobra bite wound infection caused by Shewanella algae.  

PubMed

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

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

2014-03-01

162

Saturated and unsaturated hydrocarbons in marine benthic algae  

Microsoft Academic Search

Saturated and olefinic hydrocarbons were determined in 24 species of green, brown and red benthic marine algae from the Cape Cod area (Massachusetts, USA). Among the saturated hydrocarbons, n-pentadecane predominates in the brown and n-heptadecane in the red algae. A C17 alkyleyclopropane has been identified tentatively in Ulvalactuca and Enteromorpha compressa, two species of green algae. Mono-and diolefinic C15 and

W. W. Youngblood; M. Blumer; R. L. Guillard; F. Fiore

1971-01-01

163

Effect of pesticides on blue-green algae  

Microsoft Academic Search

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

P. K. Singh

1973-01-01

164

Method for producing hydrogen and oxygen by use of algae  

DOEpatents

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

Greenbaum, E.

1982-06-16

165

Algae to Bio-Crude in Less Than 60 Minutes  

SciTech Connect

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

Elliott, Doug

2013-12-17

166

Algae to Bio-Crude in Less Than 60 Minutes  

ScienceCinema

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

Elliott, Doug

2014-06-02

167

Method for producing hydrogen and oxygen by use of algae  

DOEpatents

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

Greenbaum, Elias (Oak Ridge, TN)

1984-01-01

168

The exploitation of beds of green algae by brent geese  

NASA Astrophysics Data System (ADS)

Brent geese on the Norfolk coast occurred on beds of green algae (primarily Enteromorpha spp.) at low tide during autumn and early winter. Feeding was the main activity. Numbers of geese started to decline when the biomass of algae had fallen to c. 5 g dry wt m -2, and the birds rarely occurred on the beds after the biomass had reached c. 1 g dry wt m -2 in late November. The biomass of ungrazed algae did not decline as rapidly, nor to as low a level as that of grazed algae during the winter, showing that grazing by geese was partly responsible for the earlier decline in this food source.

Summers, Ronald W.

1990-07-01

169

Method and apparatus for lysing and processing algae  

DOEpatents

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

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

2013-03-05

170

Algae Bioreactor Using Submerged Enclosures with Semi-Permeable Membranes  

NASA Technical Reports Server (NTRS)

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

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

2013-01-01

171

Estudo radiocientico em algas marinhas bentonicas. (Radiokinetic study in benthic marine algae).  

National Technical Information Service (NTIS)

The influx and outflux kinetics of some radionuclides in algae of the Rio de Janeiro coastline, were studied in order to select bioindicators for radioactive contamination in aquatic media, due to the presence of Nuclear Power Stations. Bioassays of the c...

V. Azevedo Gouvea

1981-01-01

172

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

173

Steroids from green alga Chaetomorpha basiretorsa Setchell  

NASA Astrophysics Data System (ADS)

Six steroids have been isolated from ethanolic extract of green alga Chaetomorpha basiretorsa Setchell by a combination of repeated normal phase silica gel and Sephadex LH-20 gel column chromatography as well as recrystallization. Using spectroscopic methods including MS and NMR, their structures were determined as ?-lawsaritol (1), saringosterol (2), 24-hydroperoxy-24-vinyl-cholesterol (3), ?-stigmasterol (4), stigmast-4-en-3?, 6?-diol (5), 29-hydroxystigmasta-5, 24 (28)-dien-3?-ol (6). All these compounds were obtained from this genus for the first time and they were inactive (IC50>10 ?g /ml) against KB, Bel-7402, PC-3M, Ketr 3 and MCF-7 cell lines.

Shi, Dayong; Fan, Xiao; Sun, Jie; Han, Lijun; Shi, Jiangong

2008-11-01

174

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

175

First case of osteomyelitis due to Shewanella algae.  

PubMed

Shewanella spp. are infrequently recovered from clinical specimens. We report here on the first case of osteomyelitis due to Shewanella algae. This bacterium, at first misidentified by phenotypic tests as Shewanella putrefaciens, was subsequently identified correctly as S. algae by 16S rRNA gene sequence analysis. PMID:16208026

Botelho-Nevers, E; Gouriet, F; Rovery, C; Paris, P; Roux, V; Raoult, D; Brouqui, P

2005-10-01

176

Copper Tolerance in the Marine Fouling Alga Ectocarpus siliculosus  

Microsoft Academic Search

INTRASPECIFIC variation in marine algae in response to habitat conditions has been proposed1 and, in some cases2,3, demonstrated. During an investigation into the ship-fouling properties of the brown alga Ectocarpus siliculosus (Dillw.) Lyngb. we have found evidence of differential response to dissolved copper which may be associated with the habitats from which the populations were taken.

G. Russell; O. P. Morris

1970-01-01

177

Potential pharmacological applications of polyphenolic derivatives from marine brown algae  

Microsoft Academic Search

Recently, the isolation and characterization of the biologically active components from seaweeds have gained much attention from various research groups across the world. The marine algae have been studied for biologically active components and phlorotannins are one among them. Among marine algae, brown algal species such as Ecklonia cava, Eisenia arborea, Ecklonia stolinifera and Eisenia bicyclis have been studied for

Noel Vinay Thomas; Se-Kwon Kim

2011-01-01

178

Bacteriostatic effects of some algae- and lemna minor extracts  

Microsoft Academic Search

1.In some stages of their development the algae Spirogyra sp. and Euglena viridis contain in their cells bacteriostatic substances that have a reducing influence upon the growth of Sphaerotilus natans, Bacillus mycoides and Leptothrix ochracea. The extract of these algae were found to have no bacteriostatic effect upon Escherichia coli, Sarcina lutea and Staphylococcus aureus.2.In relation to all above mentioned

Marian Stangenberg

1968-01-01

179

Interactions of Algae within the Community of Gracilaria gracilis (Rhodophyta)  

Microsoft Academic Search

Interactions among the unattached red alga Gracilaria gracilis, the dominant species of an algal community, and associated algal species Chaetomorpha linum, Enteromorpha prolifera f. prolifera, and Polysiphonia sp. were studied during and after an algal bloom. It was shown that during their bloom the associated algae Enteromorpha and Polysiphonia sp. significantly decreased the photosynthetic rate of G. gracilis but did

Yu. V. Nabivailo; A. V. Skriptsova; E. A. Titlyanov

2005-01-01

180

Blue-Green Algae and Freshwater Carbonate Deposits  

Microsoft Academic Search

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

A. Pentecost

1978-01-01

181

Photoreversible Pigment: Occurrence in a Blue-Green Alga  

Microsoft Academic Search

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

Joseph Scheibe

1972-01-01

182

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

183

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

184

Photosynthesis, photorespiration, and dark respiration in eight species of algae  

Microsoft Academic Search

The rates of photosynthesis and dark respiration for 7 marine algae and 1 fresh-water alga were measured and compared. The dinoflagellates Glenodinium sp. and zooxanthellae have high dark respiration rates relative to photosynthetic rates, which may decrease their net growth rates. Photorespiration in the 8 algal species was studied by examining the effects of the concentration of oxygen on the

J. E. Burris

1977-01-01

185

Coral Endolithic Algae: Life in a Protected Environment  

Microsoft Academic Search

Endolithic algae inhabiting skeletons of living corals appear to be adapted to an extreme environment created by the coral. However, measurements on three coral species from the genus Porites revealed that these corals provide several modes of protection to the algae as well. High concentrations of ultraviolet (UV)-absorbing compounds, mycosporine-like amino acids (MAAs), were found in the tissues of all

N. SHASHAR; A. T. BANASZAK; M. P. LESSER; D. AMRAMI

186

Iron acquisition and allocation in stramenopile algae.  

PubMed

The essential element iron has a low biological availability in the surface ocean where photosynthetic organisms live. Recent advances in our understanding of iron acquisition mechanisms in brown algae and diatoms (stramenopile algae) show the importance of the reduction of ferric to ferrous iron prior to, or during, transport in the uptake process. The uses of iron in photosynthetic stramenopiles resembles that in other oxygenic organisms, although (with the exception of the diatom Thalassiosira oceanica from an iron-deficient part of the ocean) they lack plastocyanin, instead using cytochrome c 6, This same diatom further economizes genotypically on the use of iron in photosynthesis by decreasing the expression of photosystem I, cytochrome c 6, and the cytochrome b 6 f complex per cell and per photosystem II relative to the coastal Thalassiosira pseudonana; similar changes occur phenotypically in response to iron deficiency in other diatoms such as Phaeodactylum tricornutum. In some diatoms grown under iron-limiting conditions, essentially all of the iron in the cells can be accounted for by the iron occurring in catalytic proteins. However, stramenopiles can store iron. Genomic studies show that pennate, but not centric, diatoms have the iron storage protein ferritin. While M飉sbauer and X-ray analysis of (57)Fe-labelled Ectocarpus siliculosus shows iron in an amorphous mineral phase resembling the core of ferritin, the genome shows no protein with significant sequence similarity to ferritin. PMID:23658428

Raven, John A

2013-05-01

187

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

188

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

189

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

190

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

191

Spectral optical properties of selected photosynthetic microalgae producing biofuels  

NASA Astrophysics Data System (ADS)

This paper presents the spectral complex index of refraction of biofuel producing photosynthetic microalgae between 400 and 750 nm. They were retrieved from their experimentally measured average absorption and scattering cross-sections. The microalgae were treated as homogeneous polydisperse spheres with equivalent diameter such that their surface area was identical to that of their actual spheroidal shape. An inverse method was developed combining Lorentz-Mie theory as the forward method and genetic algorithm. The unicellular green algae Chlamydomonas reinhardtii strain CC125 and its truncated chlorophyll antenna transformants tla1, tlaX, and tla1-CW+ as well as Botryococcus braunii, Chlorella sp., and Chlorococcum littorale were investigated. These species were selected for their ability to produce either hydrogen gas or lipids for liquid fuel production. Their retrieved real and imaginary parts of the complex index of refraction were continuous functions of wavelength with absorption peaks corresponding to those of in vivo Chlorophylls a and b. The T-matrix method was also found to accurately predict the experimental measurements by treating the microalgae as axisymmetric spheroids with the experimentally measured major and minor diameter distributions and the retrieved spectral complex index of refraction. Finally, pigment mass fractions were also estimated from the retrieved absorption index. The method and/or the reported optical properties can be used in various applications from ocean remote sensing, carbon cycle study, as well as photobiological carbon dioxide mitigation and biofuel production.

Lee, Euntaek; Heng, Ri-Liang; Pilon, Laurent

2013-01-01

192

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

193

Shewanella algae: A Rare Cause of Necrotizing Fasciitis.  

PubMed

Abstract Background: The genus Shewanella consists of motile, gram-negative, facultative anaerobes found in marine environments. Shewanella putrefaciens and Shewanella algae are the two species with documented pathogenicity in human beings. Most documented cases of S. algae infection worldwide have been reported in the context of bacteremia, cellulitis, and acute exacerbations of chronic otitis media in predisposed individuals. We report a rare case of necrotizing soft tissue infection by S. algae in an immunocompetent individual. The infection followed exposure to S. algae in contaminated water in New York City, New York. Methods: We reviewed the English-language literature on similar cases of soft tissue infection using PubMed. Search terms included "Shewanella algae" and "Shewanella putrefaciens" in conjunction with "necrotizing" and "infection." Cognizant that this search method may not have yielded early (pre-1985) reports about Shewanella because of changes in classification and nomenclature, we also searched for "Pseudomonas putrefaciens." Results: After prompt surgical debridement and culture-directed antibiotic therapy, the patient recovered from his infection without the need for re-intervention. Conclusions: This case may reflect the geographic spread and emergence of S. algae infection in the United States. Clinicians should be aware of the virulence of S. algae and potential for the rapid clinical deterioration of persons it infects even among immunocompetent individuals. PMID:24116855

Ananth, Aditi L; Nassiri, Naiem; Pamoukian, Vicken N

2014-06-01

194

Ecology of bottom ice algae: III. Comparative physiology  

NASA Astrophysics Data System (ADS)

The physiological behavior of bottom ice algal assemblages has been studied intensively at several locations, particularly over the last decade. Ice algal populations can be studied for 1-3 months because they are stationary and their environmental conditions can also be manipulated in situ. Therefore, they present a model system for studies of the physiological ecology of natural microalgal populations. Physiological responses to major environmental variables, including temperature, salinity, irradiance and nutrients, have been characterized. Ice algae are physiologically similar to polar phytoplankton, but there are important differences which appear to reflect their respective environmental conditions. Photosynthesis vs. irradiance responses, photosynthate allocation and biochemical composition have been determined for vernal blooms. Ice algae and phytoplankton have similar gross biochemical compositions (e.g., C:N, C:Si, C:Chl), but lipid contents can be markedly higher in ice algae. Ice algae normally exhibit relatively low maximal assimilation numbers (except at subpolar latitudes) but markedly higher photosynthetic efficiencies than planktonic diatoms; large low frequency fluctuations in photosynthetic performance are common during the later phases of blooms. Ice algae have relatively low photoadaptive indices Ik and optimal irradiances Im, reflecting their average growth irradiance. Compared to phytoplankton, photosynthate allocation by ice algae is lower for protein, similar for lipid but higher for polysaccharide and metabolites at the same irradiance. In several respects the physiological behavior of ice algae appears to be fundamentally different than that of phytoplankton.

Cota, Glenn F.; Smith, Ralph E. H.

1991-08-01

195

Random flow induced by swimming algae  

NASA Astrophysics Data System (ADS)

In this work we studied the random flow induced in a fluid by the motion of a dilute suspension of the swimming algae Volvox carteri. The fluid velocity in the suspension is a superposition of the flow fields set up by the individual organisms, which in turn have multipole contributions that decay as inverse powers of distance from the organism. Here we show that the conditions under which the central limit theorem guarantees a Gaussian probability distribution function of velocity fluctuations are satisfied when the leading force singularity is a Stokeslet. Deviations from Gaussianity are shown to arise from near-field effects. Comparison is made with the statistical properties of abiotic sedimenting suspensions. The experimental results are supplemented by extensive numerical studies.

Kantsler, Vasily; Rushkin, Ilia; Goldstein, Raymond

2010-11-01

196

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

197

An algae-covered alligator rests warily  

NASA Technical Reports Server (NTRS)

An algae-covered alligator keeps a wary eye open as it rests in one of the ponds at Kennedy Space Center. American alligators feed and rest in the water, and lay their eggs in dens they dig into the banks. The young alligators spend their first several weeks in these dens. The Center shares a boundary with the Merritt Island National Wildlife Refuge, which encompasses 92,000 acres that are a habitat for more than 331 species of birds, 31 mammals, 117 fishes, and 65 amphibians and reptiles. The marshes and open water of the refuge provide wintering areas for 23 species of migratory waterfowl, as well as a year-round home for great blue herons, great egrets, wood storks, cormorants, brown pelicans and other species of marsh and shore birds, as well as a variety of insects.

2000-01-01

198

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

199

Biological activities and potential health benefits of sulfated polysaccharides derived from marine algae  

Microsoft Academic Search

Recently, a great deal of interest has been developed to isolate novel bioactive compounds from marine resources because of their numerous health beneficial effects. Among marine resources, marine algae are valuable sources of structurally diverse bioactive compounds. The cell walls of marine algae are rich in sulfated polysaccharides (SPs) such as fucoidans in brown algae, carrageenans in red algae and

Isuru Wijesekara; Ratih Pangestuti; Se-Kwon Kim

2011-01-01

200

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

201

Detection of green algae (Chlorophyceae) for the diagnosis of drowning.  

PubMed

The plankton test (generally, diatom test) is one of the methods available to diagnose the cause of death of submerged bodies. The solubilization method using tissue solubilizer Soluene-350 was used in this study to detect not only diatoms but also green algae, based on the fact that the solubilizer does not digest the cell walls of green algae which are made from cellulose. Detection of green algae from organs of submerged cadavers is very informative to determine drowning in fresh water, and also in cases where only few diatoms are detected in the organs. PMID:7495686

Yoshimura, S; Yoshida, M; Okii, Y; Tokiyasu, T; Watabiki, T; Akane, A

1995-01-01

202

Viable Cyanobacteria and Green Algae from the Permafrost Darkness  

SciTech Connect

This review represents an overview of the existence, distribution and abundance of the photoautotrophic microorganisms in the deep subsurface permafrost of the Northeast Russia and McMurdo Dry Valleys, Antarctica. The morphology, growth rate, spectral properties, phylogenetic position of the viable permafrost green algae and cyanobacteria have been studied. Viable photoautotrophs were represented by unicellular green algae and filamentous cyanobacteria with low growth rate. Spectral studies of ancient cyanobacteria and green algae did not reveal any significant differences between them and their contemporary relatives. Phylogenetic analyses have shown that permafrost photoautotrophs were closely related to strains and more often to uncultured environmental clones from cold regions.

Vishnivetskaya, Tatiana A [ORNL

2009-01-01

203

University of Texas-Austin: The Culture Collection of Algae  

NSDL National Science Digital Library

Housed at the University of Texas-Austin, The Culture Collection of Algae "includes over 2,300 different strains of living algae, representing most major algal taxa. The primary function of UTEX is to provide algal cultures at modest cost to a user community." The cultures are generally utilized for teaching, research, and biotechnology development. Site visitors will find an online catalogue of cultures organized alphabetically by class and by genus. UTEX provides an order form, as well as ordering and purchasing information. The site also provides a six-page list of literature references; links to other online algae collections; an image gallery; and notes on culture maintenance and growth media.

204

CONTROL TECHNOLOGY EXTRACTION OF MERCURY FROM GROUNDWATER IMMOBILIZED ALGAE  

EPA Science Inventory

Bio-Recovery Systems, Inc. conducted a project under the Emerging Technology portion of the United States Environmental Protection Agency (EPAs) Superfund Innovative Technology Evaluation (SITE) Program to evaluate the ability of immobilized algae to adsorb mercury from contamina...

205

Uptake of Glycine by Blue-Green Algae.  

National Technical Information Service (NTIS)

Uptake of glycine-14C was measured in 3 species of blue-green algae, viz Oscillatoria jasorvensis, Gloeotrichia pisum and Microcystis aeruginosa. Radioactivity in breis of Oscillatoria increased with increasing time of incubation in glycine-14C solution. ...

G. C. Stephens B. S. Vaidya O. P. Saxena

1968-01-01

206

Harmful algae blooms removal from fresh water with modified vermiculite.  

PubMed

Vermiculite and vermiculite modified with hydrochloric acid were investigated to evaluate their flocculation efficiencies in freshwater containing harmful algae blooms (HABs) (Microcystis aeruginosa). Scanning electron microscope, Fourier transform infrared spectroscopy, X-ray diffraction, converted fluorescence microscope, plasma-atomic emission spectrometry, and Zetasizer were used to study the flocculation mechanism of modified vermiculite. It was found that the vermiculite modified with hydrochloric acid could coagulate algae cells through charge neutralization, chemical bridging, and netting effect. The experimental results show that the efficiency of flocculation can be notably improved by modified vermiculite. Ninety-eight per cent of algae cells in algae solution could be removed within 10 min after the addition ofmodified vermiculite clay. The method that removal of HABs with modified vermiculite is economical with high efficiency, and more research is needed to assess their ecological impacts before using in practical application. PMID:24600873

Miao, Chunguang; Tang, Yi; Zhang, Hong; Wu, Zhengyan; Wang, Xiangqin

2014-01-01

207

Potential pharmacological applications of polyphenolic derivatives from marine brown algae.  

PubMed

Recently, the isolation and characterization of the biologically active components from seaweeds have gained much attention from various research groups across the world. The marine algae have been studied for biologically active components and phlorotannins are one among them. Among marine algae, brown algal species such as Ecklonia cava, Eisenia arborea, Ecklonia stolinifera and Eisenia bicyclis have been studied for their potential biological activities. Majority of the investigations on phlorotannins derived from brown algae have exhibited their potentiality as antioxidant, anti-inflammatory, antidiabetic, antitumor, antihypertensive, anti-allergic, hyaluronidase enzyme inhibition and in matrix metalloproteinases (MMPs) inhibition activity. In this review, we have made an attempt to discuss the potential biological activities of phlorotannins from marine brown algae and their possible candidature in the pharmaceutical applications. PMID:22004951

Thomas, Noel Vinay; Kim, Se-Kwon

2011-11-01

208

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 ...

209

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

210

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 ...

211

Nutrient Transformations in Mass Cultures of Marine Algae.  

National Technical Information Service (NTIS)

The report presents a novel concept for controlling the discharge of wastewater-borne nutrients (primarily nitrogen) into coastal marine waters. The process, called 'controlled eutrophication,' involves, the regulated assimilation of nutrients by algae in...

J. C. Goldman J. H. Ryther

1974-01-01

212

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

213

Algae Reefs in Shark Bay, Western Australia, Australia  

NASA Technical Reports Server (NTRS)

Numerous algae reefs are seen in Shark Bay, Western Australia, Australia (26.0S, 113.5E) especially in the southern portions of the bay. The south end is more saline because tidal flow in and out of the bay is restricted by sediment deposited at the north and central end of the bay opposite the mouth of the Wooramel River. This extremely arid region produces little sediment runoff so that the waters are very clear, saline and rich in algae.

1990-01-01

214

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

215

Studies on nitrogen fixation by blue-green algae  

Microsoft Academic Search

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

P. Fay; G. E. Fogg

1962-01-01

216

Nitrogen fixation by unicellular blue-green algae  

Microsoft Academic Search

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

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

1971-01-01

217

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

Microsoft Academic Search

Unicellular green algae have the ability to operate in two distinctly different environments (aerobic and anaerobic), and\\u000a to photosynthetically generate molecular hydrogen (H2). A recently developed metabolic protocol in the green alga Chlamydomonas reinhardtii permitted separation of photosynthetic O2-evolution and carbon accumulation from anaerobic consumption of cellular metabolites and concomitant photosynthetic H2-evolution. The H2 evolution process was induced upon sulfate

Anastasios Melis

2007-01-01

218

Association between exudates of brown algae and polychlorinated biphenyls  

Microsoft Academic Search

Exudates from the brown algaeCaepidium antarcticum andDesmarestia sp. were investigated for their ability to associate with hydrophobic pollutants such as polychlorinated biphenyls (PCB s).\\u000a The percentage of PCB associated with algal exudates ranged from 79% for decachlorobiphenyl to 23% for the pentachlorobiphenyl\\u000a congener No. 95. Exudates from the tested brown algae may therefore alter the bioavailability of PCBs in natural

R. J. Lara; C. Wiencke; W. Ernst

1989-01-01

219

A review of heavy metal adsorption by marine algae  

Microsoft Academic Search

Accumulation of heavy metals by algae had been studied extensively for biomonitoring or bioremediation purposes. Having the\\u000a advantages of low cost raw material, big adsorbing capacity, no secondary pollution, etc., algae may be used to treat industrial\\u000a water containing heavy metals. The adsorption processes were carried out in two steps: rapid physical adsorption first, and\\u000a then slow chemical adsorption. pH

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

2000-01-01

220

Algae biodiesel has potential despite inconclusive results to date  

Microsoft Academic Search

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

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

221

Effect of ultrasonic frequency and power on algae suspensions.  

PubMed

Cyanobacteria are photosynthetic bacteria with some characteristics of algae. Some cyanobacteria produce toxins that have been shown to be hazardous to both animals and humans. Previous research has demonstrated power ultrasound can provide a suitable method to control algae blooms although the optimum ultrasonic parameter settings have not been determined to ensure an effective and energy efficient treatment. In this work the effect of ultrasound on suspensions of Microcystis aeruginosa has been investigated at the following frequencies 20, 40, 580, 864 and 1146 kHz. Results showed that the reduction in algal numbers is dependent on both frequency and intensity. In order to quantify the effect we have defined the efficiency of the ultrasonic control of algae at a specific frequency as: (% inactivation of the algae) / (ultrasonic intensity applied). When this is applied to the results at different frequencies the order of efficiency for algae reduction is 20 < 1146 < 864 < 580 kHz. This suggests that ultrasound can offer a suitable method for algae inactivation or control but the sonication conditions must be taken into account. PMID:20401779

Joyce, Eadaoin M; Wu, Xiaoge; Mason, Timothy J

2010-01-01

222

[Simulation of algae bloom under different flow velocity].  

PubMed

The construction of a river-type reservoir will normally cause a change of hydrodynamic condition and a decrease of flow velocity in branch bays, leading to the formation of algae bloom when appropriate environmental conditions and sufficient nutrient supply are encountered, and thereby, causing the deterioration of fluvial ecosystem therein. To investigate the effects of hydrodynamic conditions on algae bloom, flow velocity was taken as the characteristic parameter, and controlled differently in the closed and recurrent models under identical environmental and nutrient conditions. The results showed that the increase of the flow velocity in a range of < 0. 4 m x s(-1) would accelerate the growth of algae and the occurrence of bloom. Under the conditions of different flow velocity, the growth of algae was similar to the common process of other microorganisms, namely, lag phase firstly, exponential phase secondly, stationary phase thirdly, and decline phase lastly. Accordingly, the outbreak peak and regression floor of the algae bloom would occur. Therefore, the increase of flow velocity in a range of < 0. 4 m x s(-1) would not inhibit the growth of algae and the occurrence of bloom. The effective characteristic parameter of the hydrodynamic conditions would be studied in depth in future. PMID:19123369

Huang, Yu-Ling; Liu, De-Fu; Chen, Ming-Xi

2008-10-01

223

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

224

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

225

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

226

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

227

Phosphorus-limited growth of a green alga and a blue-green alga  

SciTech Connect

The phosphorus-limited growth kinetics of the chlorophyte Scenedesmus quadricauda and the cyanophyte Synechococcus Nageli were studied by using batch and continuous culturing techniques. The steady-state phosphate transport capability and the phosphorus storage capacity is higher in S. Nageli than in S. quadricauda. Synechococcus Nageli can also deplete phosphate to much lower levels than can S. quadricauda. These results, along with their morphological characteristics, were used to construct partial physiological profiles for each organism. The profiles indicate that this unicellular cyanophyte (cyanobacterium) is better suited for growth in phosphorus-limited oligotrophic niches than is this chlorophyte (green alga). (Refs. 44).

Lang, D.S.; Brown, E.J.

1981-12-01

228

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

Microsoft Academic Search

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

Martin M. Kulik

1995-01-01

229

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

2011-09-01

230

News about cryptochrome photoreceptors in algae.  

PubMed

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

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

2013-02-01

231

Comparative Transcriptome Analysis of Four Prymnesiophyte Algae  

PubMed Central

Genomic studies of bacteria, archaea and viruses have provided insights into the microbial world by unveiling potential functional capabilities and molecular pathways. However, the rate of discovery has been slower among microbial eukaryotes, whose genomes are larger and more complex. Transcriptomic approaches provide a cost-effective alternative for examining genetic potential and physiological responses of microbial eukaryotes to environmental stimuli. In this study, we generated and compared the transcriptomes of four globally-distributed, bloom-forming prymnesiophyte algae: Prymnesium parvum, Chrysochromulina brevifilum, Chrysochromulina ericina and Phaeocystis antarctica. Our results revealed that the four transcriptomes possess a set of core genes that are similar in number and shared across all four organisms. The functional classifications of these core genes using the euKaryotic Orthologous Genes (KOG) database were also similar among the four study organisms. More broadly, when the frequencies of different cellular and physiological functions were compared with other protists, the species clustered by both phylogeny and nutritional modes. Thus, these clustering patterns provide insight into genomic factors relating to both evolutionary relationships as well as trophic ecology. This paper provides a novel comparative analysis of the transcriptomes of ecologically important and closely related prymnesiophyte protists and advances an emerging field of study that uses transcriptomics to reveal ecology and function in protists.

Koid, Amy E.; Liu, Zhenfeng; Terrado, Ramon; Jones, Adriane C.; Caron, David A.; Heidelberg, Karla B.

2014-01-01

232

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

2010-11-01

233

Shewanella algae and Shewanella putrefaciens: clinical and microbiological characteristics.  

PubMed

The occurrence of the two Shewanella species found in clinical specimens, Shewanella algae and Shewanella putrefaciens, correlates with the temperature and salinity of seawater. This means that Shewanella infections occur in warm climates or during especially warm summers in temperate climates. The infections described most commonly involve ears, skin and soft tissue, with or without bacteraemia. Primary bacteraemia with a fulminant course is also seen in immunocompromised patients. Important differential characteristics between the two species include the ability of S. algae to produce mucoid colonies with beta-haemolysis on sheep blood agar, to grow at 42 degrees C and in NaCl 6% w/v, and to reduce nitrite, and an inability to produce acid from maltose, all of which are in contrast to the characteristics of S. putrefaciens. Automated identification systems fail to differentiate between S. algae and S. putrefaciens, as S. algae is not included in the databases of these systems. Presumably for this reason, most Shewanella infections reported during recent years have been attributed to S. putrefaciens. However, when extensive phenotypic characterisation is performed, most human infections are seen to be caused by S. algae. As the two species seem to have different pathogenic potential for humans, correct identification is important, and this is possible in routine clinical microbiology laboratories. PMID:15819859

Holt, H M; Gahrn-Hansen, B; Bruun, B

2005-05-01

234

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

2010-09-01

235

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

2011-01-01

236

Influence of algae on photolysis rates of chemicals in water  

SciTech Connect

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

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

1983-08-01

237

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

238

Mg-lattice associations in red coralline algae  

NASA Astrophysics Data System (ADS)

Recent investigations have shown red coralline algae to record ambient temperature in their calcite skeletons. Temperature recorded by variation in Mg concentrations within algal growth bands has sub-annual resolution and high accuracy. The conversion of Mg concentration to temperature is based on the assumption of Ca replacement by Mg within the algal calcite skeleton at higher temperatures. While Mg-temperature relationships in coralline algae have been calibrated for some species, the location of Mg within the calcite lattice remains unknown. Critically, if Mg is not a lattice component but associated with organic components this could lead to erroneous temperature records. Before coralline algae are used in large scale climate reconstructions it is therefore important to determine the location of Mg. Synchrotron Mg-X-ray absorbance near edge structure (XANES) indicates that Mg is associated with the calcite lattice in Lithothamnion glaciale (contemporary free-living, contemporary encrusting and sub-fossil free-living) and Phymatolithon calcareum (contemporary free-living) coralline algae. Mg is deposited within the calcite lattice in all seasons (L. glaciale & P. calcareum) and thallus areas (P. calcareum). These results suggest L. glaciale and P. calcareum are robust Mg-palaeotemperature proxies. We suggest that similar confirmation be obtained for Mg associations in other species of red coralline algae aiding our understanding of their role in climate reconstruction at large spatial scales.

Kamenos, N. A.; Cusack, M.,; Huthwelker, T.; Lagarde, P.; Scheibling, R. E.

2009-04-01

239

Mg-lattice associations in red coralline algae  

NASA Astrophysics Data System (ADS)

Recent investigations have shown red coralline algae to record ambient temperature in their calcite skeletons. Temperature recorded by variation in Mg concentrations within algal growth bands has sub-annual resolution and high accuracy. The conversion of Mg concentration to temperature is based on the assumption of Ca replacement by Mg within the algal calcite skeleton at higher temperatures. While Mg-temperature relationships in coralline algae have been calibrated for some species, the location of Mg within the calcite lattice remains unknown. Critically, if Mg is not a lattice component but associated with organic components this could lead to erroneous temperature records. Before coralline algae are used in large scale climate reconstructions it is therefore important to determine the location of Mg. Synchrotron Mg-X-ray absorbance near edge structure (XANES) indicates that Mg is associated with the calcite lattice in Lithothamnion glaciale (contemporary free-living, contemporary encrusting and sub-fossil free-living) and Phymatolithon calcareum (contemporary free-living) coralline algae. Mg is deposited within the calcite lattice in all seasons ( L. glaciale & P. calcareum) and thallus areas ( P. calcareum). These results suggest L. glaciale and P. calcareum are robust Mg-palaeotemperature proxies. We suggest that similar confirmation be obtained for Mg associations in other species of red coralline algae aiding our understanding of their role in climate reconstruction at large spatial scales.

Kamenos, N. A.; Cusack, M.; Huthwelker, T.; Lagarde, P.; Scheibling, R. E.

2009-04-01

240

Method to transform algae, materials therefor, and products produced thereby  

DOEpatents

Disclosed is a method to transform chlorophyll C-containing algae which includes introducing a recombinant molecule comprising a nucleic acid molecule encoding a dominant selectable marker operatively linked to an algal regulatory control sequence into a chlorophyll C-containing alga in such a manner that the marker is produced by the alga. In a preferred embodiment the algal regulatory control sequence is derived from a diatom and preferably Cyclotella cryptica. Also disclosed is a chimeric molecule having one or more regulatory control sequences derived from one or more chlorophyll C-containing algae operatively linked to a nucleic acid molecule encoding a selectable marker, an RNA molecule and/or a protein, wherein the nucleic acid molecule does not normally occur with one or more of the regulatory control sequences. Further specifically disclosed are molecules pACCNPT10, pACCNPT4.8 and pACCNPT5.1. The methods and materials of the present invention provide the ability to accomplish stable genetic transformation of chlorophyll C-containing algae.

Dunahay, Terri Goodman (2710 Arbor Glen Pl., Boulder, CO 80304); Roessler, Paul G. (15905 Ellsworth Pl., Golden, CO 80401); Jarvis, Eric E. (3720 Smuggler Pl., Boulder, CO 80303)

1997-01-01

241

Ocean acidification weakens the structural integrity of coralline algae.  

PubMed

The uptake of anthropogenic emission of carbon dioxide is resulting in a lowering of the carbonate saturation state and a drop in ocean pH. Understanding how marine calcifying organisms such as coralline algae may acclimatize to ocean acidification is important to understand their survival over the coming century. We present the first long-term perturbation experiment on the cold-water coralline algae, which are important marine calcifiers in the benthic ecosystems particularly at the higher latitudes. Lithothamnion glaciale, after three months incubation, continued to calcify even in undersaturated conditions with a significant trend towards lower growth rates with increasing pCO2 . However, the major changes in the ultra-structure occur by 589?atm (i.e. in saturated waters). Finite element models of the algae grown at these heightened levels show an increase in the total strain energy of nearly an order of magnitude and an uneven distribution of the stress inside the skeleton when subjected to similar loads as algae grown at ambient levels. This weakening of the structure is likely to reduce the ability of the alga to resist boring by predators and wave energy with severe consequences to the benthic community structure in the immediate future (50years). PMID:24501058

Ragazzola, Federica; Foster, Laura C; Form, Armin; Anderson, Philip S L; Hansteen, Thor H; Fietzke, Jan

2012-09-01

242

AlgaePath: comprehensive analysis of metabolic pathways using transcript abundance data from next-generation sequencing in green algae  

PubMed Central

Background Algae are important non-vascular plants that have many research applications, including high species diversity, biofuel sources, and adsorption of heavy metals and, following processing, are used as ingredients in health supplements. The increasing availability of next-generation sequencing (NGS) data for algae genomes and transcriptomes has made the development of an integrated resource for retrieving gene expression data and metabolic pathway essential for functional analysis and systems biology. In a currently available resource, gene expression profiles and biological pathways are displayed separately, making it impossible to easily search current databases to identify the cellular response mechanisms. Therefore, in this work the novel AlgaePath database was developed to retrieve transcript abundance profiles efficiently under various conditions in numerous metabolic pathways. Description AlgaePath is a web-based database that integrates gene information, biological pathways, and NGS datasets for the green algae Chlamydomonas reinhardtii and Neodesmus sp. UTEX 22194. Users can search this database to identify transcript abundance profiles and pathway information using five query pages (Gene Search, Pathway Search, Differentially Expressed Genes (DEGs) Search, Gene Group Analysis, and Co-expression Analysis). The transcript abundance data of 45 and four samples from C. reinhardtii and Neodesmus sp. UTEX 22194, respectively, can be obtained directly on pathway maps. Genes that are differentially expressed between two conditions can be identified using Folds Search. The Gene Group Analysis page includes a pathway enrichment analysis, and can be used to easily compare the transcript abundance profiles of functionally related genes on a map. Finally, the Co-expression Analysis page can be used to search for co-expressed transcripts of a target gene. The results of the searches will provide a valuable reference for designing further experiments and for elucidating critical mechanisms from high-throughput data. Conclusions AlgaePath is an effective interface that can be used to clarify the transcript response mechanisms in different metabolic pathways under various conditions. Importantly, AlgaePath can be mined to identify critical mechanisms based on high-throughput sequencing. To our knowledge, AlgaePath is the most comprehensive resource for integrating numerous databases and analysis tools in algae. The system can be accessed freely online at http://algaepath.itps.ncku.edu.tw.

2014-01-01

243

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

PubMed

An algal-bacterial culture, composed of wastewater-born algae and activated sludge, was cultivated to treat domestic wastewater and accumulate biomass simultaneously. The influence of algae and sludge inoculation ratios on the treatment efficiency and the settleability of the accumulated biomass were investigated. There was no significant effect of the inoculation ratios on the chemical oxygen demand removal. Comparatively, the nutrients removal and related mechanism were varied with different inoculation ratios. The highest nitrogen and phosphorus removal efficiencies were observed with 5:1 (algae/sludge) culture (91.07.0% and 93.52.5%, respectively) within 10 days, which was 5-40% higher and 2-4 days faster than those with other inoculation ratios. The biomass settleability was improved with the assistance of sludge, and the 1:5 (algae/sludge) culture showed the best settleability. Furthermore, 16S rDNA gene analysis showed that the bacterial communities were varying with different algae and sludge inoculation ratios and some specific bacteria were enriched during operation. PMID:22189078

Su, Yanyan; Mennerich, Artur; Urban, Brigitte

2012-02-01

244

First case of human spondylodiscitis due to Shewanella algae.  

PubMed

We present the first case of human spondylodiscitis due to Shewanella algae. Our patient did not have any predisposing factors. The portal of entry was probably a cutaneous lesion on the leg, exposed to seawater. Bacteria were isolated in pure culture from a needle biopsy specimen of the vertebral disk. Automated identification systems identified the organism as Shewanella putrefaciens. However, molecular biology identified it as S. algae. Treatment with ceftriaxone and amikacin, then ciprofloxacin successfully addressed the infection. We also review four published cases of human osteoarticular infections caused by Shewanella spp: two cases of arthritis and two cases of osteomyelitis. Two patients had predisposing factors, and contact with water was found in two cases. The clinical, radiological and biological characteristics of S. algae spondylodiscitis are indistinguishable from those of spondylodiscitis of other causes. A cutaneous lesion with exposure to water is a potential portal of entry. Molecular typing is necessary to obtain a precise bacteriological identification. PMID:20171131

Gressier, M幨anie; Mbayo, Didier; Deramond, Herv; Grados, Franck; Eb, Fran蔞is; Canarelli, Brigitte

2010-09-01

245

Enhanced lipid extraction from algae using free nitrous acid pretreatment.  

PubMed

Lipid extraction has been identified as a major bottleneck for large-scale algal biodiesel production. In this work free nitrous acid (FNA) is presented as an effective and low cost pretreatment to enhance lipid recovery from algae. Two batch tests, with a range of FNA additions, were conducted to disrupt algal cells prior to lipid extraction by organic solvents. Total accessible lipid content was quantified by the Bligh and Dyer method, and was found to increase with pretreatment time (up to 48 h) and FNA concentration (up to 2.19 mg HNO2-N/L). Hexane extraction was used to study industrially accessible lipids. The mass transfer coefficient (k) for lipid extraction using hexane from algae treated with 2.19 mg HNO2-N/L FNA was found to be dramatically higher than for extraction from untreated algae. Consistent with extraction results, cell disruption analysis indicated the disruption of the cell membrane barrier. PMID:24632439

Bai, Xue; Naghdi, Forough Ghasemi; Ye, Liu; Lant, Paul; Pratt, Steven

2014-05-01

246

Benefits of using algae as natural sources of functional ingredients.  

PubMed

Algae have been suggested as a potential source of bioactive compounds to be used in the food and pharmaceutical industries. With the strong development of functional foods as a method to improve or maintain health, the exploration of new compounds with real health effects is now an intense field of research. The potential use of algae as source of functional food ingredients, such as lipids, proteins, polysaccharides, phenolics, carotenoids, etc., is presented, together with the different possibilities of improving valuable metabolites production either using the tools and the knowledge provided by marine biotechnology or improving the different factors involved in the production on a large scale of such metabolites. The bio-refinery concept is also presented as a way to improve the efficient use of algae biomass while favouring process sustainability. PMID:23339029

Iba鎑z, Elena; Cifuentes, Alejandro

2013-03-15

247

Designer proton-channel transgenic algae for photobiological hydrogen production  

DOEpatents

A designer proton-channel transgenic alga for photobiological hydrogen production that is specifically designed for production of molecular hydrogen (H.sub.2) through photosynthetic water splitting. The designer transgenic alga includes proton-conductive channels that are expressed to produce such uncoupler proteins in an amount sufficient to increase the algal H.sub.2 productivity. In one embodiment the designer proton-channel transgene is a nucleic acid construct (300) including a PCR forward primer (302), an externally inducible promoter (304), a transit targeting sequence (306), a designer proton-channel encoding sequence (308), a transcription and translation terminator (310), and a PCR reverse primer (312). In various embodiments, the designer proton-channel transgenic algae are used with a gas-separation system (500) and a gas-products-separation and utilization system (600) for photobiological H.sub.2 production.

Lee, James Weifu (Knoxville, TN)

2011-04-26

248

Cycloartane triterpenes from marine green alga Cladophora fascicularis  

NASA Astrophysics Data System (ADS)

Six cycloartanes were isolated from ethanol extract of marine green alga Cladophora fascicularis by column chromatography. Procedure of isolation and description of these compounds are given in this paper. The structures were elucidated as (1). 24-hydroperoxycycloart-25- en-3?-ol; (2). cycloart-25-en-3? 24-diol; (3). 25-hydroperoxycycloart-23-en-3?-ol; (4). cycloart-23-en-3?, 25-diol; (5). cycloart-23, 25-dien-3?-ol; and (6). cycloart-24-en-3?-ol by spectroscopic (MS, ID and 2D NMR) data analysis. Cycloartane derivatives are widely distributed in terrestrial plants, but only few were obtained in the alga. All these compounds that have been isolated from terrestrial plants, were found in the marine alga for the first time.

Huang, Xinping; Zhu, Xiaobin; Deng, Liping; Deng, Zhiwei; Lin, Wenhan

2006-12-01

249

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

2011-01-01

250

Value of crops: Quantity, quality and cost price. [algae as a nutritional supplement  

NASA Technical Reports Server (NTRS)

Possibilities of using algae as a nutritional supplement are examined. The nutritional value and protein content of spirulines of blue algae are discussed. A cost analysis of growing them artificially is presented.

Meyer, C.

1979-01-01

251

Smallest algae thrive as the Arctic Ocean freshens.  

PubMed

As climate changes and the upper Arctic Ocean receives more heat and fresh water, it becomes more difficult for mixing processes to deliver nutrients from depth to the surface for phytoplankton growth. Competitive advantage will presumably accrue to small cells because they are more effective in acquiring nutrients and less susceptible to gravitational settling than large cells. Since 2004, we have discerned an increase in the smallest algae and bacteria along with a concomitant decrease in somewhat larger algae. If this trend toward a community of smaller cells is sustained, it may lead to reduced biological production at higher trophic levels. PMID:19900890

Li, William K W; McLaughlin, Fiona A; Lovejoy, Connie; Carmack, Eddy C

2009-10-23

252

Heavy metals in marine algae of the Kuwait coast  

SciTech Connect

Marine algae are considered as important primary producers in the coastal region. Several marine algal species are being considered as raw material for various economically important products and this has resulted in their increasing demand. Marine algal species also have been suggested to be the indicators of pollution. Keeping in view the importance of marine algal species for direct or indirect human and cattle consumption, it is necessary to monitor the bioaccumulation of certain elements in these species. This study was aimed at establishing the concentration levels of trace metals in marine algae of the Kuwait coast. 26 refs., 1 fig., 3 tabs.

Buo-Olayan, A.H.; Subrahmanyam, M.N.V. [Kuwait Univ., Safat (Kuwait)] [Kuwait Univ., Safat (Kuwait)

1996-12-31

253

Homogeneity of Danish Environmental and Clinical Isolates of Shewanella algae  

PubMed Central

Danish isolates of Shewanella algae constituted by whole-cell protein profiling a very homogeneous group, and no clear distinction was seen between strains from the marine environment and strains of clinical origin. Although variation between all strains was observed by ribotyping and random amplified polymorphic DNA analysis, no clonal relationship between infective strains was found. From several patients, clonally identical strains of S. algae were reisolated up to 8 months after the primary isolation, indicating that the same strain may be able to maintain the infection.

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

2000-01-01

254

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

255

Treatment failure due to emergence of resistance to carbapenem during therapy for Shewanella algae bacteremia.  

PubMed

We describe a case of bacteremia due to imipenem-susceptible Shewanella algae. Despite treatment with imipenem, the patient developed a spinal epidural abscess, from which imipenem-resistant S. algae was isolated. The development of resistance should be monitored when S. algae infection is treated with imipenem, even though the strain is initially susceptible to imipenem. PMID:16517923

Kim, Dong-Min; Kang, Cheol-In; Lee, Chang Seop; Kim, Hong-Bin; Kim, Eui-Chong; Kim, Nam Joong; Oh, Myoung-Don; Choe, Kang-Won

2006-03-01

256

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

257

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

EPA Science Inventory

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

258

Effectiveness of algae in the treatment of a wood-based pulp and paper industry wastewater  

Microsoft Academic Search

In this study, the ability of algae to treat a wood-based pulp and paper industry wastewater was investigated. Tests were performed in batch reactors seeded with a mixed culture of algae. Under different lighting and initial wastewater strength conditions, changes in COD, AOX and color contents of reactors were followed with time. Algae were found to remove up to 58%

Esra Tarlan; Filiz B. Dilek; Ulku Yetis

2002-01-01

259

???????????????????????????????????????????????????????????????? Reduction of Acidity in Drainage Water from Acid Sulfate Soil using Algae  

Microsoft Academic Search

Algae generally prefer a humid and near neutral to alkaline pH condition for growing due to the availability of inorganic carbon in the form of bicarbonate and carbonate. As algae grow and extract carbon dioxide from water (bicarbonate and carbonate), the pH of water tends to increase. This study intends to isolate acid tolerant algae to use for reduction of

Panida Preepremmot; Kannika Sajjaphan

260

Resistance and susceptibility of algae to decomposition by natural microbial communities  

Microsoft Academic Search

The susceptibility to microbial decomposition of species of 14 algae was assessed in pond water and with inocula from several environments. Some of the algae were destroyed in short periods, but others withstood microbial digestion for more than 4 weeks. The production of toxins did not account for the resistance of those algae not readily destroyed microbiologically. The suitability of

Douglas GunnisonL; MARTIN ALEXANDER

1975-01-01

261

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 ...

262

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

263

Treatment Failure Due to Emergence of Resistance to Carbapenem during Therapy for Shewanella algae Bacteremia  

PubMed Central

We describe a case of bacteremia due to imipenem-susceptible Shewanella algae. Despite treatment with imipenem, the patient developed a spinal epidural abscess, from which imipenem-resistant S. algae was isolated. The development of resistance should be monitored when S. algae infection is treated with imipenem, even though the strain is initially susceptible to imipenem.

Kim, Dong-Min; Kang, Cheol-In; Lee, Chang Seop; Kim, Hong-Bin; Kim, Eui-Chong; Kim, Nam Joong; Oh, Myoung-don; Choe, Kang-Won

2006-01-01

264

Biological Activities and Potential Health Benefits of Fucoxanthin Derived from Marine Brown Algae  

Microsoft Academic Search

The importance of marine algae as sources of functional ingredients has been well recognized due to their valuable health beneficial effects. Therefore, isolation and investigation of novel bioactive ingredients with biological activities from marine algae have attracted great attention. Among functional ingredients identified from marine algae, fucoxanthin has received particular interest. Fucoxanthin has been attributed with extraordinary potential for protecting

Se-Kwon Kim; Ratih Pangestuti

2011-01-01

265

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

266

Homogeneity of Danish Environmental and Clinical Isolates of Shewanella algae  

Microsoft Academic Search

Danish isolates of Shewanella algae constituted by whole-cell protein profiling a very homogeneous group, and no clear distinction was seen between strains from the marine environment and strains of clinical origin. Although variation between all strains was observed by ribotyping and random amplified polymorphic DNA analysis, no clonal relationship between infective strains was found. From several patients, clonally identical strains

BIRTE FONNESBECH VOGEL; HANNE MARIE HOLT; PETER GERNER-SMIDT; ANEMONE BUNDVAD; P. Sogaard; LONE GRAM

2000-01-01

267

Late ventriculoperitoneal shunt infection caused by Shewanella algae.  

PubMed

We present a case of ventriculitis and peritonitis in a child with ventriculoperitoneal shunt, which occurred 5 years after the surgery. The infection developed after contact with seawater and began as otitis. For the first time, Shewanella algae, a marine microorganism, was identified as the cause of ventriculoperitoneal shunt infection. PMID:19952978

Sardelic, Sanda; Karanovic, Jakica; Rubic, Zana; Polic, Branka; Ledenko, Vlatko; Markic, Josko; Mestrovic, Julije

2010-05-01

268

On site photosynthetic performance of Atlantic green algae  

Microsoft Academic Search

Photosynthetic performance was measured on site in four common Atlantic green algae, Asparagopsis taxiforme, Valonia utricularia, Caulerpa racemosa and Codium taylori, in Gran Canaria, Canary Islands. The photosynthetic quantum yield was determined with a portable PAM instrument and with a diving PAM in the water column. Solar radiation was measured continuously above and in the water column by means of

Donat-P H輐er; Markus Porst; Michael Lebert

2000-01-01

269

Phosphomannomutase and phosphoglucomutase in the red alga Galdieria sulphuraria  

Microsoft Academic Search

The enzymes phosphoglucomutase (PGM) and phosphomannomutase (PMM) from the red alga Galdieria sulphuraria were separated from each other on hydroxylapatite. PGM is specific for glucose phosphates as substrates. PMM on the other hand is bifunctional for glucose phosphates and mannose phosphates. Both substrates are competitive. These findings are similar to characteristics of PGM and PMM from other organisms, although PGM

Christine Oesterhelt; Claus Schnarrenberger; Wolfgang Gross

1996-01-01

270

Medicinal Effects of Phlorotannins from Marine Brown Algae  

Microsoft Academic Search

Brown seaweeds are popular and abundant food in East Asia and also well known for their medicinal effects due to presence of active phenolic constituents. Phlorotannins, the major phenolic group of brown algae, have extensively investigated for their vast array of bioactivities such as antioxidant, anti-inflammatory, anticancer, and antidiabetic. They possess promising activity in both in vitro and in vivo

Se-Kwon Kim; S. W. A. Himaya

2011-01-01

271

Adhesion strength of settled spores of the green alga Enteromorpha  

Microsoft Academic Search

Strengths of attachment of spores of the green fouling alga Enteromorpha to glass have been measured using a modified water jet apparatus. Surface pressures of ?250 kPa were required to quantitatively remove attached spores after 4 h contact with a surface. The development of adhesive and cohesive strength is highly time-dependent; after 8 h in contact with a surface spores

J A Finlay; Maureen E Callow; M P Schultz; G W Swain; J A Callow

2002-01-01

272

Thermochemical Conversion of Mosses and Algae to Gaseous Products  

Microsoft Academic Search

The effect of temperature on the yield of hydrogen from two mosses (Polytrichum commune and Thuidium tamarascinum) and two algae (Cladophora fracta and Chlorella protothecoid) by pyrolysis and steam gasification were investigated in this study. In each run, the main components of the gas phase were CO2, CO, H2, and CH4. The yields of hydrogen by pyrolysis and steam gasification

A. Demirbas

2009-01-01

273

Expression and assembly of a fully active antibody in algae  

NASA Astrophysics Data System (ADS)

Although combinatorial antibody libraries have solved the problem of access to large immunological repertoires, efficient production of these complex molecules remains a problem. Here we demonstrate the efficient expression of a unique large single-chain (lsc) antibody in the chloroplast of the unicellular, green alga, Chlamydomonas reinhardtii. We achieved high levels of protein accumulation by synthesizing the lsc gene in chloroplast codon bias and by driving expression of the chimeric gene using either of two C. reinhardtii chloroplast promoters and 5' and 3' RNA elements. This lsc antibody, directed against glycoprotein D of the herpes simplex virus, is produced in a soluble form by the alga and assembles into higher order complexes in vivo. Aside from dimerization by disulfide bond formation, the antibody undergoes no detectable posttranslational modification. We further demonstrate that accumulation of the antibody can be modulated by the specific growth regime used to culture the alga, and by the choice of 5' and 3' elements used to drive expression of the antibody gene. These results demonstrate the utility of alga as an expression platform for recombinant proteins, and describe a new type of single chain antibody containing the entire heavy chain protein, including the Fc domain.

Mayfield, Stephen P.; Franklin, Scott E.; Lerner, Richard A.

2003-01-01

274

The development of artificial media for marine algae  

Microsoft Academic Search

The culturing of marine algae has proceeded slowly since MIQV~L (1890 93) succeeded in growing a few diatoms in the laboratory. Until recently most media were composed of sea water or sea water-like artificial solutions which are prone to precipitate because of the presence of several salts in concentration near saturation. In order to avoid precipitates such media must be

L. Provasoli; J. J. A. McLaughlin; M. R. Droop

1957-01-01

275

Hawaiian Marine Algae from Seaward of the Algal Ridge.  

National Technical Information Service (NTIS)

From fifty-four dredge hauls between the 10- and 165-m depths in Hawaii twenty-one benthic algal species, mostly minute red algae, have been added to the Hawaiian flora. While 101 species are reported, no distinctive deep water flora, zonation or dominanc...

M. S. Doty W. J. Gilbert I. A. Abbott

1974-01-01

276

Adaptive control of algae detachment in regulated canal networks  

Microsoft Academic Search

Open-channels networks used for water distribution are subject to algal developments that can induce major dis- turbances such as clogging issues on hydraulic devices (pipes, weirs, filters,...). We already studied the use of flushes to manage these algae developments. The flush is carried out by increasing the hydraulic shear conditions using the hydraulic structures of the canal network. In response

Xavier Litrico; Gilles Belaud; Ophelie Fovet

2011-01-01

277

Ocean Planet: There Are Algae in Your House!  

NSDL National Science Digital Library

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

278

ASPECTS OF PHOSPHATE UTILIZATION BY BLUE-GREEN ALGAE  

EPA Science Inventory

The effects of various external phosphate concentrations on physiological and cytological aspects of Plectonema boryanum have been studied. P. boryanum was found to tolerate a wide range of phosphate concentrations, from 1 to 1000 mg of phosphate per liter. Growth of the alga in ...

279

HYDRA VIRIDIS: TRANSFER OF METABOLITES BETWEEN HYDRA AND SYMBIOTIC ALGAE  

Microsoft Academic Search

?Back transferof metabolites from food to endosymbiotic algae in the digestive cells of Hydra viridis was demonstrated. Brine shrimp nauplii labeled with tritiated precursors of protein and nucleic acids (DNA and RNA) were fed to light and dark grown hydras. The fate of the label after a single feeding with radioactive material in hydra and algal fractions was followed by

GLYNE THORINGTON; LYNN MARGULIS

280

Phytochelatin production in marine algae. 1. An interspecies comparison  

Microsoft Academic Search

Phytochelatins are metal-binding peptides produced enzymatically by higher plants, fungi, and algae in response to many metals, particularly Cd. We have studied phytochelatin production in several marine phytoplankton exposed to a range of free Cd ion concentrations. As a result of increased analytical resolution, we have found that all the species contain phytochelatin, even when there is no added Cd,

BETH A. AHNER; SHING KONG; FRANシIS M. M. MOREL

1995-01-01

281

Gas Vacuole Development in a Blue-Green Alga  

Microsoft Academic Search

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

J. Robert Waaland; Daniel Branton

1969-01-01

282

Toxins of a Blue-Green Alga: Similarity to Saxitoxin  

Microsoft Academic Search

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.

Eugene Jackim; John Gentile

1968-01-01

283

INFLUENCE OF ALGAE ON PHOTOLYSIS RATES OF CHEMICALS IN WATER  

EPA Science Inventory

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

284

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

285

Spectral shifting by dyes to enhance algae growth  

SciTech Connect

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

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

1984-11-01

286

Mucilage secretion and the movements of blue-green algae  

Microsoft Academic Search

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

A. E. Walsby

1968-01-01

287

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

288

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

289

Basis for the Resistance of Several Algae to Microbial Decomposition  

PubMed Central

The basis for the resistance of certain algae to microbial decomposition in natural waters was investigated using Pediastrum duplex, Staurastrum sp., and Fischerella muscicola as test organisms. Enzyme preparations previously found to convert susceptible algae into spheroplasts had no such effect on the resistant species, although glucose and galacturonic acid were released from P. duplex walls. Little protein or lipid but considerable carbohydrate was found in the walls of the refractory organisms, but resistance was not correlated with the presence of a unique sugar monomer. A substance present in Staurastrum sp. walls was characterized as lignin or lignin-like on the basis of its extraction characteristics, infrared spectrum, pyrolysis pattern, and content of an aromatic building block. Sporopollenin was found in P. duplex, and cellulose in Staurastrum sp. Cell walls of the algae were fractionated, and the fractions least susceptible to microbial degradation were the sporopollenin of P. duplex, the polyaromatic component of Staurastrum sp., and two F. muscicola fractions containing several sugar monomers. The sporopollenin content of P. duplex, the content of lignin or a related constituent of Staurastrum sp., and the resistance of the algae to microbial attack increased with age. It is suggested that resistance results from the presence of sporopollenin in P. duplex, a lignin-like material in Staurastrum sp., and possibly heteropolysaccharides in F. muscicola.

Gunnison, Douglas; Alexander, Martin

1975-01-01

290

BIOCONCENTRATION OF A HEXACHLOROBIPHENYL IN GREAT LAKES PLANKTONIC ALGAE  

EPA Science Inventory

The bioconcentration of 2,4,5,2',4',5'-hexachlorobiphenyl (HCB) was examined in the Great Lakes algae Fragilaria crotonensis, Ankistrodesmus falcatus, and Microcystis sp. The bioconcentration factors varied from species to species, whether they were expressed in terms of cell num...

291

Microbial Colonization and Competition on the Marine Alga Ulva australis  

Microsoft Academic Search

Pseudalteromonas tunicata and Roseobacter gallaeciensis are biofilm-forming marine bacteria that are often found in association with the surface of the green alga Ulva australis. They are thought to benefit the plant host by producing inhibitory compounds that are active against common fouling organisms. We investigated factors that influence the ability of P. tunicata and R. gallaeciensis to attach to and

Dhana Rao; Jeremy S. Webb; Staffan Kjelleberg

2006-01-01

292

Phylogeny and Molecular Evolution of the Green Algae  

Microsoft Academic Search

The green lineage (Viridiplantae) comprises the green algae and their descendants the land plants, and is one of the major groups of oxygenic photosynthetic eukaryotes. Current hypotheses posit the early divergence of two discrete clades from an ancestral green flagellate. One clade, the Chlorophyta, comprises the early diverging prasinophytes, which gave rise to the core chlorophytes. The other clade, the

Frederik Leliaert; David R. Smith; Herv Moreau; Matthew D. Herron; Heroen Verbruggen; Charles F. Delwiche; Olivier De Clerck

2012-01-01

293

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

294

Mg-lattice associations in red coralline algae  

Microsoft Academic Search

Recent investigations have shown red coralline algae to record ambient temperature in their calcite skeletons. Temperature recorded by variation in Mg concentrations within algal growth bands has sub-annual resolution and high accuracy. The conversion of Mg concentration to temperature is based on the assumption of Ca replacement by Mg within the algal calcite skeleton at higher temperatures. While Mg-temperature relationships

N. A. Kamenos; M. Cusack; T. Huthwelker; P. Lagarde; R. E. Scheibling

2009-01-01

295

Coralline algae are global palaeothermometers with bi-weekly resolution  

Microsoft Academic Search

High resolution palaeoclimate data are required for the Holocene to resolve differences recorded by current proxies. The pole to pole distribution of rhodoliths (coralline algae) with their annual and sub-annual calcite bands make these attractive candidates for such a role. These bands contain climate information in the form of elemental traces. In situ temperature (IST) was recorded at two rhodolith

N. A. Kamenos; M. Cusack; P. G. Moore

2008-01-01

296

Fatty acid amides from freshwater green alga Rhizoclonium hieroglyphicum.  

PubMed

Freshwater green algae Rhizoclonium hieroglyphicum growing in the Ural Mountains were examined for their fatty acid amides using capillary gas chromatography-mass spectrometry (GC-MS). Eight fatty acid amides were identified by GC-MS. (Z)-9-octadecenamide was found to be the major component (2.26%). PMID:11014298

Dembitsky, V M; Shkrob, I; Rozentsvet, O A

2000-08-01

297

Degradation of Petroleum by an Alga, 'Prototheca zopfii'.  

National Technical Information Service (NTIS)

Prototheca zopfii is an achlorophyllous alga which degrades oil. It has been found to degrade 10 and 40% of a motor oil and crude oil, respectively, when tested under appropriate conditions. Degradation of the crude oil observed in this study compares wel...

J. D. Walker R. R. Colwell L. Petrakis

1975-01-01

298

Toxicity of paraquat to a green alga scenedesmus acutus  

Microsoft Academic Search

An algal toxicity test was conducted to evaluate the toxic effects on a freshwater alga of increasing concentrations of the herbicide paraquat upon growth, chlorophyll and protein content. Paraquat, a widely used herbicide, was found highly toxic to Scenedesmus acutus. Growth pattern, as well as growth rates and generation times exhibited by the cultures exposed up to 0.05 mg Pq\\/L,

Mar燰 Elena S墈nz; Juan Accorinti; Mar燰 del Carmen Tortorelli

1993-01-01

299

Biosorption of reactive dyes on the green alga Chlorella vulgaris  

Microsoft Academic Search

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

Zmriye Aksu; Sevilay Tezer

2005-01-01

300

Survey of Hydrogenase Activity in Algae: Final Report  

SciTech Connect

The capacity for hydrogen gas production was examined in nearly 100 strains of Eukaryotic algae. Each strain was assessed for rate of H2 production in darkness, at compensating light intensity and at saturating Tight intensity. Maximum H2 yield on illumination and sensitivity to molecular oxygen were also measured.

Brand, J. J.

1982-04-01

301

Photosynthetic Hydrogen and Oxygen Production by Green Algae.  

National Technical Information Service (NTIS)

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, mo...

E. Greenbaum J. W. Lee

1999-01-01

302

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

303

Switchable photosystem-II designer algae for photobiological hydrogen production  

DOEpatents

A switchable photosystem-II designer algae for photobiological hydrogen production. The designer transgenic algae includes at least two transgenes for enhanced photobiological H.sub.2 production wherein a first transgene serves as a genetic switch that can controls photosystem II (PSII) oxygen evolution and a second transgene encodes for creation of free proton channels in the algal photosynthetic membrane. In one embodiment, the algae includes a DNA construct having polymerase chain reaction forward primer (302), a inducible promoter (304), a PSII-iRNA sequence (306), a terminator (308), and a PCR reverse primer (310). In other embodiments, the PSII-iRNA sequence (306) is replaced with a CF.sub.1-iRNA sequence (312), a streptomycin-production gene (314), a targeting sequence (316) followed by a proton-channel producing gene (318), or a PSII-producing gene (320). In one embodiment, a photo-bioreactor and gas-product separation and utilization system produce photobiological H.sub.2 from the switchable PSII designer alga.

Lee, James Weifu (Knoxville, TN)

2010-01-05

304

Life Strategies of Filamentous Algae in the Northern Baltic Proper  

Microsoft Academic Search

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

Mikko Kiirikki; Annamaija Lehvo

1997-01-01

305

Research on the life cycles of harmful algae: A commentary  

Microsoft Academic Search

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

Karen A. Steidinger

2010-01-01

306

LAKE PEND OREILLE, IDAHO - ATTACHED BENTHIC ALGAE (PERIPHYTON), 1986  

EPA Science Inventory

Attached algae in the littoral zone of Pend Oreille Lake, a large deep meso-oligotrophic lake in northern Idaho (17010214) was studied for comparison to estimates of pelagic productivity. The study monitored periphyton growth rates during July and August 1986 on both artificial ...

307

The Protein Quality of Waste-grown Green Algae I. QUALITY OF PROTEIN IN MIXTURES OF ALGAE, NONFAT POWDERED MILK, AND CEREALS1  

Microsoft Academic Search

The protein efficiency ratio (PER) was determined, as a measure of protein quality, on thick gruels and on baked products containing waste-grown green algae, a mixture of Scenedesmus quadricauda and Chlorella, spp., at a ratio of 10:1. Algae-cereal-nonfat dry milk mixtures (the algae and cereals boiled for 30 minutes to make a thick gruel) and milk added to the cooked

BESSIE B. COOK; ESTHER W. LAU; ANDBETTY M. BAILEY

308

FERMENTATIVE AND PHOTOCHEMICAL PRODUCTION OF HYDROGEN IN ALGAE.  

PubMed

1.. After 2 hours of fermentation in nitrogen the metabolism of those algae which were found capable of photoreduction with hydrogen changes in such a way that molecular hydrogen is released from the cell in addition to carbon dioxide. 2. The amount of hydrogen formed anaerobically in the dark depends on the amount of some unknown reserve substance in the cell. More hydrogen is formed in presence of added glucose, but no proportionality has been found between the amount of substrate added and that of hydrogen formed. This is probably due to the fact that two types of fermentation reactions exist, with little or no connection between them. Whereas mainly unknown organic acids are formed during the autofermentation, the addition of glucose causes a considerable increase in the production of lactic acid. 3. Algae which have been fermenting for several hours in the dark produce upon illumination free hydrogen at several times the rate observed in the dark, provided carbon dioxide is absent. 4. Certain concentrations of dinitrophenol strongly inhibit the evolution of hydrogen in the dark. Fermentation then continues mainly as a reaction leading to lactic acid. In such poisoned algae the photochemical liberation of hydrogen still continues. 5. If the algae are poisoned with dinitrophenol the presence of carbon dioxide will not interfere with the photochemical evolution of hydrogen. 6. The amount of hydrogen released in this new photochemical reaction depends on the presence of an unknown hydrogen donor in the cell; it can be increased by the addition of glucose but not in proportion to the amount added. 7. The results obtained allow for a more correct explanation of the anaerobic induction period previously described for Scenedesmus and similar algae. The possibility of a photochemical evolution of hydrogen had not been taken into account in the earlier experiments. 8. The origin of the hydrogen released under the influence of light is discussed. PMID:19873339

Gaffron, H; Rubin, J

1942-11-20

309

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

310

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

311

Isolation of an allelopathic substance from the crustose coralline algae, Lithophyllum spp., and its effect on the brown alga, Laminaria religiosa Miyabe (Phaeophyta)  

Microsoft Academic Search

An allelopathic substance that destroys zoospores of the brown alga, Laminaria religiosa Miyabe, was isolated by several separation techniques from the ethanol extract of the crustose coralline alga, Lithophyllum spp. A bioassay was used to test the effect of isolated fractions against the dinoflagellate, Heterosigma akashiwo Hada, and zoospores of L. religiosa. Further purification of the allelopathic substance in ether

Yoshihiro Suzuki; Tadashi Takabayashi; Tomohiro Kawaguchi; Katsuhiko Matsunaga

1998-01-01

312

Application of novel extraction technologies for bioactives from marine algae.  

PubMed

Marine algae are a rich source of bioactive compounds. This paper outlines the main bioactive compounds in marine algae and recent advances in novel technologies for extracting them. Novel extraction technologies reviewed include enzyme-assisted extraction, microwave-assisted extraction, ultrasound-assisted extraction, supercritical fluid extraction, and pressurized liquid extraction. These technologies are reviewed with respect to principles, benefits, and potential applications for marine algal bioactives. Advantages of novel technologies include higher yield, reduced treatment time, and lower cost compared to traditional solvent extraction techniques. Moreover, different combinations of novel techniques used for extraction and technologies suitable for thermolabile compounds are identified. The limitations of and challenges to employing these novel extraction technologies in industry are also highlighted. PMID:23634989

Kadam, Shekhar U; Tiwari, Brijesh K; O'Donnell, Colm P

2013-05-22

313

Sodium, potassium-atpases in algae and oomycetes.  

PubMed

We have investigated the presence of K(+)-transporting ATPases that belong to the phylogenetic group of animal Na(+),K(+)-ATPases in the Pythium aphanidermatum Stramenopile oomycete, the Porphyra yezoensis red alga, and the Udotea petiolata green alga, by molecular cloning and expression in heterologous systems. PCR amplification and search in EST databases allowed one gene to be identified in each species that could encode ATPases of this type. Phylogenetic analysis of the sequences of these ATPases revealed that they cluster with ATPases of animal origin, and that the algal ATPases are closer to animal ATPases than the oomycete ATPase is. The P. yezoensis and P. aphanidermatum ATPases were functionally expressed in Saccharomyces cerevisiae and Escherichia coli alkali cation transport mutants. The aforementioned cloning and complementary searches in silicio for H(+)- and Na(+),K(+)-ATPases revealed a great diversity of strategies for plasma membrane energization in eukaryotic cells different from typical animal, plant, and fungal cells. PMID:16167182

Barrero-Gil, Javier; Garciadebl嫳, Blanca; Benito, Bego鎙

2005-08-01

314

Hydrocarbons in green and blue-green algae.  

PubMed

Liquid column chromatography and thin-layer chromatography were used to determine the total content of hydrocarbons and gas chromatography was used to evaluate composition of hydrocarbons in green algae (Chlorella kessleri, C. vulgaris, Chlorella sp., Scenedesmus acutus, S. acuminatus, S. obliquus) and the blue-green alga (Spirulina platensis) cultivated under autotrophic or heterotrophic conditions. In C. kessleri cultivated under heterotrophic conditions the content of hydrocarbons was found to be about 10(-2)% (per dry mass), whereas under autotrophic conditions it was about 10(-3)% (per dry mass). The highest content of hydrocarbons was detected in species of the genus Scenedesmus cultivated autotrophically (10(-1)%). Heptadecane and hexacosane were found as major alkanes, 1-heptadecene was detected among alkenes. PMID:6816708

Rezanka, T; Zahradn璭, J; Podojil, M

1982-01-01

315

Biosorption of lead and nickel by biomass of marine algae  

SciTech Connect

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

Holan, Z.R.; Volesky, B. (McGill Univ., Montreal, Quebec (Canada). Dept. of Chemical Engineering)

1994-05-01

316

Biodegradable thermoplastic composites based on polyvinyl alcohol and algae.  

PubMed

Algae constitute a largely available, low value material from renewable resources of marine origin to be used for the production of eco-compatible composites. Fibers of the green alga Ulva armoricana from the French coast were positively evaluated for the production of composites with a hydrophilic, eco-compatible polymer, such as poly(vinyl alcohol) (PVA) as continuous matrix by casting of aqueous suspensions and compression molding. PVA, Ulva, and starch were also successfully processed by the melt in the presence of glycerol. Positive results were obtained for film-forming properties and mechanical characteristics also with limited amounts of PVA (40%) attesting for Ulva suitability to be introduced in composites (up to 30%). Degradation in soil of Ulva and an Ulva-based composites outlined a rapid mineralization of Ulva in the selected medium (over 80% in 100 days) while the composite samples underwent a mineralization rate affected by the different component propensity to degradation. PMID:18257530

Chiellini, Emo; Cinelli, Patrizia; Ilieva, Vassilka I; Martera, Martina

2008-03-01

317

Genetic structure of the subtidal red alga Delisea pulchra  

Microsoft Academic Search

We used random amplified polymorphic DNA (RAPDs) to examine small-scale spatial genetic structure in the red alga Delisea pulchra (Greville) Montagne at two locations near Sydney, Australia. We examined genetic structure among plants at four spatial scales\\u000a ranging from 2?km apart down to <50?cm apart between locations, among sites within locations, among quadrats within sites,\\u000a and among plants within quadrats.

J. T. Wright; G. C. Zuccarello; P. D. Steinberg

2000-01-01

318

Antifungal Bromophenols from Marine Red Alga Symphyocladia latiuscula.  

PubMed

Three new highly brominated polyphenols, 1-3, together with one known bromophenol, 4, were isolated from the EtOH extract of a marine red alga Symphyocladia latiuscula collected from the coast of Qingdao, P.?R. China. Their structures were identified by extensive spectroscopic experiments (NMR and MS) and comparison with literature data. Compounds 3 and 4 showed activities against the Candida albicans with the MIC values of 25 and 12.5??g/ml, respectively. PMID:24827691

Xu, Xiuli; Yin, Liyuan; Gao, Junhai; Gao, Lijie; Song, Fuhang

2014-05-01

319

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

320

A new survey of Brazilian marine algae for agglutinins  

Microsoft Academic Search

Aqueous protein extracts from 30 Brazilian marine algae were examined for haemagglutinating activity using native and enzyme-treated\\u000a rabbit, chicken, sheep and human erythrocytes. Most extracts agglutinated at least one of the blood cells used. Sheep and\\u000a rabbit erythrocytes were more suitable for detection of the agglutinating activity. The minimum protein concentration necessary\\u000a to produce positive agglutination was usually lower with

A. L. P. Freitas; D. I. A. Teixeira; F. H. F. Costa; W. R. L. Farias; A. S. C. Lobato; A. H. Sampaio; N. M. B. Benevides

1997-01-01

321

Surface gas-exchange processes of snow algae  

Microsoft Academic Search

The red-colored chlorophyte Chlamydomonas nivalis is commonly found in summer snowfields. We used a modified Li-Cor gas-exchange system to investigate surface gas-exchange characteristics of snow colonized by this alga, finding rates of CO2 uptake up to 0.3 mumol m2新1 in dense algal blooms. Experiments varying the irradiance resulted in light curves that resembled those of the leaves of higher plants.

William E. Williams; Holly L. Gorton; Thomas C. Vogelmann

2003-01-01

322

Algae sequester heavy metals via synthesis of phytochelatin complexes  

Microsoft Academic Search

A Cd-binding complex was isolated from Chlorella fusca and has been shown to be composed of phytochelating peptides, (?-Glu-Cys)n-Gly, n=25. Members of six of the ten classes of Phycophyta revealed phytochelatin synthesis after exposure to cadmium ions. Phytochelatin was also induced by ions of lead, zinc, silver, copper and mercury. These experiments uneqiovocally demonstrated that algae sequester heavy metals by

Walter Gekeler; Erwin Grill; Ernst-Ludwig Winnacker; Meinhart H. Zenk

1988-01-01

323

Blue-Green Algae: Fine Structure of the Gas Vacuoles  

Microsoft Academic Search

The gas vacuoles seen in several species of blue-green algae under the light microscope are shown by electron microscopy to correspond to packed arrays of cylindrical, electron-transparent vesicles. Single vesicles average 75 millimicrons in diameter, range from 0.2 micron to 1.0 micron in length, have conical ends, and are bounded by a single membrane 2 millimicrons wide. The reversible disappearance

C. C. Bowen; T. E. Jensen

1965-01-01

324

Mathematical simulation of photophobic responses in blue-green algae  

SciTech Connect

A computer model is described to simulate photophobic reversal of blue-green algae. The model is based on electrical potential changes within the cells, which are treated as separate compartments. The updating of potentials is accomplished through iterative calculation of recurrence equations, permitting easy programming for computer calculation. The influence of a number of conditions on photophobic reversal has been studied, and the predictions of the model have been verified by experiments with the living organisms.

Hader, D.P.; Burkart, U.

1982-01-01

325

Antioxidant role of astaxanthin in the green alga Haematococcus pluvialis  

Microsoft Academic Search

The green unicellular alga, Haematococcus pluvialis has two antioxidative mechanisms against environmental oxidative stress: antioxidative enzymes in vegetative cells and the\\u000a antioxidative ketocarotenoid, astaxanthin, in cyst cells. We added a reagent that generates superoxide anion radicals (O2\\u000a ?), methyl viologen, to mature and immature cysts of H. pluvialis. Tolerance to methyl viologen was higher in mature than in immature cysts.

M. Kobayashi; T. Kakizono; N. Nishio; S. Nagai; Y. Kurimura; Y. Tsuji

1997-01-01

326

Biosorption of cadmium by biomass of marine algae  

Microsoft Academic Search

Biomass of nonliving, dried brown marine algae Sargassum natans, Fucus vesiculosus, and Ascophyllum nodosum demonstrated high equilibrium uptake of cadmium from aqueous solutions. The metal uptake by these materials was quantitatively evaluated using sorption isotherms. Biomass of A. nodosum accumulated the highest amount of cadmium exceeding 100 mg Cd[sup 2+]\\/g (at the residual concentration of 100 mg Cd\\/L and pH

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

1993-01-01

327

Tyrosinase inhibitors isolated from the edible brown alga Ecklonia stolonifera  

Microsoft Academic Search

Extracts from seventeen seaweeds were determined for tyrosinase inhibitory activity using mushroom tyrosinase with L-tyrosine\\u000a as a substrate. Only one of them,Ecklonia stolonifera\\u000a Okamura (Laminariaceae) belonging to brown algae, showed high tyrosinase inhibitory activity. Bioassay-guided fractionation of the\\u000a active ethyl acetate (EtOAc) soluble fraction from the methanolic extract ofE. stolonifera, led us to the isolation of phloroglucinol derivatives [phloroglucinol (1),

Hye Sook Kang; Hyung Rak Kim; Dae Seok Byun; Byeng Wha Son; Taek Jeong Nam; Jae Sue Choi

2004-01-01

328

Modeling algae growth in an open-channel raceway  

Microsoft Academic Search

Cost-effective implementation of microalgae as a solar-to-chemical energy conversion platform requires extensive system optimization; computer modeling can bring this to bear. This work uses modified versions of the U.S. Environmental Protection Agency's (EPA's) Environmental Fluid Dynamics Code (EFDC) in conjunction with the U.S. Army Corp of Engineers water-quality code (CE-QUAL) to simulate hydrodynamics coupled to growth kinetics of algae (Phaeodactylum

Scott C. James; Scott Carlton

2010-01-01

329

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

330

Microbial fucoidan degradation by Luteolibacter algae H18 with deacetylation.  

PubMed

A bacterial strain that assimilates fucoidan from Cladosiphon okamuranus as sole carbon source was isolated as Luteolibacter algae H-18. It was found that it degraded fucoidan by intracellular enzymes, and that the degradation reactions were catalyzed by multiple enzymes. One enzyme, designated fraction B, was established to exhibit the deacetylation reaction of fucoidan. Other enzyme(s), designated fraction A, catalyzed the reaction(s) lowering the molecular weight of fucoidan. PMID:22451414

Ohshiro, Takashi; Harada, Naomi; Kobayashi, Yasuaki; Miki, Yasunari; Kawamoto, Hitoshi

2012-01-01

331

Colour and AOX removal from pulping effluents by algae  

Microsoft Academic Search

A mixed culture of algae was used to treat pulping mill effluent in terms of removing both colour and adsorbably organic\\u000a halides (AOX). The removal of AOX from pulping effluent increased with increasing initial colour value of the effluent. However,\\u000a for the total mill effluent (composed of both pulping and bleaching effluents), AOX removal was found to be independent of

F. B. Dilek; H. M. Taplamacioglu; E. Tarlan

1999-01-01

332

Biomacromolecules of Algae and Plants and their Fossil Analogues  

Microsoft Academic Search

A review of our current understanding of resistant biomacromolecules derived from present and past algae and higher plants\\u000a is presented. Insight in the nature of recent and fossil macromolecules is strongly hampered by the difficulties in obtaining\\u000a the material in pure and unaltered form. For the extant material, avoiding artificial condensation and structural alteration\\u000a as a result of chemical isolation

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

2006-01-01

333

Dynamics of photosystem II heterogeneity in Dunaliella salina (green algae)  

Microsoft Academic Search

Based on the electron-transport properties on the reducing side of the reaction center, photosystem II (PS II) in green plants and algae occurs in two distinct forms. Centers with efficient electron-transport from QA to plastoquinone (QB-reducing) account for 75% of the total PS II in the thylakoid membrane. Centers that are photochemically competent but unable to transfer electrons from QA

Jeanne E. Guenther; Anastasios Melis

1990-01-01

334

Potential of electrolytic flocculation for recovery of micro-algae  

Microsoft Academic Search

Cost-effective harvesting of micro-algae has always been a major bottle-neck not only in the exploitation of pure mass algal cultures but also in waste stabilization ponds, high rate algal ponds, and reservoirs for drinking water production. Most existing algal separation processes have several disadvantages such as intolerable costs, undesirable low dry mass percentages after harvest or algal slurries contaminated with

E. Poelman; N. De Pauw; B. Jeurissen

1997-01-01

335

2. Genome rearrangement and speciation in freshwater algae  

Microsoft Academic Search

Speciation problems are reviewed in the context of biogeography of fresh-water algae. Currently accepted species concept in\\u000a phycology is based on morphological characters, and according to this concept, most freshwater algal species are considered\\u000a cosmopolitan. This implies whether they have a highly efficient means of dispersal or their morphological characters are very\\u000a static through a long evolutionary time. Recent studies

Terunobu Ichimura

1996-01-01

336

Boron-containing organic pigments from a Jurassic red alga  

PubMed Central

Organic biomolecules that have retained their basic chemical structures over geological periods (molecular fossils) occur in a wide range of geological samples and provide valuable paleobiological, paleoenvironmental, and geochemical information not attainable from other sources. In rare cases, such compounds are even preserved with their specific functional groups and still occur within the organisms that produced them, providing direct information on the biochemical inventory of extinct organisms and their possible evolutionary relationships. Here we report the discovery of an exceptional group of boron-containing compounds, the borolithochromes, causing the distinct pink coloration of well-preserved specimens of the Jurassic red alga Solenopora jurassica. The borolithochromes are characterized as complicated spiroborates (boric acid esters) with two phenolic moieties as boron ligands, representing a unique class of fossil organic pigments. The chiroptical properties of the pigments unequivocally demonstrate a biogenic origin, at least of their ligands. However, although the borolithochromes originated from a fossil red alga, no analogy with hitherto known present-day red algal pigments was found. The occurrence of the borolithochromes or their possible diagenetic products in the fossil record may provide additional information on the classification and phylogeny of fossil calcareous algae.

Wolkenstein, Klaus; Gross, Jurgen H.; Falk, Heinz

2010-01-01

337

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

338

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

339

Population Changes in Algae- A Lesson on Ecology  

NSDL National Science Digital Library

This teaching resource was developed by a K-12 science teacher in the American Physiological Society藕s 2008 Frontiers in Physiology Program. For more information on this program, please visit www.frontiersinphys.org. Students will design and carry out an experiment where they will observe and evaluate how algae population changes when subjected to environmental influences by using a variety of detecting methods like, using a Spectrophotometer or Spec-20 for analyzing algae population density through measuring transmitted and absorbed light passing through growth tubes. An alternative analysis could be done with the assistance of a color wheel or CBL-Colorimeter Probe. This laboratory will fit into any ecology class or a unit on population changes or in any biology class unit dealing with understanding population dynamics and photosynthesis. It could be used for advanced biology classes fitting into population changes, photosynthetic studies, and food chains. Some understanding of light infiltration or absorption of light through photosynthetic organisms will assist in this laboratory. Upon completion of this activity, students will be able to enable student to collect data on living organisms using algae as templates.

2008-08-01

340

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

2011-01-01

341

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

342

Toxic effects of decomposing red algae on littoral organisms  

NASA Astrophysics Data System (ADS)

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

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

2005-03-01

343

Population dynamic of algae and bacteria in an oxidation channel.  

PubMed

A study on algae and bacteria population changes, as a function of time, was carried out in a pilot scale oxidation channel bioreactor using a carrousel system. Total Coliforms, Pseudomonas aeruginosa, and Streptococcus faecalis, the most common bacteria found in sewage, Scenedesmus obliquus and Chlorella vulgaris were the microalgae considered in this work. Physicochemical parameters such as COD, BOD, Chlorophyll a, nitrogen, and phosphorous compounds were studied and determined during the experiments. It was demonstrated that the level of wastewater contamination could be predicted based on the bacterial and algae composition. The relationships between the algae and bacteria population, and the variation of these microorganism populations as a measurement of the level of purification were established. The oxidation channel was able to remove a considerable amount of organic matter and pathogenic microorganisms in a relatively short time. The nitrification process could not be measured. The increase in the relative concentration of microalgae contributed toward improving the global efficiency of the system as well as reducing the pathogenic bacteria population. PMID:12716074

O'Farrill, N E; Travieso, L; Ben癃ez, F; B嶰ares, E; Romo, S; Borja, R; Weiland, P; S嫕chez, E

2003-04-01

344

Cadmium transport, resistance, and toxicity in bacteria, algae, and fungi.  

PubMed

Cadmium is an important environmental pollutant and a potent toxicant to bacteria, algae, and fungi. Mechanisms of Cd toxicity and resistance are variable, depending on the organism. It is very clear that the form of the metal and the environment it is studied in, play an important role in how Cd exerts its effect and how the organism(s) responds. A wide range of Cd concentrations have been used to designate resistance in organisms. To date, no concentration has been specified that is applicable to all species studied under standardized conditions. Cadmium exerts its toxic effect(s) over a wide range of concentrations. In most cases, algae and cyanobacteria are the most sensitive organisms, whereas bacteria and fungi appear to be more resistant. In some bacteria, plasmid-encoded resistance can lead to reduced Cd2+ uptake. However, some Gram-negative bacteria without plasmids are just as resistant to Cd as are bacteria containing plasmids encoding for Cd resistance. According to Silver and Misra (1984), there is no evidence for enzymatic or chemical transformations associated with Cd resistance. Insufficient information is available on the genetics of Cd uptake and resistance in cyanobacteria and algae. Mechanisms remain largely unknown at this point in time. Cadmium is toxic to these organisms, causing severe inhibition of such physiological processes as growth, photosynthesis, and nitrogen fixation at concentrations less than 2 ppm, and often in the ppb range (Tables 2 and 3). Cadmium also causes pronounced morphological aberrations in these organisms, which are probably related to deleterious effects on cell division. This may be direct or indirect, as a result of Cd effects on protein synthesis and cellular organelles such as mitochondria and chloroplasts. Cadmium is accumulated internally in algae (Table 4) as a result of a two-phase uptake process. The first phase involves a rapid physicochemical adsorption of Cd onto cell wall binding sites, which are probably proteins and (or) polysaccharides. This is followed by a lag period and then a slow, steady intracellular uptake. This latter phase is energy dependent and may involve transport systems used to accumulate other divalent cations, such as Mn2+ and Ca2+. Some data indicate that Cd resistance, and possibly uptake, in algae and cyanobacteria is controlled by a plasmid-encoded gene(s). Although considerable information is available on Cd toxicity to, and uptake in fungi, further work is clearly needed in several areas. There is little information about Cd uptake by filamentous fungi, and even in yeasts, information on the specificity, kinetics, and mechanisms of Cd uptake is limited.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:3089567

Trevors, J T; Stratton, G W; Gadd, G M

1986-06-01

345

Recovery of dairy manure nutrients by benthic freshwater algae.  

PubMed

Harnessing solar energy to grow algal biomass on wastewater nutrients could provide a holistic solution to nutrient management problems on dairy farms. The production of algae from a portion of manure nutrients to replace high-protein feed supplements which are often imported (along with considerable nutrients) onto the farm could potentially link consumption and supply of on-farm nutrients. The objective of this research was to assess the ability of benthic freshwater algae to recover nutrients from dairy manure and to evaluate nutrient uptake rates and dry matter/crude protein yields in comparison to a conventional cropping system. Benthic algae growth chambers were operated in semi-batch mode by continuously recycling wastewater and adding manure inputs daily. Using total nitrogen (TN) loading rates of 0.64-1.03 g m(-2) d(-1), the dried algal yields were 5.3-5.5 g m(-2) d(-1). The dried algae contained 1.5-2.1% P and 4.9-7.1% N. At a TN loading rate of 1.03 g m(-2) d(-1), algal biomass contained 7.1% N compared to only 4.9% N at a TN loading rate of 0.64 g m(-2) d(-1). In the best case, algal biomass had a crude protein content of 44%, compared to a typical corn silage protein content of 7%. At a dry matter yield of 5.5 g m(-2) d(-1), this is equivalent to an annual N uptake rate of 1,430 kg ha(-1) yr(-1). Compared to a conventional corn/rye rotation, such benthic algae production rates would require 26% of the land area requirements for equivalent N uptake rates and 23% of the land area requirements on a P uptake basis. Combining conventional cropping systems with an algal treatment system could facilitate more efficient crop production and farm nutrient management, allowing dairy operations to be environmentally sustainable on fewer acres. PMID:12137274

Wilkie, Ann C; Mulbry, Walter W

2002-08-01

346

Incorporation of 1-deoxy- d-xylulose into isoprene and phytol by higher plants and algae  

Microsoft Academic Search

In further substantiating the novel mevalonate-independent pathway for isoprenoid biosynthesis, which generates isopentenyl diphosphate (IPP) via 1-deoxy-d-xylulose-5-phosphate, labeling experiments with 1-[2H1]deoxy-d-xylulose were performed with various higher plants and algae: efficient incorporation was observed into isoprene emitted by Populus, Chelidonium, and Salix, into the phytol moiety of chlorophylls in a red alga (Cyanidium), in two green algae (Scenedesmus, Chlamydomonas), and a

J顤g Schwender; Johannes Zeidler; Rainer Gr霵er; Christian Mller; Manfred Focke; Siegmar Braun; Frieder W Lichtenthaler; Hartmut K Lichtenthaler

1997-01-01

347

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

348

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

349

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

350

Microbial load in mass cultures of green algae Scenedesmus acutus and its processed powder  

Microsoft Academic Search

Microbial contamination in cultures of the alga,Scenedesmus acutus raised in outdoor open tanks and also in the processed powder of the alga was monitored; The total bacterial population increased\\u000a with time during the growth period of six days. When a combination of molasses and carbondioxide was employed as carbon source\\u000a for this alga, the bacterial load increased to 10 colony

M. Mahadevaswamy; L. V. Venkataraman

1981-01-01

351

Photoreduction of mercury(II) in the presence of algae, Anabaena cylindrical  

Microsoft Academic Search

The photochemical and biological reduction of Hg(II) in the presence of algae, anabaena cylindrical, was investigated under the irradiation of metal halide lamps placed in cooling trap for maintaining constant temperature by water circulation (??365nm, 250W). The photoreduction rate of Hg(II) increased with increasing algae concentration. The addition of Fe(III) and humic substances into the suspensions of algae also enhanced

Lin Deng; Feng Wu; Nansheng Deng; Yuegang Zuo

2008-01-01

352

[Content of alginic acid and fucoidan in fucus algae of the Barents sea].  

PubMed

Seasonal changes in the content of alginic acid and fucoidan have been studied in four species of fucus algae from the Barents sea: Fucus vesiculosus, F. distichus, F. serratus, and Ascophyllum nodosum. These polysaccharides are accumulated in the biomass of the algae during summer and autumn. To ensure complete processing of fucus algae it is recommended that the raw material be harvested within this period. PMID:11962222

Obluchinskaia, E D; Voskobo?nikov, G M; Galynkin, V A

2002-01-01

353

Toxicity of Chlorate and Chlorite to Selected Species of Algae, Bacteria, and Fungi  

Microsoft Academic Search

The present study confirms that chlorate is toxic only to brown algae and not to species of other ecologically relevant taxa. The brown algaEctocarpus variabilisexhibited a LOEC of 0.005 mM (0.4 mg ClO?3\\/liter) and an LC50of 0.012 mM, when cultured with nitrate as a sole source of nitrogen. The toxicity to species other than brown algae as measured in growth

Dolf J. van Wijk; Sander G. M. Kroon; Irmgard C. M. Garttener-Arends

1998-01-01

354

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

355

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

356

Biosorption of heavy metal ions to brown algae, Macrocystis pyrifera, Kjellmaniella crassiforia, and Undaria pinnatifida  

SciTech Connect

A fundamental study of the application of brown algae to the aqueous-phase separation of toxic heavy metals was carried out. The biosorption characteristics of cadmium and lead ions were determined with brown algae, Macrocystis pyrifera, Kjellmaniella crassiforia, and Undaria pinnatifida. A metal binding model proposed by the authors was used for the description of metal binding data. The results showed that the biosorption of bivalent metal ions to brown algae was due to bivalent binding to carboxylic groups on alginic acid in brown algae.

Seki, Hideshi; Suzuki, Akira [Hokkaido Univ., Hakodate (Japan)] [Hokkaido Univ., Hakodate (Japan)

1998-10-01

357

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

358

Cycloeudesmol, an Antibiotic Cyclopropane Containing Sesquiterpene from the Marine Alga, 'Chondria oppositiclada' Dawson.  

National Technical Information Service (NTIS)

Chondria oppositiclada Dawson, a marine algae produces cyclopropane containing sesquiterpene alcohol, cycloeudesmol. Cycloeudesmol is strongly antibiotic toward Staphylococcus aureus and Candida albicans.

W. Fenical J. J. Sims

1973-01-01

359

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...

360

Survival and reproduction in some algae under stress conditions.  

PubMed

Pithophora oedogonia and Cladophora glomerata survived lowest 60 and 58%, respectively, in June when the pond diurnal water temperature (PDWT) increased to a maximum of 28 degrees C. The lowering of PDWT only by 1 degrees C in July improved survivability of both algae to their almost maximum level of 100 and 96%, respectively. Further lowering of PDWT to 17-22 degrees C in November initiated akinete formation in P. oedogonia. The process of akinete initiation, maturation and germination continued till April when PDWT increased to 20-24 degrees C, but not beyond that in May when PDWT was 21-26 degrees C. By this time, probably all akinetes have germinated in situ, and the alga was entirely vegetative. P. oedogonia population is not synchronous in nature, since during the 5-6-month reproductive season, some filaments were in active vegetative stage, some had akinete initiation, some had completed akinete formation, and some had akinetes germinating. C. glomerata grew dense vegetative in November and initiated (zoo)sporangial primordia formation (to some extent) in February (when PDWT was lowest, viz. 10-14 degrees C) till April. Meanwhile, no (zoo)-sporangial primordia either produced any zoospore or germinated into a germ tube; and all released their cytoplasmic content and died (along with some vegetative cells) with an increase in PDWT to 21-26 degrees C in May. Vaucheria geminata vegetative patches appeared on the soil surface, 2nd week of January by lowering of atmospheric diurnal temperature (ADT) to 9-16 degrees C in the 1st week. The alga started sexual reproduction by the 2nd week of March (when ADT increased to 20-23 degrees C) and completed the process of reproduction by the 1st week of April (when ADT increased to 24-26 degrees C) and died thereafter. P. oedogonia, C. glomerata and V. geminata survived better and longer in submerged conditions than air-exposed (which was true for P. oedogonia and C. glomerata aquatic habitat and also indicated that the soil alga V. geminata could survive to some extent if submerged in rain water). P. oedogonia formed akinetes and C. glomerata (zoo)sporangial primordia only in submerged condition and not when air-exposed on moist soil surface. V. geminata did not complete the life cycle both under submerged and air-exposed conditions. Vegetative survival in P. oedogonia, C. glomerata, V. geminata, Aphanothece pallida, Gloeocapsa atrata, Scytonema millei, Myxosarcina burmensis, Phormidium bohneri, Oscillatoria animalis, O. subbrevis, Lyngbya birgei, L. major, Microcoleus chthonoplastes and Rhizoclonium crassipellitum, reproduction in P. oedogonia, C. glomerata and V. geminata, cell division in A. pallida and G. atrata, heterocyst and false branch formation in S. millei, all, were adversely affected at approximately 28.5 degrees C for t12 h at light intensity of approximately 160 micromol m(-2) s(-1); high intensity does not ameliorate high temperature damage to any algae. The presence of liquid water, than its absence, outside the different algae moderated the severity of heat to some extent but not when the heat was severe. PMID:18450223

Gupta, S; Agrawal, S C

2007-01-01

361

Multispectral sorter for rapid, nondestructive optical bioprospecting for algae biofuels  

NASA Astrophysics Data System (ADS)

Microalgal biotechnology is a nascent yet burgeoning field for developing the next generation of sustainable feeds, fuels, and specialty chemicals. Among the issues facing the algae bioproducts industry, the lack of efficient means of cultivar screening and phenotype selection represents a critical hurdle for rapid development and diversification. To address this challenge, we have developed a multi-modal and label-free optical tool which simultaneously assesses the photosynthetic productivity and biochemical composition of single microalgal cells, and provides a means for actively sorting attractive specimen (bioprospecting) based on the spectral readout. The device integrates laser-trapping micro-Raman spectroscopy and pulse amplitude modulated (PAM) fluorometry of microalgal cells in a flow cell. Specifically, the instrument employs a dual-purpose epi-configured IR laser for single-cell trapping and Raman spectroscopy, and a high-intensity VISNIR trans-illumination LED bank for detection of variable photosystem II (PSII) fluorescence. Micro-Raman scatter of single algae cells revealed vibrational modes corresponding to the speciation and total lipid content, as well as other major biochemical pools, including total protein, carbohydrates, and carotenoids. PSII fluorescence dynamics provide a quantitative estimate of maximum photosynthetic efficiency and regulated and non-regulated non-photochemical quenching processes. The combined spectroscopic readouts provide a set of metrics for subsequent optical sorting of the cells by the laser trap for desirable biomass properties, e.g. the combination of high lipid productivity and high photosynthetic yield. Thus the device provides means for rapid evaluation and sorting of algae cultures and environmental samples for biofuels development.

Davis, Ryan W.; Wu, Hauwen; Singh, Seema

2014-03-01

362

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

363

The ecology of viruses that infect eukaryotic algae.  

PubMed

Because viruses of eukaryotic algae are incredibly diverse, sweeping generalizations about their ecology are rare. These obligate parasites infect a range of algae and their diversity can be illustrated by considering that isolates range from small particles with ssRNA genomes to much larger particles with 560?kb dsDNA genomes. Molecular research has also provided clues about the extent of their diversity especially considering that genetic signatures of algal viruses in the environment rarely match cultivated viruses. One general concept in algal virus ecology that has emerged is that algal viruses are very host specific and most infect only certain strains of their hosts; with the exception of viruses of brown algae, evidence for interspecies infectivity is lacking. Although some host-virus systems behave with boom-bust oscillations, complex patterns of intraspecies infectivity can lead to host-virus coexistence obfuscating the role of viruses in host population dynamics. Within the framework of population dynamics, host density dependence is an important phenomenon that influences virus abundances in nature. Variable burst sizes of different viruses also influence their abundances and permit speculations about different life strategies, but as exceptions are common in algal virus ecology, life strategy generalizations may not be broadly applicable. Gaps in knowledge of virus seasonality and persistence are beginning to close and investigations of environmental reservoirs and virus resilience may answer questions about virus inter-annual recurrences. Studies of algal mortality have shown that viruses are often important agents of mortality reinforcing notions about their ecological relevance, while observations of the surprising ways viruses interact with their hosts highlight the immaturity of our understanding. Considering that just two decades ago algal viruses were hardly acknowledged, recent progress affords the optimistic perspective that future studies will provide keys to unlocking our understanding of algal virus ecology specifically, and aquatic ecosystems generally. PMID:22360532

Short, Steven M

2012-09-01

364

[Epiphytic algae from Bajo Pepito, Isla Mujeres, Quintana Roo, Mexico].  

PubMed

A total of 96 epiphytic algae species were identified from Bajo Pepito, Quintana Roo, M憖ico. 60.4% (58) belonged to the Rhodophyta, 19.79% (19) to the Phaeophyta, 16.6% (16) to the Chlorophyta and 3.1% (3) to the Cyanophyta; 49 species (50.5%) were found only in one month, while Heterosiphonia crispella was found in all of the sampled months. That species provided the largest contribution to the biomass of epiphytes. During January we registered the greater biommass and richness of epiphytes species, coincidently with high values of host species cover and rainfall. PMID:18494302

Quan-Young, L I; D燰z-Mart璯, M A; Espinoza-Avalos, J

2006-06-01

365

Fibrinolytic Compounds Isolated from a Brown Alga, Sargassum fulvellum  

PubMed Central

Two of bioactive natural products were founded in a brown alga, Sargassum fulvellum. After isolation and purification, the molecular structures of these two products were investigated by NMR spectroscopy and GC-mass spectroscopy. The two compounds were identified to be 1-O-palmitoyl-2-O-oleoyl-3-O-(?-D-glucopyranosyl) glycerol (POGG) and 1-O-myristoyl-2-O-oleoyl-3-O-(?-D-glucopyranosyl) glycerol (MOGG) which were obtained from Sargassum fulvellum for the first time. POGG and MOGG showed fibrinolytic activity in the reaction system of pro-u-PA and plasminogen.

Wu, Wenhui; Hasumi, Keiji; Peng, Hui; Hu, Xianwen; Wang, Xichang; Bao, Bin

2009-01-01

366

Toxicity of oxide nanoparticles to the green algae Chlorella sp  

Microsoft Academic Search

Increasing studies focus on nanotoxicity, but many unknowns are remaining to be investigated. This study examined toxicities of four varieties of oxide nanoparticles (Al2O3, SiO2, ZnO, and TiO2) to the green algae Chlorella sp. Nanoparticulate Al2O3, SiO2, and TiO2 (DJ3, rutile) had no significant toxicity, whereas nano-ZnO and nano-TiO2 (HR3, anatase) greatly inhibited the algal growth with 6d EC30 of

Jing Ji; Zhifeng Long; Daohui Lin

2011-01-01

367

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

368

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

369

Interaction of organic solvents with the green alga Chlorella pyrenoidosa  

SciTech Connect

Solvents are often a component of bioassay systems when water-insoluble toxicants are being tested. These solvents must also be considered as xenobiotics and therefore, as potential toxicants in the bioassay. However, the effects of solvents on the organisms being tested and their possible interaction with the test compound are often overlooked by researchers. The purpose of the present study was to compare the inhibitory effects of six solvents commonly used in pesticide bioassays towards growth of the common green alga Chlorella pyrenoidosa, and to examine the occurrence of solvent-pesticide interactions with this organism.

Stratton, G.W.; Smith, T.M. (Nova Scotia Agricultural College, Truro (Canada))

1988-06-01

370

The chemical constituents from red alga Gymnogongrus flabelliformis Harv.  

NASA Astrophysics Data System (ADS)

Eight compounds were isolated from red alga Gymnogongrus flabelliformis Harv. In normal phase silica gel, Sephadex LH-20 gel column chromatography, reverse phase HPLC, and recrystallization. Based on MS and 1D NMR spectroscopic data, their structures were determined as: stigmast-4-en-3-one (I), cholest-4-en-3-one (II), cholesterol (III), uracil (IV), uridine (V), adenosine (VI), succinic acid (VII), and 5-hydroxy-4-methyl-5-pentyl-2,5-dihydro-furan-2-on (VIII ). All of them were obtained from this species for the first time. Cytotoxicity of these compounds was screened using standard MTT method, but all the compounds were inactive (IC50 > 10 ?g/ml).

Yuan, Zhaohui; Han, Lijun; Su, Hua; Shi, Dayong; Sun, Jie; Li, Shuai; Shi, Jiangong

2008-05-01

371

ALTERNATIVE WATER DISINFECTION SCHEMES FOR REDUCED TRIHALOMETHANE FORMATION. VOLUME 2. ALGAE AS PRECURSORS FOR TRIHALOMETHANES IN CHLORINATED DRINKING WATER  

EPA Science Inventory

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 separated from the extracellula...

372

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

373

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

374

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

2013-01-01

375

Acute exudative tonsillitis caused by Shewanella algae in a healthy child.  

PubMed

Shewanella algae, mainly found in marine environments, is a rare pathogen in humans, especially in healthy children. Here we report a previously healthy boy presenting with acute exudative tonsillitis after traveling to the coast, and S. algae was isolated from the throat swab culture. PMID:17148087

Liu, Min-Chang; Gau, Shiow-Jen; Wu, Hsien-Cheng

2006-01-01

376

Characterization of a sugar\\/polyol uptake system in the red alga Galdieria sulphuraria  

Microsoft Academic Search

The unicellular, acido- and thermophilic red alga Galdieria sulphuraria is unique in its ability to grow heterotrophically on at least 27 different sugars and polyols. The enzymatic machinery necessary for metabolizing this variety of compounds is constitutively expressed in the alga. The uptake system, however, has to be induced. From in vivo studies we conclude that the uptake system consists

Christine Oesterhelt; Claus Schnarrenberger; Wolfgang Gross

1999-01-01

377

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

378

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

379

Microbiological treatment of industrial wastes containing toxic chromium involving successive use of bacteria, yeast and algae  

Microsoft Academic Search

Bacteria, yeasts, protozoa and algae, observed in industrial effluents from tanneries, were checked for their possible use in the detoxification of polluted water. Two bacterial strains were found to be highly resistant to CrVI. Several bacteria, yeasts and algae were observed to be capable of reducing CrVI to CrIII.

R. ul Haq; A. R. Shakoori

1998-01-01

380

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

381

Proton and metal binding capacity of the green freshwater alga Chaetophora elegans  

Microsoft Academic Search

A biomass for removing heavy metal ions from aqueous solutions has been investigated. The green alga Chaetophora elegans was characterized in terms of the number of binding sites and proton binding constant by potentiometric titration in different ionic media. The discrete site distribution model used, considering the algae cells suspensions as a mixture of monoprotic acids, allowed the characterisation of

A. D. Andrade; M. C. E. Rollemberg; J. A. N鏏rega

2005-01-01

382

Fucoxanthin and Its Metabolites in Edible Brown Algae Cultivated in Deep Seawater  

PubMed Central

Three metabolites of fucoxanthin were isolated from a brown alga, Scytosiphon lomentaria, and the structure of a new compound was determined by NMR. The content of fucoxanthin, a biologically active carotenoid, in four edible brown algae, cultivated in deep seawater, was studied.

Mori, Kanami; Ooi, Takashi; Hiraoka, Masanori; Oka, Naohiro; Hamada, Hideyuki; Tamura, Mitsumasa; Kusumi, Takenori

2004-01-01

383

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. ...

384

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

385

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

386

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

NASA Technical Reports Server (NTRS)

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.

Oehler, J. H.; Schopf, J. W.

1971-01-01

387

The distribution and abundance of algae in saline lakes of Saskatchewan, Canada  

Microsoft Academic Search

Collections of algae, mainly planktonic, were made from 41 saline lakes in southern Saskatchewan ranging in salinity from 3.2 to 428 g l-1. Algae in 7 phyla, 8 classes, 42 families, 91 genera and 212 species and varieties were identified. Fourteen species were restricted to hypersaline (50 g l-1) waters and eleven of these were diatoms. In general, species diversity

U. T-heodore Hammer; Jennifer Shamessl; Robert C. Haynes

1983-01-01

388

Ingestion, assimilation, survival, and reproduction by Daphnia pulex fed seven species of blue-green algae  

Microsoft Academic Search

Daphnia p&x (Crustacea, Cladocera) was fed the blue-green algae (Cyanophyceae) Anacystis nidulans, Synechococcus elongata, S. cedrorum, Merismopedia sp., Anabaena flos- aquae, Synechocystis sp., and Gloeocapsa alpicola. The green algae ( Chlorophyceae) Ankis- trodesmus falcatus and Chlorella uulgaris were used for comparison. Direct observations were made of D. pulex feeding in depression slides filled with the test food. Food labeled with

DEAN E. ARNOLD

1971-01-01

389

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 ...

390

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

391

Development of a ground-based space micro-algae photo-bioreactor  

Microsoft Academic Search

The purpose of the research is to develop a photo-bioreactor which may produce algae protein and oxygen for future astronauts in comparatively long-term exploration, and remove carbon dioxide in a controlled ecological life support system. Based on technical parameters and performance requirements, the project planning, design drafting, and manufacture were conducted. Finally, a demonstration test for producing algae was done.

W. Ai; S. Guo; L. Qin; Y. Tang

2008-01-01

392

Controlled artificial upwelling in a fjord to stimulate non-toxic algae  

Microsoft Academic Search

During the summer, primary production in the surface layers of some fjords depletes the nutrients to the degree that some species of toxic algae can dominate. We describe field experiments employing a bubble curtain and a submerged freshwater outlet to lift significant amounts of nutrient-rich seawater to the light zone to provide an environment in which non-toxic algae can bloom.

T. A. McClimans; A. Hand; A. Fredheim; E. Lien; K. I. Reitan

2010-01-01

393

Contact Inhibition: Also a Control for Cell Proliferation in Unicellular Algae?  

Microsoft Academic Search

According to traditional views, the prolifera- tion of unicellular algae is controlled primarily by envi- ronmental conditions. But as in mammalian cells, other biological mechanisms, such as growth factors, cellular aging, and contact inhibition, might also control algal proliferation. Here we ask whether contact inhibition reg- ulates growth in several species of unicellular algae as it does in mammalian cells.

EDUARDO COSTAS; ANGELES AGUILERA; SONSOLES GONZALEZ-GIL; VICTORIA LdPEZ-RODAS

394

Potential Role of Marine Algae on Female Health, Beauty, and Longevity  

Microsoft Academic Search

Marine environment has been known as a rich source of chemical structures with numerous health benefit effects. Among marine organisms, marine algae have been identified as an underexploited 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 of marine algae in promoting

Se-Kwon Kim; Ratih Pangestuti

2011-01-01

395

Artificial Life Simulation of Living Alga Cells and Its Sorption Mechanisms  

Microsoft Academic Search

Resistance mechanisms of organisms against toxic metals are based on a few different mechanisms provided by algae cells. These mechanisms can be localized on the cell wall, on the cell wall and cytoplasm membrane, and intracellular localized mechanisms. Due to these mechanisms, algae populations could be used for sorption of arsenic from contaminated waters. This process takes a long time

Julius Csonto; Jana Kadukova; Marek Polak

2001-01-01

396

Manganese uptake and Mn(II) oxidation by the alga Scenedesmus subspicatus  

Microsoft Academic Search

To examine the relationships among manganese concentration in the culture medium, algae growth, manganese uptake and Mn(II) oxidation on the algal surface, we exposed the unicellular alga Scenedesmus subspicatus to a broad range of free Mn2+ ion concentrations. Extra- and intracellular manganese concentrations were distinguished by reducing the Mn oxides with ascorbate. A large fraction of the Mn bound by

Katja Knauer; Thomas Jabusch; Laura Sigg

1999-01-01

397

Variability and abundance of the epiphytic bacterial community associated with a green marine Ulvacean alga  

Microsoft Academic Search

Marine Ulvacean algae are colonized by dense microbial communities predicted to have an important role in the development, defense and metabolic activities of the plant. Here we assess the diversity and seasonal dynamics of the bacterial community of the model alga Ulva australis to identify key groups within this epiphytic community. A total of 48 algal samples of U. australis

Niina A Tujula; Gregory R Crocetti; Catherine Burke; Torsten Thomas; Carola Holmstr闣; Staffan Kjelleberg

2010-01-01

398

Structure and molecular organization of the photosynthetic accessory pigments of cyanobacteria and red algae  

Microsoft Academic Search

Cyanobacteria (blue-green algae) and Rhodophyta (red algae) contain high concentrations of photosynthetic accessory pigments (phycobiliproteins) which trap light energy in the region between 400 and 650 nm. The electronic excitation energy is then transferred along a chain of these pigments to the reaction center chlorophyll of Photosystem II by a radiationless induced resonance process.

Alexander N. Glazer

1977-01-01

399

A biomonitoring study: trace metals in algae and molluscs from Tyrrhenian coastal areas  

Microsoft Academic Search

Marine organisms were evaluated as possible biomonitors of heavy metal contamination in marine coastal areas. Concentrations of Cd, Cr, Cu, Pb, and Zn were measured in the green algae Ulva lactuca L., the brown algae Padina pavonica (L.) Thivy, the bivalve mollusc Mytilus galloprovincialis Lamarck, and the two gastropod molluscs Monodonta turbinata Born and Patella cerulea L. collected at six

Marcelo Enrique Conti; Gaetano Cecchetti

2003-01-01

400

Recycling algae to improve species control and harvest efficiency from a high rate algal pond  

Microsoft Academic Search

This paper investigates the influence of recycling gravity harvested algae on species dominance and harvest efficiency in wastewater treatment High Rate Algal Ponds (HRAP). Two identical pilot-scale HRAPs were operated over one year either with (HRAPr) or without (HRAPc) harvested algal biomass recycling. Algae were harvested from the HRAP effluent in algal settling cones (ASCs) and harvest efficiency was compared

J. B. K. Park; R. J. Craggs; A. N. Shilton

401

Organic matter release by coral reef associated benthic algae in the Northern Red Sea  

Microsoft Academic Search

Recent research indicates that coral reef associated benthic algae may control important metabolic processes in reef ecosystems via organic matter release. Yet little information is available about quantity and chemical composition of these algae-derived exudates. Therefore first comprehensive studies on algal organic matter release were conducted at a fringing reef ecosystem in the Northern Red Sea. Dissolved organic carbon (DOC),

Andreas F. Haas; Malik S. Naumann; Ulrich Struck; Christoph Mayr; Mohammad el-Zibdah; Christian Wild

2010-01-01

402

Life history characteristics of three types of females in Brachionus calyciflorus Pallas (Rotifera) fed different algae  

Microsoft Academic Search

This study describes the life history characteristics of amictic, unfertilized mictic and fertilized mictic females of the rotifer Brachionus calyciflorus cultured individually on two different algae at 0.1 mg ml-1 food concentration and 27 蚓. The duration of the juvenile period of amictic females was significantly shorter on Chlorella pyrenoidosa Chick than on Scenedesmus obliquus Ktz or both algae together.

Yi-Long Xi; Xiang-Fei Huang; Hong-Jun Jin

2001-01-01

403

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

2012-04-22

404

Combustion of algae oil methyl ester in an indirect injection diesel engine  

Microsoft Academic Search

An experimental study has been carried to use raw Algae oil and its methyl esters in an indirect injection diesel engine. Effects of engine speed, engine load output, injection timing of the algae biofuel and engine compression ratio on the engine output torque, combustion noise (maximum pressure rise rate), maximum pressure and maximum heat release rate have been studied. Raw

Yousef Haik; Mohamed Y. E. Selim; Tahir Abdulrehman

2011-01-01

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

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

407

Naphthenic acid biodegradation by the unicellular alga Dunaliella tertiolecta.  

PubMed

Naphthenic acids (NAs) are a major contributor to toxicity in tailings waste generated from bitumen production in the Athabasca Oil Sands region. While investigations have shown that bacteria can biodegrade NAs and reduce tailings toxicity, the potential of algae to biodegrade NAs and the biochemical mechanisms involved remain poorly understood. Here, we discovered that the marine alga Dunaliella tertiolecta is able to tolerate five model NAs (cyclohexanecarboxylic acid, cyclohexaneacetic acid, cyclohexanepropionic acid, cyclohexanebutyric acid and 1,2,3,4-tetrahydro-2-naphthoic acid) at 300mgL(-1), a level which exceeds that of any single or combination of NAs typically found in tailings ponds. Moreover, we show that D. tertiolecta can metabolize four of the model NAs. Analysis of NA-amended cultures of D. tertiolecta via low resolution gas chromatography-mass spectrometry allowed us to quantify decreasing NA levels, identify metabolites, and formulate putative mechanisms of biodegradation. Degradation of cyclohexanebutyric acid and cyclohexanepropionic acid proceeded via ?-oxidation and resulted in the transient accumulation of cyclohexaneacetic acid and cyclohexanecarboxylic acid, respectively. Cyclohexanecarboxylic acid was metabolized via 1-cyclohexenecarboxylic acid suggesting that further degradation may occur by step-wise ?-oxidation. When D. tertiolecta was inoculated in the presence of oil sands tailings water from the Athabasca region, biodegradation of single-ring NAs was observed relative to controls. This result corroborates the trend we observed with the single-ring model NAs. PMID:21459409

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

2011-07-01

408

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

409

Irradiance-mediated dimethylsulphoniopropionate (DMSP) responses of red coralline algae  

NASA Astrophysics Data System (ADS)

Red coralline algae produce significant quantities of dimethylsulphoniopropionate (DMSP), whose breakdown products include the important climate gas dimethylsulphide (DMS) but little is known about how environmental factors influence this DMS(P) production. The effect of photosynthetically active radiation (PAR) on intracellular DMS(P) concentrations in the red coralline algae Lithothamnion glaciale was investigated using short (30 min) and longer-term (up to 507 h) acclimatory responses and control and high-PAR light regimes. Longer-term acclimatory intracellular DMS(P) concentrations were significantly reduced following exposure to high-PAR (220-250 ?mol m -2 s -1). No short-term acclimatory effects were observed. We conclude that while DMS(P) content in L. glaciale does respond to changes in irradiance, the effect takes place over hours - days rather than minutes, suggesting a continued turnover of DMS(P) to combat oxidative stress induced by prolonged high-PAR exposure. Immediate short-term acclimatory responses do not appear to occur.

Rix, L. N.; Burdett, H. L.; Kamenos, N. A.

2012-01-01

410

Polyploidy of Endosymbiotically Derived Genomes in Complex Algae  

PubMed Central

Chlorarachniophyte and cryptophyte algae have complex plastids that were acquired by the uptake of a green or red algal endosymbiont via secondary endosymbiosis. The plastid is surrounded by four membranes, and a relict nucleus, called the nucleomorph, remains in the periplastidal compartment that is the remnant cytoplasm of the endosymbiont. Thus, these two algae possess four different genomes in a cell: Nuclear, nucleomorph, plastid, and mitochondrial. Recently, sequencing of the nuclear genomes of the chlorarachniophyte Bigelowiella natans and the cryptophyte Guillardia theta has been completed, and all four genomes have been made available. However, the copy number of each genome has never been investigated. It is important to know the actual DNA content of each genome, especially the highly reduced nucleomorph genome, for studies on genome evolution. In this study, we calculated genomic copy numbers in B. natans and G. theta using a real-time quantitative polymerase chain reaction approach. The nuclear genomes were haploid in both species, whereas the nucleomorph genomes were estimated to be diploid and tetraploid, respectively. Mitochondria and plastids contained a large copy number of genomic DNA in each cell. In the secondary endosymbioses of chlorarachniophytes and cryptophytes, the endosymbiont nuclear genomes were highly reduced in size and in the number of coding genes, whereas the chromosomal copy number was increased, as in bacterial endosymbiont genomes. This suggests that polyploidization is a general characteristic of highly reduced genomes in broad prokaryotic and eukaryotic endosymbionts.

Hirakawa, Yoshihisa; Ishida, Ken-Ichiro

2014-01-01

411

Interest of dynamic tests in acute ecotoxicity assessment in algae  

SciTech Connect

Sorption of toxics by algae may be important and occurs very early. Thus, a decrease of the experimental toxic concentrations in the medium results in understating toxicity when tests are conducted under static conditions. In this work, two different methods of exposure of algae (Chlorella vulgaris) are studied, the static test and the pseudodynamic test. Acute effects (biological and analytical effects) of inorganic compounds (Cu/sup 2 +/, Cd/sup 2 +/, Pb/sup 2 +/, Cr/sup 6 +/) have been evaluated for 96 hr of exposure; in each case, IC50 is much lower in the dynamic condition than in the static one. The percentage of reduction varies from 55 to 75% after 96 hr. Accumulation of metal by chlorellae is greater when testing by the pseudodynamic way, with Cu/sup 2 +/ and Pb/sup 2 +/. But in the case of Cd/sup 2 +/ and Cr/sup 6 +/, the concentration factors are similar in the two kinds of exposure. These results point out the advantage of the pseudodynamic test, of which the methodology is very easy, for a more realistic assessment of acute ecotoxicity in these organisms.

Jouany, J.M.; Ferard, J.F.; Vasseur, P.; Gea, J.; Truhaut, R.; Rast, C.

1983-04-01

412

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

413

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

414

Halophytes, Algae, and Bacteria Food and Fuel Feedstocks  

NASA Technical Reports Server (NTRS)

The constant, increasing demand for energy, freshwater, and food stresses our ability to meet these demands within reasonable cost and impact on climate while sustaining quality of life. This environmental Triangle of Conflicts between energy, food, and water--while provoked by anthropogenic monetary and power struggles--can be resolved through an anthropogenic paradigm shift in how we produce and use energy, water, and food. With world population (6.6 billion) projected to increase 40 percent in 40 to 60 yr, proper development of saline agriculture and aquaculture is required, as 43 percent of the Earth's landmass is arid or semi-arid and 97 percent of the Earth's water is seawater. In light of this, we seek fuel alternatives in plants that thrive in brackish and saltwater with the ability to survive in arid lands. The development and application of these plants (halophytes) become the primary focus. Herein we introduce some not-so-familiar halophytes and present a few of their benefits, cite a few research projects (including some on the alternatives algae and bacteria), and then set theoretical limits on biomass production followed by projections in terms of world energy demands. Based on diverse arid lands with a total size equivalent to the Sahara Desert (8.6(exp 8) ha, or 2.1(exp 9) acres), these projections show that halophyte agriculture and algae systems can provide for the projected world energy demand.

Hendricks, R. C.; Bushnell, D. M.

2009-01-01

415

Polyploidy of endosymbiotically derived genomes in complex algae.  

PubMed

Chlorarachniophyte and cryptophyte algae have complex plastids that were acquired by the uptake of a green or red algal endosymbiont via secondary endosymbiosis. The plastid is surrounded by four membranes, and a relict nucleus, called the nucleomorph, remains in the periplastidal compartment that is the remnant cytoplasm of the endosymbiont. Thus, these two algae possess four different genomes in a cell: Nuclear, nucleomorph, plastid, and mitochondrial. Recently, sequencing of the nuclear genomes of the chlorarachniophyte Bigelowiella natans and the cryptophyte Guillardia theta has been completed, and all four genomes have been made available. However, the copy number of each genome has never been investigated. It is important to know the actual DNA content of each genome, especially the highly reduced nucleomorph genome, for studies on genome evolution. In this study, we calculated genomic copy numbers in B. natans and G. theta using a real-time quantitative polymerase chain reaction approach. The nuclear genomes were haploid in both species, whereas the nucleomorph genomes were estimated to be diploid and tetraploid, respectively. Mitochondria and plastids contained a large copy number of genomic DNA in each cell. In the secondary endosymbioses of chlorarachniophytes and cryptophytes, the endosymbiont nuclear genomes were highly reduced in size and in the number of coding genes, whereas the chromosomal copy number was increased, as in bacterial endosymbiont genomes. This suggests that polyploidization is a general characteristic of highly reduced genomes in broad prokaryotic and eukaryotic endosymbionts. PMID:24709562

Hirakawa, Yoshihisa; Ishida, Ken-Ichiro

2014-04-01

416

Identifying vital effects in Halimeda algae with Ca isotopes  

NASA Astrophysics Data System (ADS)

Geochemical records of biogenic carbonates provide some of the most valuable records of the geological past, but are often difficult to interpret without a mechanistic understanding of growth processes. In this experimental study, Halimeda algae are used as a test organism to untangle some of the specific factors that influence their skeletal composition, in particular their Ca-isotope composition. Algae were stimulated to precipitate both calcite and aragonite by growth in artificial Cretaceous seawater. The Ca-isotope fractionation of the algal calcite is much smaller than that for the algal aragonite, similar to the behaviour observed in inorganic precipitates. However, the carbonate from Halimeda is isotopically heavier than inorganic forms, likely due to Rayleigh distillation within the algal intercellular space. In identifying specific vital effects and the magnitude of their influence on Ca-isotope ratios, this study suggests that mineralogy has a first-order control on the Ca-isotope budget of the carbonate sink and the Ca-isotope composition of seawater.

Bl酹tler, C. L.; Stanley, S. M.; Henderson, G. M.; Jenkyns, H. C.

2014-03-01

417

[Extinguishment of harmful algae by organo-clay].  

PubMed

Periodic and widespread algal blooms have caused a variety of problems for aquatic life and human activity throughout the world. Currently, the only remedial practice employed for removing algal blooms is to spread clay on the surface of the water. But, the algal removal efficiency by the crude minerals are not really ideal, and how to improve the capability of clays to remove algae is now the technological focus, which also is fatal to the practical value of clays. In this study, hexadecyltrimethyleamine bromide (HDTMAB), one kind of cationic organo-surfactants, was chosen to improve kaolin by surface sorption and cationic exchange, and was tested to remove Prorocentrum donghaiense, a red tide organism in Donghai Sea. The results indicated that organo-clay had an excellent ability to extinguish red tide organisms, even under the application of 0.01 g.L-1, and could subside more than 95% red tide organisms in 24 h. The efficient algae removal by organo-clay might be from the reversal of the surface electric charge on clay particles, the "net capture" by the long lipoid chains of HDTMAB, and the local high density of HDTMAB on particles surface, which could effectively kill algal cells. PMID:14587345

Cao, Xihua; Yu, Zhiming

2003-07-01

418

The algae raceway integrated design for optimal temperature management  

SciTech Connect

The Algae Raceway Integrated Design (ARID) minimizes diurnal and seasonal temperature fluctuations and maintains temperature within the optimal range, between 15 and 30 #1;C, during day and night and during all seasons in Tucson, Arizona. The system regulates temperature by adjusting the water surface area and thus regulates the energy transfer to and from the atmosphere and raceway. A temperature model of the raceway was developed and was based on a standardized energy balance model for agricultural crops. The model includes the PenmaneMonteith evapotranspiration equation, long wave radiation, short wave radiation, sensible heat transfer (convection) and soil heat flux. The temperature model predicted minimum daily raceway water temperature within 1-2 蚓 over a range of atmospheric conditions during a 21 day algae growth experiment. Because the model is based on standard agricultural weather station data, it can be used in any location that is in proximity to an agricultural weather station. The model automatically downloads data from any weather station in Arizona, allows specification of various cover and liner conditions, specifies the timing of circulation, and has a dynamic simulation mode.

Waller, P. [University of Arizona; Ryan, R. [University of Arizona; Kacira, M. [University of Arizona; Li, Peiwen [University of Arizona

2012-01-01

419

Composition, structural characteristics, and antitumor properties of polysaccharides from the brown algae Dictyopteris polypodioides and Sargassum sp  

Microsoft Academic Search

The polysaccharide compositions of the brown algae Dictyopteris polypodioides and Sargassum sp. from the Mediterranean Sea were determined. The principal polysaccharide of the studied algae (about 12% of the dry alga\\u000a weight) was alginic acid. The content of water-soluble polysaccharides was low. The amount of fucoidan was less than 1% of\\u000a the dry alga weight; of neutral polysaccharides, less than

R. V. Sokolova; S. P. Ermakova; S. M. Awada; T. N. Zvyagintseva; H. M. Kanaan

2011-01-01

420

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

421

Monitoring experiment and analysis of blue-green algae waterbloom in Chaohu Lake by NOAA satellite  

NASA Astrophysics Data System (ADS)

Algal chlorophyll measurement is usually used to assess trophic status of lakes. The development of satellite remote sensing technology make it possible to detect spectral features of algal chlorophyll and to map the spatial distribution of algae in large lakes. In this paper, NOAA satellite data were utilized to monitor the blue-green algae waterbloom in Chaohu Lake, together with the water sampling for concentrations of chlorophhyll-a analysis and spectral measuring simultaneously. The result indicates that: if there are chlorophylls of blue-green algae, the water reflectance in the near infrared band will obviously increase. Based on this spectral characteristic and the features of blue-green algae' float, meteorological satellite NOAA/AVHRR data can be used to monitor the blue-green algae waterbloom in large badly contaminated inland lakes.

Hu, Wen; Yang, Shizhi; Zhai, Wuquan; Zhou, Kun; Huang, Yong

2003-05-01

422

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

423

[Mechanism of the inhibitory action of allelochemical dibutyl phthalate on algae Gymnodinium breve].  

PubMed

The aim of this study was to investigate the mechanism of inhibitory action of dibutyl phthalate (DBP) on red tide algae Gymnodinium breve. The effects of DBP on malonaldehyde, subcellular structure and superoxide dismutase (SOD) isoforms were investigated. The results showed that MDA accumulated in the algae cell under DBP exposure, and for the 3 mg x L(-1) DBP treated algae culture a peak value of 0.34 micromol x (10(9) cells) (-1) occurred at 72 h, which was about 2. 3 times than that of the control. TEM pictures showed the disruption of DBP on the subcellular structure of G. breve. A morphological phenomenon appeared that the algae cell was commonly found small tubules or apical parts around the cell membrane, and almost all normal cell organelles were indistinguishable finally. The activity of CuZn-SOD (main cytoplast located isoform with little in cloroplast) under DBP exposure was higher than that of the control, and no significant difference was observed on Fe-SOD (chloroplast located isoform) activity, but for the Mn-SOD (mitochondrial isoform), the activity was significantly inhibited. These results indicated that DBP might inhibit the algae growth from the plasma membrane and the mitochondria, resulting in oxidative damage in algae cell and a final death. This paper will give a theoretical support to the practical usage of the allelochemical on red tide algae. PMID:22452215

Bie, Cong-Cong; Li, Feng-Min; Wang, Yi-Fei; Wang, Hao-Yun; Zhao, Ya-Han; Zhao, Wei; Wang, Zhen-Yu

2012-01-01

424

Distribution and paleoecology of algae from Missourian (Upper Pennsylvanian) cyclic sequences, Mid-Continent, USA  

SciTech Connect

The objectives of this study are fourfold: (1) document the basinal to inner shelf and vertical distribution of marine algae from Missourian transgressive-regressive depositional sequences of the U.S. Mid-Continent: (2) integrate observed taphonomic and petrographic properties with the distribution patterns to produce empirically derived paleoecologic interpretations of these algae; (3) propose an algal-carbonate facies model for Upper Pennsylvanian depositional sequences; (4) indicate which facies could be potential reservoirs. Preliminary results indicate that cyanobacteria, often intergrown with encrusting forams, are as abundant as oncoids and encrustations; this consortia is often associated with the encrusting rhodophyte Archaeolithophyllum lamellosum, creating boundstone hardgrounds. These algae are especially characteristic of transgressive/highstand shelf and basin facies, are not commonly associated with other calcareous algal groups, and are low-light tolerant. The rhodophyte phylloid alga A. missouriense occurs as large prostrate blades in mudstones, as in situ broken blades with abundant isopachous and botryoidal fibrous cements and mudstone breccia, or as abraded fragments in grainstones associated with various chlorophytes. These occurrences range across shelf facies; thus A. missouriense is probably the most eurytopic of the skeletal algae. Codiacean chlorophyte phylloid algae are characteristically associated with shelf buildups and inner shelf/late highstand shoal grainstones. Fragments of dasycladacean chlorophytes are often associated with the shoal facies codiaceans. These algae appear rather stenotopic, requiring well-lit conditions. Potential porosity development involves dissolution of metastable algal blades and marine cements in buildup and grainstone facies.

Holterhoff, P.F. (Univ. of Cincinnati, OH (United States))

1991-03-01

425

Development of a Ground-based Experimental Facility for Space Micro-algae Photo-Bioreactor  

NASA Astrophysics Data System (ADS)

To develop a ground-based experimental facility for space micro-algal photo-bioreactor which produce algae and oxygen for astronaut and reduce carbon dioxide in closed-ecology life support system meanwhile Method Based on technical parameters and performance requirements project planning design drawing fabrication and debug were conducted Finally an experimental test for producing algae was done Its productivity for micro-algae was evaluated Result The facility worked well and the parameters such as energy consumption volume and productivity for algae met the design requirement The experimental test results demonstrated that the density of algae in the photo-bioreactor increased from 0 174 g DW cdot L -1 to 4 064 g DW cdot L -1 after 7 days growing Its productivity for the micro-algae was up to 11 1 g DW cdot d -1 The bioreactor of providing CO 2 for algae and taking O 2 from the culture medium adopt a new technique this is membrane The principle of it was suitable for the demand of space conditions Conclusion The facility has reasonable technical indices and smooth and dependable performances Its major working principle is fit for the demand of space micro-gravity conditions

Ai, W.; Guo, S.; Tang, Y.; Qin, L.; Deng, Y.

426

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

2009-05-01

427

Can benthic algae mediate larval behavior and settlement of the coral Acropora muricata?  

NASA Astrophysics Data System (ADS)

The resilience of coral reefs relies significantly on the ability of corals to recover successfully in algal-dominated environments. Larval settlement is a critical but highly vulnerable stage in the early life history of corals. In this study, we analyzed how the presence of two upright fleshy algae, Sargassum mcclurei (SM) and Padina australis (PA), and one crustose coralline algae, Mesophyllum simulans (MS), affects the settlement of Acropora muricata larvae. Coral larvae were exposed to seawater flowing over these algae at two concentrations. Larval settlement and mortality were assessed daily through four variables related to their behavior: swimming, substratum testing, metamorphosis, and stresses. Temperature, dissolved oxygen, pH, algal growth, and photosynthetic efficiency were monitored throughout the experiment. Results showed that A. muricata larvae can settle successfully in the absence of external stimuli (63 6 % of the larvae settled in control treatments). While algae such as MS may stimulate substrate testing and settlement of larvae in the first day after competency, they ultimately had a lower settlement rate than controls. Fleshy algae such as PA, and in a lesser measure SM, induced more metamorphosis than controls and seemed to eventually stimulate settlement. A diverse combination of signals and/or modifications of microenvironments by algae and their associated microbial communities may explain the pattern observed in coral settlement. Overall, this study contributes significantly to the knowledge of the interaction between coral and algae, which is critical for the resilience of the reefs.

Denis, V.; Loubeyres, M.; Doo, S. S.; de Palmas, S.; Keshavmurthy, S.; Hsieh, H. J.; Chen, C. A.

2014-06-01

428

Production and release of selenocyanate by different green freshwater algae in environmental and laboratory samples.  

PubMed

In a previous study, selenocyanate was tentatively identified as a biotransformation product when green algae were exposed to environmentally relevant concentrations of selenate. In this follow-up study, we confirm conclusively the presence of selenocyanate in Chlorella vulgaris culture medium by electrospray mass spectrometry, based on selenium's known isotopic pattern. We also demonstrate that the observed phenomenon extends to other green algae (Chlorella kesslerii and Scenedesmus obliquus) and at least one species of blue-green algae (Synechococcus leopoliensis). Further laboratory experiments show that selenocyanate production by algae is enhanced by addition of nitrate, which appears to serve as a source of cyanide produced in the algae. Ultimately, this biotransformation process was confirmed in field experiments where trace amounts of selenocyanate (0.215 0.010 ppb) were observed in a eutrophic, selenium-impacted river with massive algal blooms, which consisted of filamentous green algae (Cladophora genus) and blue-green algae (Anabaena genus). Selenocyanate abundance was low despite elevated selenium concentrations, apparently due to suppression of selenate uptake by sulfate, and insufficient nitrogen concentrations. Finally, trace levels of several other unidentified selenium-containing compounds were observed in these river water samples; preliminary suggestions for their identities include thioselenate and small organic Se species. PMID:22455319

LeBlanc, Kelly L; Smith, Matthew S; Wallschl輍er, Dirk

2012-06-01

429

[Epiphase carotenoids of the blue-green alga Anabaena variabilia].  

PubMed

Epiphase carotenoids were studied in the cells of the obligate phototrophous blue-green alga Anabaena variabilis. Ten pigment zones were detected by column chromatography on alumina and by TLC on cellulose and Silufol UV-254 plates. TLC in the B layer and paper chromatography did not reveal all pigment zones obtained on a column. The data of TLC on cellulose and on Silufol plates confirmed the purity and individual character of the fractions obtained on a column. These data showed also that the pigments obtained upon the separation of the extract on a column were not the products of its interaction with an active adsorbent. Absorption spectra of the isolated pigments were determined in various solvents, and speculations were made concerning the structure of the carotenoids. PMID:408584

Pakhlavuni, I K; Vasil'eva, V E; Gusev, M V

1977-01-01

430

A new ketosteroid from red alga Acanthophora spicifera  

NASA Astrophysics Data System (ADS)

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 against the human cancer cell lines, HCT-8, Bel-7402, BGC-823, A549 and HELA. Compounds 1, 2, 3 and 5 showed moderate cytotoxic activity against human cancer cell lines.

Shi, Dayong; Guo, Shuju; Fan, Xiao

2011-05-01

431

Antiviral activity of the red marine alga Ceramium rubrum.  

PubMed

An extract from the red marine alga Ceramium rubrum (Huds.) Ag. from the Bulgarian Black Sea seacoast considerably inhibited the reproduction of influenza viruses type A and B in vitro and in ovo. The virus-induced cytopathogenic effect (CPE), infectious virus yields and the production of hemagglutinin were all reduced at non-toxic concentrations of the extract. The virus-inhibitory effect was selective, dose-related and strain-specific; selectivity indices ranged 9.5-68.3. The inhibition affected adsorption as well as the intracellular stages of viral replication. The extract inhibited also the reproduction of herpes simplex virus (HSV) type 1 and type 2 in cell cultures. The preparation exhibited a strong HSV-inactivating activity. PMID:15287074

Serkedjieva, Julia

2004-06-01

432

Simultaneous coupling of phototaxis and electrotaxis in Volvox algae  

NASA Astrophysics Data System (ADS)

In nature, living creatures are affected by several stimuli simultaneously. The response of living creatures to stimuli is called taxis. In order to reveal the principles of taxis behavior in response to complex stimuli, we simultaneously applied photostimulation and electric stimulation perpendicularly to a Volvox algae solution. The probability distribution of the swimming direction showed that a large population of swimming cells moved in a direction that was the result of the composition of phototaxis and electrotaxis. More surprisingly, we uncovered the coupling of signs of taxis, i.e., coupling of phototaxis and electrotaxis induced positive electrotaxis, which did not emerge in the single stimulation experiments. We qualitatively explained the coupling of taxis based on the polarization of the swimming cells induced by the simultaneous photo- and electric stimulation.

Hayashi, Yoshikatsu; Sugawara, Ken

2014-04-01

433

QSAR for organic chemical bioconcentration in Daphnia, algae, and mussels.  

PubMed

Prediction of the bioconcentration of organic chemicals from water by aquatic organisms has important applications in the management of hazardous chemicals. This study gives a compilation of bioconcentration factors on a wet weight basis (BCFw) of 52 organic chemicals by Daphnia magna from aqueous solution. The bioconcentration factors for the chemicals in Daphnia were successfully correlated with their n-octanol/water partition coefficients (log Kow) using a linear regression analysis. In addition to the ordinary least-square regression technique, the geometric mean regression technique is also used because this takes into account deviations in Kow values. Both results show that the Kow value of a chemical is a good predictor of the BCF in Daphnia. The BCF-Kow relationships between Daphnia, algae (Chlorella), and mussels (Mytilus edulis) are compared with each other. PMID:1815359

Geyer, H J; Scheunert, I; Brggemann, R; Steinberg, C; Korte, F; Kettrup, A

1991-12-01

434

Antithrombotic effects of bromophenol, an alga-derived thrombin inhibitor  

NASA Astrophysics Data System (ADS)

Thrombin, the ultimate proteinase of the coagulation cascade, is an attractive target for the treatment of a variety of cardiovascular diseases. A bromophenol derivative named (+)-3-(2,3-dibromo-4, 5-dihydroxy-phenyl)-4-bromo-5,6-dihydroxy-1,3-dihydroiso-benzofuran 1, isolated from the brown alga Leathesia nana exhibited significant thrombin inhibitory activity. In this study, we investigated the inhibition of human thrombin in vitro with this bromophenol derivative, and its antithrombotic efficacy in vivo using the arteriovenous shunt model and the ferric chloride-induced arterial thrombosis model in rats. The results show that the bromophenol derivative is a potential inhibitor of thrombin (IC50=1.03 nmol/L). In antithrombotic experiments in vivo, the bromophenol derivative also shows good effect comparing with the control group. These data indicate that the bromophenol derivative is a potential drug for prophylaxis and the treatment of thrombotic diseases.

Shi, Dayong; Li, Xiaohong; Li, Jing; Guo, Shuju; Su, Hua; Fan, Xiao

2010-01-01

435

Degradation of Petroleum by an Alga, Prototheca Zopfii  

PubMed Central

Prototheca zopfii is an achlorophyllous alga which degrades oil. It has been found to degrade 10 and 40% of a motor oil and crude oil, respectively, when tested under appropriate conditions. Degradation of the crude oil observed in this study compares well with the amount of degradation accomplished by bacteria. P. zopfii was found to degrade a greater percentage of the aromatic hydrocarbons in motor oil than of the saturated hydrocarbons and a greater percentage of saturated hydrocarbons in crude oil than of aromatic hydrocarbons. Resins and asphaltenes were produced during degradation of motor oil, whereas these fractions in crude oil were degraded. P. zopfii did not demonstrate preferential utilization of lower homologues of cycloalkanes and aromatics as has been observed with bacteria.

Walker, J. D.; Colwell, R. R.; Petrakis, L.

1975-01-01

436

Photosynthetic Activities of the Halophilic Alga Dunaliella parva  

PubMed Central

Dunaliella parva, a unicellular halophilic alga, was found to evolve oxygen photosynthetically only in the presence of a high osmolar concentration. Cell free preparations were obtained by placing the cells in a medium of low osmolarity. The fragments obtained showed a high photoreducing and photophosphorylating activity except for their inability to catalyze all ferredoxin dependent photoreactions. Placing the cells in a medium of intermediate osmolarity produced a chloroplast preparation which maintained some capacity for O2 evolution and CO2 fixation, while possessing the ability to catalyze the photoinduced reduction of ferricyanide. Enzymic and photosynthetic reactions of cell-free preparations from D. parva were inhibited, rather than stimulated, by the salt concentration optimal for growth. These results were interpreted as indicating the existence of a steep NaCl gradient in vivo between the medium and the cell compartments which are not permeable to salt.

Ben-Amotz, Ami; Avron, Mordhay

1972-01-01

437

Hydrogen production by the green alga Scenedesmus acutus  

SciTech Connect

H production by Scenedesmus acutus was studied, with special attention to the suitability of Na2S2O4 as an O-binding compound and the effect of light intensity and initial H pressure. Na2S2O4 is an efficient O binder. However, Na2S2O4 concentrations are more than 12 mM proved to be toxic to the algae. With an optimum light intensity of 2 klx, the H production stopped at a maximum H concentration of 5% in the gaseous phase. When the gaseous phase over the culture was replaced by N periodically, H production continued for more than 9 weeks in a medium which only consisted of a phosphate buffer.

Ten Hoopen, H.J.G.; Snellink, L.J.; Van Gemert, J.M.; Fuchs, A.; Roels, J.A.

1984-01-01

438

Grazing-activated chemical defence in a unicellular marine alga  

NASA Astrophysics Data System (ADS)

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 lyase. Such a mechanism is similar to macrophyte defence reactions,. Here we show that this reaction deters protozoan herbivores, presumably through the production of highly concentrated acrylate, which has antimicrobial activity. Protozoan predators differ in their ability to ingest and survive on prey with high-activity DMSP lyase, but all grazers preferentially select strains with low enzyme activity when offered prey mixtures. This defence system involves investment in a chemical precursor, DMSP, which is not self-toxic and has other useful metabolic functions. We believe this is the first report of grazing-activated chemical defence in unicellular microorganisms.

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

1997-06-01

439

Alternate-Fueled Flight: Halophytes, Algae, Bio-, and Synthetic Fuels  

NASA Technical Reports Server (NTRS)

Synthetic and biomass fueling are now considered to be near-term aviation alternate fueling. The major impediment is a secure sustainable supply of these fuels at reasonable cost. However, biomass fueling raises major concerns related to uses of common food crops and grasses (some also called "weeds") for processing into aviation fuels. These issues are addressed, and then halophytes and algae are shown to be better suited as sources of aerospace fuels and transportation fueling in general. Some of the history related to alternate fuels use is provided as a guideline for current and planned alternate fuels testing (ground and flight) with emphasis on biofuel blends. It is also noted that lessons learned from terrestrial fueling are applicable to space missions. These materials represent an update and additions to the Workshop on Alternate Fueling Sustainable Supply and Halophyte Summit at Twinsburg, OH, Oct. 17 to 18, 2007 (ref. 1).

Hendricks, R. C.

2007-01-01

440

Alternate-Fueled Flight: Halophytes, Algae, Bio-, and Synthetic Fuels  

NASA Technical Reports Server (NTRS)

Synthetic and biomass fueling are now considered to be near-term aviation alternate fueling. The major impediment is a secure sustainable supply of these fuels at reasonable cost. However, biomass fueling raises major concerns related to uses of common food crops and grasses (some also called "weeds") for processing into aviation fuels. These issues are addressed, and then halophytes and algae are shown to be better suited as sources of aerospace fuels and transportation fueling in general. Some of the history related to alternate fuels use is provided as a guideline for current and planned alternate fuels testing (ground and flight) with emphasis on biofuel blends. It is also noted that lessons learned from terrestrial fueling are applicable to space missions. These materials represent an update (to 2009) and additions to the Workshop on Alternate Fueling Sustainable Supply and Halophyte Summit at Twinsburg, Ohio, October 17 to 18, 2007.

Hendricks, R. C.

2012-01-01

441

Testing an Algae-Based Air-Regeneration System  

NASA Technical Reports Server (NTRS)

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 for up to 365 days. Under standard conditions (50-66 micro mol/sq mm s (PPF), 450 micro mol mol of CO2), mature tubes can remove CO2 at a rate of up to 90 micro mol/sq m min. Under these conditions, approximately 200 square meters of area would be required for each member of the crew. However, the rate of uptake increases with both photon flux and CO2 concentration in accordance with Michaelis-Menton dynamics. An extrapolation to conditions of saturating light and carbon dioxide indicates that the area required can be reduced by a factor of at least 2.5.

Nienow, James

1998-01-01

442

Enhanced Genetic Tools for Engineering Multigene Traits into Green Algae  

PubMed Central

Transgenic microalgae have the potential to impact many diverse biotechnological industries including energy, human and animal nutrition, pharmaceuticals, health and beauty, and specialty chemicals. However, major obstacles to sophisticated genetic and metabolic engineering in algae have been the lack of well-characterized transformation vectors to direct engineered gene products to specific subcellular locations, and the inability to robustly express multiple nuclear-encoded transgenes within a single cell. Here we validate a set of genetic tools that enable protein targeting to distinct subcellular locations, and present two complementary methods for multigene engineering in the eukaryotic green microalga Chlamydomonas reinhardtii. The tools described here will enable advanced metabolic and genetic engineering to promote microalgae biotechnology and product commercialization.

Rasala, Beth A.; Chao, Syh-Shiuan; Pier, Matthew; Barrera, Daniel J.; Mayfield, Stephen P.

2014-01-01

443

The effect of low temperature on Antarctic endolithic green algae  

NASA Technical Reports Server (NTRS)

Laboratory experiments show that undercooling to about -5 degrees C occurs in colonized Beacon sandstones of the Ross Desert, Antarctica. High-frequency temperature oscillations between 5 degrees C and -5 degrees C or -10 degrees C (which occur in nature on the rock surface) did not damage Hemichloris antarctica. In a cryomicroscope, H. antarctica appeared to be undamaged after slow or rapid cooling to -50 degrees C. 14CO2 incorporation after freezing to -20 degrees C was unaffected in H. antarctica or in Trebouxia sp. but slightly depressed in Stichococcus sp. (isolated from a less extreme Antarctic habitat). These results suggest that the freezing regime in the Antarctic desert is not injurious to endolithic algae. It is likely that the freezing-point depression inside the rock makes available liquid water for metabolic activity at subzero temperatures. Freezing may occur more frequently on the rock surface and contribute to the abiotic nature of the surface.

Meyer, M. A.; Morris, G. J.; Friedmann, E. I.

1988-01-01

444

The cellulose synthase superfamily in fully sequenced plants and algae  

PubMed Central

Background The cellulose synthase superfamily has been classified into nine cellulose synthase-like (Csl) families and one cellulose synthase (CesA) family. The Csl families have been proposed to be involved in the synthesis of the backbones of hemicelluloses of plant cell walls. With 17 plant and algal genomes fully sequenced, we sought to conduct a genome-wide and systematic investigation of this superfamily through in-depth phylogenetic analyses. Results A single-copy gene is found in the six chlorophyte green algae, which is most closely related to the CslA and CslC families that are present in the seven land plants investigated in our analyses. Six proteins from poplar, grape and sorghum form a distinct family (CslJ), providing further support for the conclusions from two recent studies. CslB/E/G/H/J families have evolved significantly more rapidly than their widely distributed relatives, and tend to have intragenomic duplications, in particular in the grape genome. Conclusion Our data suggest that the CslA and CslC families originated through an ancient gene duplication event in land plants. We speculate that the single-copy Csl gene in green algae may encode a mannan synthase. We confirm that the rest of the Csl families have a different evolutionary origin than CslA and CslC, and have proposed a model for the divergence order among them. Our study provides new insights about the evolution of this important gene family in plants.

2009-01-01

445

Structurally reduced monosaccharide transporters in an evolutionarily conserved red alga.  

PubMed

The unicellular red alga Galdieria sulphuraria is a facultative heterotrophic member of the Cyanidiaceae, a group of evolutionary highly conserved extremophilic red algae. Uptake of various sugars and polyols is accomplished by a large number of distinct plasma membrane transporters. We have cloned three transporters [GsSPT1 (G. sulphuraria sugar and polyol transporter 1), GsSPT2 and GsSPT4], followed their transcriptional regulation and assayed their transport capacities in the heterologous yeast system. SPT1 is a conserved type of sugar/H(+) symporter with 12 predicted transmembrane-spanning domains, whereas SPT2 and SPT4 represent monosaccharide transporters, characterized by only nine hydrophobic domains. Surprisingly, all three proteins are functional plasma membrane transporters, as demonstrated by genetic complementation of a sugar uptake-deficient yeast mutant. Substrate specificities were broad and largely redundant, except for glucose, which was only taken up by SPT1. Comparison of SPT1 and truncated SPT1(Delta1-3) indicated that the N-terminus of the protein is not required for sugar transport or substrate recognition. However, its deletion affected substrate affinity as well as maximal transport velocity and released the pH dependency of sugar uptake. In line with these results, uptake by SPT2 and SPT4 was active but not pH-dependent, making a H(+) symport mechanism unlikely for the truncated proteins. We postulate SPT2 and SPT4 as functional plasma membrane transporters in G. sulphuraria. Most likely, they originated from genes encoding active monosaccharide/H(+) symporters with 12 transmembrane-spanning domains. PMID:17497961

Schilling, Silke; Oesterhelt, Christine

2007-09-01

446

Comparing the Effects of Symbiotic Algae (Symbiodinium) Clades C1 and D on Early Growth Stages of Acropora tenuis  

PubMed Central

Reef-building corals switch endosymbiotic algae of the genus Symbiodinium during their early growth stages and during bleaching events. Clade C Symbiodinium algae are dominant in corals, although other clades including A and D have also been commonly detected in juvenile Acroporid corals. Previous studies have been reported that only molecular data of Symbiodinium clade were identified within field corals. In this study, we inoculated aposymbiotic juvenile polyps with cultures of clades C1 and D Symbiodinium algae, and investigated the different effect of these two clades of Symbiodinium on juvenile polyps. Our results showed that clade C1 algae did not grow, while clade D algae grew rapidly during the first 2 months after inoculation. Polyps associated with clade C1 algae exhibited bright green fluorescence across the body and tentacles after inoculation. The growth rate of polyp skeletons was lower in polyps associated with clade C1 algae than those associated with clade D algae. On the other hand, antioxidant activity (catalase) of corals was not significantly different between corals with clade C1 and clade D algae. Our results suggested that clade D Symbiodinium algae easily form symbiotic relationships with corals and that these algae could contribute to coral growth in early symbiosis stages.

Yuyama, Ikuko; Higuchi, Tomihiko

2014-01-01

447

Comparing the Effects of Symbiotic Algae (Symbiodinium) Clades C1 and D on Early Growth Stages of Acropora tenuis.  

PubMed

Reef-building corals switch endosymbiotic algae of the genus Symbiodinium during their early growth stages and during bleaching events. Clade C Symbiodinium algae are dominant in corals, although other clades - including A and D - have also been commonly detected in juvenile Acroporid corals. Previous studies have been reported that only molecular data of Symbiodinium clade were identified within field corals. In this study, we inoculated aposymbiotic juvenile polyps with cultures of clades C1 and D Symbiodinium algae, and investigated the different effect of these two clades of Symbiodinium on juvenile polyps. Our results showed that clade C1 algae did not grow, while clade D algae grew rapidly during the first 2 months after inoculation. Polyps associated with clade C1 algae exhibited bright green fluorescence across the body and tentacles after inoculation. The growth rate of polyp skeletons was lower in polyps associated with clade C1 algae than those associated with clade D algae. On the other hand, antioxidant activity (catalase) of corals was not significantly different between corals with clade C1 and clade D algae. Our results suggested that clade D Symbiodinium algae easily form symbiotic relationships with corals and that these algae could contribute to coral growth in early symbiosis stages. PMID:24914677

Yuyama, Ikuko; Higuchi, Tomihiko

2014-01-01

448

Effects of extreme seasonality on community structure and functional group dynamics of coral reef algae in the southern Red Sea (Eritrea)  

Microsoft Academic Search

Spatial and temporal variation in the biomass of four functional groups of coral reef algae (canopy algae, foliose algae, turf algae and crustose corallines) was investigated in the southern Red Sea. This region is characterised by extremely high summer temperatures (ca. 35蚓). Strong seasonal shifts in the relative contribution of each group to the total macroalgal biomass were observed. On

M. Ateweberhan; J. H. Bruggemann; A. M. Breeman

2006-01-01

449

Biotransformation of mercury in pH-stat cultures of eukaryotic freshwater algae  

Microsoft Academic Search

Eukaryotic algae were studied to determine their ability to biotransform HgII under aerated and pH controlled conditions. All algae converted HgII into ?-HgS and Hg0 to varying degrees. When HgII was administered as HgCl2 to the algae, biotransformation by species of Chlorophyceae (Selenastrum\\u000a minutum and Chlorella fusca var. fusca) was initiated with ?-HgS synthesis (K\\u000a 1\\/2 of hours) and concomitant

David J. A. Kelly; Kenneth Budd; Daniel D. Lefebvre

2007-01-01

450

Compsopogon cf. coeruleus, a benthic red alga (Rhodophyta) new to the Laurentian Great Lakes  

USGS Publications Warehouse

We found Compsopogon cf. coeruleus for the first time in the Laurentian Great Lakes, growing on limestone rocks at a depth of 21 m on Six Fathom Bank in central Lake Huron. It is the first freshwater red alga to be found in the Great Lakes and the only red alga ever found on an offshore reef in the Great Lakes. However, because this alga usually inhabits water 10-28A?C and has not survived freezing winter temperatures elsewhere, it may not be a permanent member of the flora.

Manny, Bruce A.; Edsall, Thomas A.; Wujek, Daniel E.

1991-01-01

451

Aquaculture: Algae. (Latest citations from the Life Sciences collection database). Published Search  

SciTech Connect

The bibliography contains citations concerning the commercial cultivation of algae as a facet of aquaculture. Topics include descriptions and characteristics of algal species, environmental variables affecting productivity, nutritional aspects, infestation and disease, genetic manipulation, and production technology. End product applications examine algae as biomass for energy production, food source for humans, animal feed source, and a source for chemical by-products such as chlorophylls. Harvesting of algae as a source of single-celled protein is referenced in a related bibliography. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

NONE

1996-04-01

452

Aquaculture: Algae. (Latest citations from the Life Sciences Collection data base). Published Search  

SciTech Connect

The bibliography contains citations concerning the commercial cultivation of algae as a facet of aquaculture. Topics include descriptions and characteristics of algal species, environmental variables affecting productivity, nutritional aspects, infestation and disease, genetic manipulation, and production technology. End product applications examine algae as biomass for energy production, food source for humans, animal feed source, and a source for chemical by-products such as chlorophylls. Harvesting of algae as a source of single-celled protein is referenced in a related bibliography. (Contains a minimum of 171 citations and includes a subject term index and title list.)

Not Available

1992-05-01

453

Laser-induced breakdown spectroscopy for quantitative analysis of copper in algae  

NASA Astrophysics Data System (ADS)

Laser-induced breakdown spectroscopy (LIBS) has been applied for quantitative analysis of Cu in algae plants, an issue of paramount importance for environmental monitoring. For the analysis with LIBS, algae were compacted into solid pellets with powdered calcium hydroxide addition as binder and a pulsed Nd:YAG laser was employed to produce the plasmas in air at atmospheric pressure. In this approach, atomic lines from traces of Cu were detected, as well as other major and minor elements. The plasma was characterized and a calibration curve was constructed with reference samples prepared with calcium hydroxide. The results obtained demonstrated the usefulness of the method for Cu monitoring in algae plants.

Garcimu隳, M.; D燰z Pace, D. M.; Bertuccelli, G.

2013-04-01

454

Vascular Steal Syndrome and Shewanella alga Infection Requiring Amputation in a Hemodialysis Patient.  

PubMed

Shewanella alga is a rare gram-negative marine bacterium. Its role as a pathogenic organism is gradually evolving with sporadic cases being reported in humans. We report a case of vascular steal syndrome secondary to a polytetrafluoroethylene (PTFE) graft in the upper extremity of an end-stage renal disease (ESRD) patient on maintenance hemodialysis, which was complicated by infection with S. alga. This resulted in extensive myonecrosis requiring amputation of the limb. To our knowledge this is the fourth case of primary S. alga infection, and the first case in a hemodialysis patient reported in the medical literature from the United States. We also discuss the biochemical tests for identification and differentiation of S. alga from a closely related strain S. putrefaciens. PMID:17657124

Jammula, Praveen; Gupta, Rajiv; Agraharkar, Mahendra

2003-01-01

455

Effect of O3 and O3/H2O2 on algae harvesting using chitosan.  

PubMed

We examined the effects of pre-oxidation using ozone (O3) and a combination of O3 and hydrogen peroxide (O3/H2O2) on algae suspensions and their harvesting. Inactivation of algae cells, release of intracellular organic matter (IOM), mineralization of extracellular organic matter (EOM), and changes in molecular weight distribution of EOM were found after pre-oxidation. Enhanced separation efficiency of turbidity, dissolved organic carbon (DOC), protein, and polysaccharide using chitosan and polyaluminum chloride (PACl) was found after pre-oxidation, especially when algae cells were subject to O3/H2O2. Chitosan showed higher efficiency than PACl. Judging from the remarkable increase in floc size, it was proposed that released IOM formed complexes with cationic chitosan and resulted in enhanced dual flocculation and facilitated algae separation. PMID:23508154

Pranowo, R; Lee, D J; Liu, J C; Chang, J S

2013-01-01

456

Catalytic Hydrothermal Gasification of Lignin-Rich Biorefinery Residues and Algae.  

National Technical Information Service (NTIS)

This report describes the results of the work performed by PNNL using feedstock materials provided by the National Renewable Energy Laboratory, KL Energy and Lignol lignocellulosic ethanol pilot plants. Test results with algae feedstocks provided by Genif...

A. H. Zacher C. Valkenburg D. C. Elliott D. M. Santosa G. G. Neuenschwander L. J. Rotness S. A. Tjokro-Rahardjo S. B. Jones T. R. Hart

2009-01-01

457

Assessment of Blue-Green Algae in Substantially Reducing Nitrogen Fertilizer Requirements for Biomass Fuel Crops.  

National Technical Information Service (NTIS)

Laboratory, mass culture, and field studies are being undertaken in order to assess the potential of using blue-green algae (cyanobacteria) as nitrogen biofertilizers on irrigated ground. Of seven candidate strains, two were chosen for application to repl...

D. B. Anderson P. M. Molten B. Metting

1981-01-01

458

Cultivation of Macroscopic Marine Algae and Freshwater Aquatic Weeds. Progress Report, May 1--December 31, 1976.  

National Technical Information Service (NTIS)

Research was divided between basic physiological studies of the growth and nutrient-uptake kinetics of macroscopic marine algae and the more applied problems involved in the selection of species and the development of inexpensive, non-energy intensive cul...

J. H. Ryther

1977-01-01

459

Algae for Controlled Ecological Life Support System Diet Characterization of Cyanobacteria 'Spirulina' in Batch Cultures.  

National Technical Information Service (NTIS)

Spirulina sp. is a bioregenerative photosynthetic and edible alga for space craft crews in a Closed Ecological Life Support System (CLESS). It was characterized for growth rate and biomass yield in batch cultures, under various environmental conditions. T...

M. G. Tadros

1990-01-01

460

Evidence for a photoprotective function for secondary carotenoids of snow algae  

SciTech Connect

Snow algae occupy a unique habitat in high altitude and polar environments. These algae are often subject to extremes in nutrient availability, acidity, solar irradiance, desiccation, and ambient temperature. This report documents the accumulation of secondary carotenoids by snow algae in response to the availability of nitrogenous nutrients. Unusually large accumulations of astaxanthin esters in extra-chloroplastic lipid globules produce the characteristic red pigmentation typical of some snow algae (e.g., Chlamydomonas nivalis (Bauer) Wille). Consequently, these compounds greatly reduce the amount of light available for absorption by the light-harvesting pigment-protein complexes, thus potentially limiting photoinhibition and photodamage caused by intense solar radiation. The esterification of astaxanthin with fatty acids represents a possible mechanism by which this chromophore can be concentrated within cytoplasmic globules to maximize its photoprotective efficiency. 53 refs., 2 figs., 4 tabs.

Bidigare, R.R.; Ondrusek, M.E. (Univ. of Hawaii, Honolulu, HI (United States)); Kennicutt, M.C. II (Geochemical Environmental Research Group, College Station, TX (United States)); Iturriaga, R. (Univ. of Southern California, Los Angeles, CA (United States)); Harvey, H.R. (Univ. of Maryland, Solomons, MD (United States)); Hoham, R.W. (Colgate Univ., Hamilton, NY (United States)); Macko, S.A. (Univ. of Virginia, Charlottesville, VA (United States))

1993-08-01

461

Laboratory Culture of Zebra ('Dreissena polymorpha') and Quagga ('D. bugensis') Mussel Larvae Using Estuarine Algae.  

National Technical Information Service (NTIS)

This paper details procedures for rearing zebra and quagga mussel larve through and beyond metamorphosis on diets of estuarine algae, Isochrysis galbana T-ISO and Pavola (=Monochrysis) lutheri. Saturated fatty acids predominated in I. galbana and P. Luthe...

D. A. Wright E. M. Setzler-Hamilton J. A. Magee H. R. Harvey

1996-01-01

462

Preliminary observations on the benthic marine algae of the Gorringe seabank (northeast Atlantic Ocean)  

NASA Astrophysics Data System (ADS)

Examination of marine samples collected in 2006 from the Gettysburg and Ormonde seamounts on the Gorringe seabank southwest of Portugal has revealed 29 benthic Chlorophyta, Phaeophyceae (Ochrophyta), and Rhodophyta that were identified provisionally to genus and to species. Combining lists for the present and a previous expedition brings the total of algae thus far recorded to 48. The brown alga Zonaria tournefourtii and the red alga Cryptopleura ramosa were the most abundant species in the present collections. The kelp Laminaria ochroleuca was present only in the Gettysburg samples while Saccorhiza polyschides was observed only on the Ormonde seamount. Comparisons with the benthic marine algae recorded on seamounts in the mid-Atlantic Azores archipelago show features in common, notably kelp forests of L. ochroleuca at depths below 30 m and Z. tournefortii dominance in shallower waters.

Tittley, Ian; da Silva Vaz 翼varo, Nuno Miguel; de Melo Azevedo Neto, Ana Isabel

2014-06-01

463

LIPID BIOMARKER CHARACTERIZATION OF BLOOM-RELATED DINOFLAGELLATES AND OTHER EUKARYOTIC ALGAE  

EPA Science Inventory

Marine eukaryotic algae synthesize an array of lipids of chemotaxonomic utility that are potentially valuable in characterizing phytoplankton communities. Sterols and photopigments characteristic of dinoflagellates are rarely found in other algal classes. Long chain (C28) highly ...

464

EVALUATION OF FILTER FEEDING FISHES FOR REMOVING EXCESSIVE NUTRIENTS AND ALGAE FROM WASTEWATER  

EPA Science Inventory

The feasibility of utilizing finfish for the removal and recycling of excessive nutrients and algae from wastewater was investigated. The silver carp (Hypopthalmichthyes molitrix) and the bighead carp (Aristichthyes nobilis) were chosen due to their specifically adapted filter fe...

465

Chromium toxicity on two linked trophic levels. I. Effects of contaminated algae on Daphnia magna.  

PubMed

The effects of feeding Daphnia magna on algae (Scenedesmus acutus) pretreated with different concentrations of Cr(VI) were studied. A positive effect on growth and newborn production rate was observed in the daphnids fed on algae exposed to 1 mg/liter Cr(VI). Fecundity and growth were drastically reduced in daphnids fed on algae exposed to 10 mg/liter Cr(VI). Since the algae, cultured in the presence of these two Cr(VI) concentrations, supplied daphnids with similar amounts of chromium, the observed effects on the population dynamics of D. magna were attributed more to alterations of the nutritional value of the algal food, due to the Cr treatment, than to a toxic effect of the metal. PMID:7682919

Gorbi, G; Corradi, M G

1993-02-01

466

Aluminum bioavailability to the green alga Chlorella pyrenoidosa in acidified synthetic soft water  

SciTech Connect

A unicellular green alga, Chlorella pyrenoidosa, was exposed to inorganic Al under controlled experimental conditions to determine whether the biological response elicited by the dissolved metal could be predicted from the free-metal ion concentration, [Al[sup 3+

Parent, L.; Campbell, P.G.C. (Univ. du Quebec, Ste-Foy (Canada))

1994-04-01

467

Viral infection of the symbiotic chlorella-like alga present in Hydra viridis.  

PubMed

Attempts to culture the Chlorella-like green alga found in a symbiotic association with the Florida strain of a green hydra, Hydra viridis, have been unsuccessful. Ultrastructural studies of the algae isolated from the host revealed that large (185 nm in diameter) viral particles appeared in the nuclear region of the algae 2 to 6 hr after their isolation from the hydra. By 12-20 hr, the entire population of algae was lysed. The source of the virus is unknown since it has not been detected in thin sections of intact hydra or in algal cells immediately after their isolation. The virus attached to the algal cell wall in a manner reminiscent of many bacteriophage infections. Attempts to infect three other culture-grown Chlorella strains with crude lysates or purified viral particles have been unsuccessful. PMID:18635088

Meints, R H; Van Etten, J L; Kuczmarski, D; Lee, K; Ang, B

1981-09-01

468

CONTRIBUTION OF MARINE ALGAE TO TRIHALOMETHANE PRODUCTION IN CHLORINATED ESTUARINE WATER  

EPA Science Inventory

Three species of marine algae representing major taxonomic groups of phytoplankton, Isochrysis galbana (Chrysophyceae), Carteria sp. (Chlorophyceae), and Thalassiosira pseudonana (Bacillariphyceae), were utilized to investigate the potential of natural occurring chlorophyll a of ...

469

Wind, Currents and Dormant Algae Cysts May Have Created "Perfect" Red-Tide Conditions  

NSF Publications Database

... Physics Press Release 05-094Wind, Currents and Dormant Algae Cysts May Have Created "Perfect ... other occasions. This time, unusual winds and currents brought it directly into the bay." Anderson ...

470

The concentration of radium, thorium, and uranium by tropical marine algae  

Microsoft Academic Search

Twenty species of marine algae were collected between 1961 and 1968 from coastal waters of Puerto Rico and analyzed chemically for total organic material, protein nitrogen, and calcium, and radiochemically for the naturally occurring alpha particle emitters 228Ra, \\

DAVID N. EDGINGTON; SOLON A. GORDON; MICHAEL M. THOMMES; LUIS R. ALMODOVAR

1970-01-01

471

Benchmark study on algae harvesting with backwashable submerged flat panel membranes.  

PubMed

The feasibility of algae harvesting with submerged flat panel membranes was investigated as pre-concentration step prior to centrifugation. Polishing of the supernatant coming from the centrifuge was evaluated as well. The effect of membrane polymer (polyvinyl chloride [PVC], polyethersulfone polyvinyl-pyrollidone [PES-PVP], poly vinylidene fluoride [PVDF]), pore size (microfiltration [MF], ultrafiltration [UF]), algae cell concentrations and species were investigated at lab-scale. In addition, backwashing as fouling control was compared to standard relaxation. PVDF was the superior polymer, and UF showed better fouling resistance. Backwashing outperformed relaxation in fouling control. The backwashable membranes allowed up to 300% higher fluxes compared to commercial flat panel benchmark (PVC) membranes. Estimations on energy consumption for membrane filtration followed by centrifugation revealed relatively low values of 0.169 kW h/kg of dry weight of algae compared to 0.5 kW h/kg for algae harvesting via classical centrifuge alone. PMID:23274222

De Baerdemaeker, Tom; Lemmens, Bert; Dotremont, Chris; Fret, Jorien; Roef, Luc; Goiris, Koen; Diels, Ludo

2013-02-01

472

Life Cycle, Ecology, and Management Considerations of the Green Filamentous Alga, 'Pithophora'.  

National Technical Information Service (NTIS)

Pithophora, a green filamentous, spore-forming alga in the order Cladophorales, forms infestations of thick free-floating mats in small impoundments, shallow lakes, and coves and channels of larger lakes and reservoirs throughout the midwest and southeast...

C. A. Lembi N. L. Pearlmutter D. F. Spencer

1980-01-01

473

The Antimicrobial Properties of Red Algae. The Fight of Your Life: Battling Bacteria.  

ERIC Educational Resources Information Center

Describes a research project in which a professor and a student collaborated in the screening of macroscopic algae for antimicrobial properties. Includes background information, materials and methods, results, and a discussion of the experiment. (SAH)

Case, Christine L.; Warner, Michael

2001-01-01

474

Developing Molecular Genetic Tools to Facilitate Economic Production in Green Algae.  

National Technical Information Service (NTIS)

It is now accepted that algae have enormous potential to generate economically viable and environmentally sustainable liquid fuels that can help mitigate the effects of a diminishing supply of fossil fuel. The achievement of economic biofuel production fr...

D. R. Georgianna J. Gimpel M. J. Hannon S. P. Mayfield

2012-01-01

475

A cryptic intracellular green alga in Ginkgo biloba : ribosomal DNA markers reveal worldwide distribution  

Microsoft Academic Search

Intracellular symbioses involving eukaryotic microalgae and a variety of heterotrophic protists and invertebrates are widespread,\\u000a but are unknown in higher plants. Recently, we reported the isolation and molecular identification of a Coccomyxa-like green alga from in vitro cell cultures of Ginkgo biloba L. This alga resides intracellularly in an immature precursor form with a nonfunctional chloroplast, implying that algal\\u000a photosynthetic

Jocelyne Tr幦ouillaux-Guiller; Volker A. R. Huss

2007-01-01

476

Effect of selenium on the lipids of two unicellular marine algae  

SciTech Connect

The incorporation of selenium into the lipids of two unicellar marine algae has been investigated. Axenic cultures of the green algae Dunaliella primolecta and the red algae Porphyridium cruentum were grown in the presence of sublethal quantities of selenium (10 ppm) as selenite. Both algae were found to contain selenium bound to all purified lipids, except for saturated hydrocarbons. Of the lipids which contain selenium, carotenoid pigments show the greatest selenium concentration (..beta..-carotene: 1.3..mu..gSe/mg lipid; zeaxanthin: 1.1..mu..gSe/mg lipid) in both algae. P. cruentum contains about ten times as much lipid-associated selenium as D. primolecta, even though the lipids of both algae were very similar. This selenium has been shown to be incorporated non-metabolically into the lipid molecule. The lipid-associated selenium is probably non-covalently bound to the lipid molecule and may interact with double bonds. Selenite does not affect the lipid composition of D. primolecta, as compared with algae grown in the absence of added selenium. A selenium-induced 40% decrease in the cell content of eicosapentaenoic acid (20:5omega3) and 20% decrease in arachidonic acid (20:4omega6) in polar lipids (glycolipids plus phospholipids) was observed in P. cruentum. A 25% decrease in the chlorophyll a content of this red algae also occurred. The cell content of other fatty acids, phospholipids and glycolipids was unaltered by selenium. These results are consistent with a selenite-induced oxidation of P. cruentum lipids. Selenium is able to increase the antioxidant potential of algal cells. However, no in vivo selenium-induced protection of algal lipids from oxidation was apparent.

Gennity, J.M.

1983-01-01

477

Genetic analysis of the Photosystem I subunits from the red alga, Galdieria sulphuraria  

Microsoft Academic Search

Currently, there are very little data available regarding the photosynthetic apparatus of red algae. We have analyzed the genes for Photosystem I in the recently sequenced genome of the red alga Galdieria sulphuraria. All subunits that are conserved between plants and cyanobacteria were unambiguously identified in the Galdieria genome: PsaA, PsaB, PsaC, PsaD, PsaE, PsaF, PsaI, PsaJ, PsaK and PsaL.

Christopher Vanselow; Andreas P. M. Weber; Kirsten Krause; Petra Fromme

2009-01-01

478

Functional response of Oikopleura dioica to house clogging due to exposure to algae of different sizes  

Microsoft Academic Search

The functional response of the appendicularian Oikopleura dioica was investigated with a unialgal diet (Isochrysis galbana, 0-1,600 痢 C l-1) and with additions of specific concentrations of algae either smaller than the incurrent filter mesh size (Rhodomonas baltica, 90 痢 C l-1; Thalassiosira weissflogii, 60 痢 C l-1) or larger algae (Ceratium lineatum, 8 痢 C l-1; C. tripos, 52

P. Tiselius; J. Petersen; T. Nielsen; M. Maar; E. M鷲ler; S. Satapoomin; K. T霵nesson; T. Zervoudaki; E. Christou; A. Giannakourou; A. Sell; C. Vargas

2003-01-01

479

Quantum coherent propagation of complex molecules through the frustule of the alga Amphipleura pellucida  

NASA Astrophysics Data System (ADS)

Recent advances in the manipulation of molecules now allow us to also probe nanoporous silified biomaterials. We demonstrate the quantum coherent propagation of phthalocyanine through the skeleton of the alga Amphipleura pellucida. A micro-focused laser source prepares a molecular beam which is sufficiently delocalized to be coherently transmitted through the alga's frustulein spite of the substantial dispersive interaction between each molecule and the nanomembrane.

Sclafani, Michele; Juffmann, Thomas; Knobloch, Christian; Arndt, Markus

2013-08-01

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Light dependence of quantum yields for PSII charge separation and oxygen evolution in eucaryotic algae  

Microsoft Academic Search

Quantum yields of photosystem II (PSII) charge separation (Phi(P)) and oxygen production (Phi(O2)) were determined by simultaneous measurements of oxygen production and variable fluorescence in four different aquatic microalgae representing three different taxonomic groups: the freshwater alga Scenedesmus protuberans (Chlorophyceae) and the marine algae Phaeocystis globosa (Prymnesiophyceae), Emiliania huxleyi (Prymnesiophyceae), and Phaeodactylum tricornutum (Bacillariophyceae). In S. protuberans, P. tricornutum, and

Flameling A. I; Jacco Kromkamp

1998-01-01