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Sample records for include algae chara

  1. The distribution of cell wall polymers during antheridium development and spermatogenesis in the Charophycean green alga, Chara corallina.

    Science.gov (United States)

    Domozych, David S; Sørensen, Iben; Willats, William G T

    2009-11-01

    The production of multicellular gametangia in green plants represents an early evolutionary development that is found today in all land plants and advanced clades of the Charophycean green algae. The processing of cell walls is an integral part of this morphogenesis yet very little is known about cell wall dynamics in early-divergent green plants such as the Charophycean green algae. This study represents a comprehensive analysis of antheridium development and spermatogenesis in the green alga, Chara corallina. Microarrays of cell wall components and immunocytochemical methods were employed in order to analyse cell wall macromolecules during antheridium development. Cellulose and pectic homogalacturonan epitopes were detected throughout all cell types of the developing antheridium including the unique cell wall protuberances of the shield cells and the cell walls of sperm cell initials. Arabinogalactan protein epitopes were distributed only in the epidermal shield cell layers and anti-xyloglucan antibody binding was only observed in the capitulum region that initially yields the sperm filaments. During the terminal stage of sperm development, no cell wall polymers recognized by the probes employed were found on the scale-covered sperm cells. Antheridium development in C. corallina is a rapid event that includes the production of cell walls that contain polymers similar to those found in land plants. While pectic and cellulosic epitopes are ubiquitous in the antheridium, the distribution of arabinogalactan protein and xyloglucan epitopes is restricted to specific zones. Spermatogenesis also includes a major switch in the production of extracellular matrix macromolecules from cell walls to scales, the latter being a primitive extracellular matrix characteristic of green plants.

  2. [Modeling of hysteresis in pH pattern formation along the cell membrane of algae Chara corallina].

    Science.gov (United States)

    Lavrova, A I; Pliusnina, T Iu; Bulychev, A A; Riznichenko, G Iu; Rubin, A B

    2005-01-01

    It is known that illumination of the algae Chara corallina results in the formation along the membrane of regions with inhomogeneous distribution of pH. It was shown that, in a particular range of illumination intensities, two states with different pH distribution are realized at one and the same value of light intensity: an entirely homogeneous state and completely formed structures (pattern). The transition from the homogeneous state to the pattern formation takes place at one value of light intensity, and the back transition, at another light intensity, i.e., the hysteresis is observed. This phenomenon was studied by mathematical modeling. The mechanism of hysteresis is discussed.

  3. Bacillus cereus can attack the cell membranes of the alga Chara corallina by means of HlyII.

    Science.gov (United States)

    Kataev, Anatoly A; Andreeva-Kovalevskaya, Zhanna I; Solonin, Alexander S; Ternovsky, Vadim I

    2012-05-01

    We studied the influence of Bacillus cereus bacteria on cells of the freshwater alga Chara corallina. These bacteria and recombinant Bacillus subtilis strains are capable of producing the secreted toxin HlyII, which changes the electrophysiological parameters of the algal electrically excitable plasma membrane by forming pores. Cooperative incubation of bacterial cells, which carry active hlyII gene, and Chara corallina cells caused a decrease in the resting potential (V(m)) and plasma membrane resistance (R(m)) of algal cells. The efficiency of each strain was commensurable with its ability to produce HlyII. Purified hemolysin II caused a similar effect on V(m) and R(m) of intact and perfused cells. This protein changed the kinetics and magnitude of transient voltage-dependent calcium and calcium-activated chloride currents owing to the formation of additional Ca(2+)-permeable pores in algal cell membrane. Occurrence of the cellulose cell wall with pores 2.1 to 4.6nm in diameter suggests that HlyII molecules reach the plasma membrane surface strictly as monomers. Copyright © 2012 Elsevier B.V. All rights reserved.

  4. The effect of physical and chemical treatment on the mechanical properties of the cell wall of the alga Chara corallina.

    Science.gov (United States)

    Toole, Geraldine A; Smith, Andrew C; Waldron, Keith W

    2002-01-01

    Single large internode cells of the charophyte (giant alga) Chara corallina were dissected to give sheets of cell wall, which were then notched and their mechanical properties in tension determined. The cells were subjected to a thermal treatment in excess water (cf. cooking), which had little effect on strength but increased the stiffness, contrasting with the behaviour of higher-plant tissues. Extraction in CDTA (cyclohexane-trans-1,2-diamine-N,N,N',N'-tetraacetate) or 4 M KOH reduced the strength from 17 MPa to 10 MPa, although sequential extraction in CDTA and 4 M KOH reduced the strength further to 4 MPa. The stiffness decreased from 500 MPa to 300 MPa on extraction in CDTA or 4 M KOH, while falling to 70 MPa after extraction in CDTA followed by 4 M KOH. Conventional sequential extraction in CDTA, Na2CO3 at 1 degrees C and 20 degrees C, and KOH at 0.5 M, 1 M, 2 M and 4 M caused a gradual decrease in stiffness and strength after the CDTA treatment to the same lower values. This result is in keeping with mechanical properties for plant tissues, but in contrast to the removal of pectic polysaccharides from model cell wall systems, which does not reduce the stiffness.

  5. Protein phosphorylation regulates actomyosin-driven vesicle movement in cell extracts isolated from the green algae, Chara corallina.

    Science.gov (United States)

    Morimatsu, Miki; Hasegawa, Satoshi; Higashi-Fujime, Sugie

    2002-09-01

    In Characean cells endoplasmic streaming stops upon membrane depolarization accompanied by Ca(2+) entry. We investigated the mechanism of this cessation of endoplasmic streaming by reconstituting the vesicle movement in vitro. In a living cell of Chara corallina, there are a number of vesicles moving along actin cables. Vesicles in the endoplasm squeezed out of the cell into a medium containing Mg-ATP showed directional movements under a dark field microscope. When the extracted endoplasm was treated with 20 nM okadaic acid, vesicles showed only movements like the Brownian motion. When it was treated with 50 nM staurosporine, directional movements of vesicles were activated. These movements were analyzed by image processing of videomicroscopic records. Vesicle movements along F-actin filaments were also observed by merging both images of the same field by dark field microscopy and fluorescence microscopy, indicating that myosin on the vesicle surface was responsible for vesicle movements. We also examined the effects of okadaic acid and staurosporine on in vitro sliding of F-actin on Chara myosin. When Chara myosin was treated with 20 nM okadaic acid in the cell extract, the number of sliding F-actin filaments was greatly reduced. In contrast, it increased when Chara myosin was treated with 50 nM staurosporine. In addition, Chara myosin treated with protein kinase C greatly diminished its motility. These results suggest that inactivation of Chara myosin via its phosphorylation is responsible for cessation of endoplasmic streaming. Copyright 2002 Wiley-Liss, Inc.

  6. The statolith compartment in Chara rhizoids contains carbohydrate and protein

    Science.gov (United States)

    Wang-Cahill, F.; Kiss, J. Z.

    1995-01-01

    In contrast to higher plants, the alga Chara has rhizoids with single membrane-bound compartments that function as statoliths in gravity perception. Previous work has demonstrated that these statoliths contain barium sulfate crystals. In this study, we show that statoliths in Chara rhizoids react with a Coomassie Brilliant Blue cytochemical stain for proteins. While statoliths did not react with silver methenamine carbohydrate cytochemistry, the monoclonal antibody CCRC-M2, which is against a carbohydrate (sycamore-maple rhamnogalacturonan I), labeled the statolith compartment. These results demonstrate that in addition to barium sulfate, statoliths in Chara rhizoids have an organic matrix that consists of protein and carbohydrate moieties. Since the statoliths were silver methenamine negative, the carbohydrate in this compartment could be a 3-linked polysaccharide. CCRC-M2 also labeled Golgi cisternae, Golgi-associated vesicles, apical vesicles, and cell walls in the rhizoids. The specificity of CCRC-M2 immunolabeling was verified by several control experiments, including the demonstration that labeling was abolished when the antibody was preabsorbed with its antigen. Since in this and a previous study (John Z. Kiss and L. Andrew Staehelin, American Journal of Botany 80: 273-282, 1993) antibodies against higher plant carbohydrates crossreacted with cell walls of Chara in a specific manner, Characean algae may be a useful model system in biochemical and molecular studies of cell walls.

  7. Milliarcsecond Astronomy with the CHARA Array

    Science.gov (United States)

    Schaefer, Gail; ten Brummelaar, Theo; Gies, Douglas; Jones, Jeremy; Farrington, Christopher

    2018-01-01

    The Center for High Angular Resolution Astronomy offers 50 nights per year of open access time at the CHARA Array. The Array consists of six telescopes linked together as an interferometer, providing sub-milliarcsecond resolution in the optical and near-infrared. The Array enables a variety of scientific studies, including measuring stellar angular diameters, imaging stellar shapes and surface features, mapping the orbits of close binary companions, and resolving circumstellar environments. The open access time is part of an NSF/MSIP funded program to open the CHARA Array to the broader astronomical community. As part of the program, we will build a searchable database for the CHARA data archive and run a series of one-day community workshops at different locations across the country to expand the user base for stellar interferometry and encourage new scientific investigations with the CHARA Array.

  8. Algae

    Czech Academy of Sciences Publication Activity Database

    Raven, John A.; Giordano, Mario

    2014-01-01

    Roč. 24, č. 13 (2014), s. 590-595 ISSN 0960-9822 Institutional support: RVO:61388971 Keywords : algae * life cycle * evolution Subject RIV: EE - Microbiology, Virology Impact factor: 9.571, year: 2014

  9. Proteomic identification of putative plasmodesmatal proteins from Chara corallina.

    Science.gov (United States)

    Faulkner, Christine R; Blackman, Leila M; Cordwell, Stuart J; Overall, Robyn L

    2005-07-01

    Plasmodesmata are channels that bridge the cell walls of plant cells, allowing regulated transport of molecules between neighbouring cells. We have used a proteomic strategy to identify putative plasmodesmata-associated proteins in the giant-celled green alga Chara corallina. Proteins were extracted from the plasmodesmata-rich nodal complexes and the middle of the long internodal cells, which do not contain plasmodesmata. Comparison of protein spot patterns generated by two-dimensional gel electrophoresis of both the soluble and cell wall fractions from the two cell types was done. Fifty-eight spots that were common to the nodal and internodal soluble fractions were analysed by matrix assisted laser desorption/ionisation-time of flight mass spectrometry, and peptide mass fingerprint data were used to search the database. Matches were made to four of these spots, in each case to housekeeping proteins. Further, a number of nodal specific spots were identified, 11 from the soluble fraction and nine from the wall fraction. These spots were excised from the gels and analysed by liquid chromatography tandem mass spectrometry to obtain peptide sequence. Database searches suggest that these spots include homologues to previously identified plasmodesmata-associated proteins cp-wap13 and heat shock cognate 70, as well as RNA-binding proteins, eukaryotic initiation factor 4A and a beta-1,3-glucanase. Several spots remained unidentified providing exciting new candidate plasmodesmata-associated proteins.

  10. The Study of Algae

    Science.gov (United States)

    Rushforth, Samuel R.

    1977-01-01

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

  11. Auxin effects on ion transport in Chara corallina.

    Science.gov (United States)

    Zhang, Suyun; de Boer, Albertus H; van Duijn, Bert

    2016-04-01

    The plant hormone auxin has been widely studied with regard to synthesis, transport, signaling and functions among the land plants while there is still a lack of knowledge about the possible role for auxin regulation mechanisms in algae with "plant-like" structures. Here we use the alga Chara corallina as a model to study aspects of auxin signaling. In this respect we measured auxin on membrane potential changes and different ion fluxes (K(+), H(+)) through the plasma membrane. Results showed that auxin, mainly IAA, could hyperpolarize the membrane potential of C. corallina internodal cells. Ion flux measurements showed that the auxin-induced membrane potential change may be based on the change of K(+) permeability and/or channel activity rather than through the activation of proton pumps as known in land plants. Copyright © 2016 Elsevier GmbH. All rights reserved.

  12. DNA barcoding the genus Chara: molecular evidence recovers fewer taxa than the classical morphological approach.

    Science.gov (United States)

    Schneider, Susanne C; Rodrigues, Anuar; Moe, Therese Fosholt; Ballot, Andreas

    2015-04-01

    Charophytes (Charales) are benthic algae with a complex morphology. They are vulnerable to ecosystem changes, such as eutrophication, and are red-listed in many countries. Accurate identification of Chara species is critical for understanding their diversity and for documenting changes in species distribution. Species delineation is, however, complicated, because of high phenotypic plasticity. We used barcodes of the ITS2, matK and rbcL regions to test if the distribution of barcode haplotypes among individuals is consistent with species boundaries as they are currently understood. The study included freshly collected and herbarium material of 91 specimens from 10 European countries, Canada and Argentina. Results showed that herbarium specimens are useful as a source of material for genetic analyses for aquatic plants like Chara. rbcL and matK had highest sequence recoverability, but rbcL had a somewhat lower discriminatory power than ITS2 and matK. The tree resulting from the concatenated data matrix grouped the samples into six main groups contrary to a traditional morphological approach that consisted of 14 different taxa. A large unresolved group consisted of C. intermedia, C. hispida, C. horrida, C. baltica, C. polyacantha, C. rudis, C. aculeolata, and C. corfuensis. A second unresolved group consisted of C. virgata and C. strigosa. The taxa within each of the unresolved groups shared identical barcode sequences on the 977 positions of the concatenated data matrix. The morphological differences of taxa within both unresolved groups include the number and length of spine cells, stipulodes, and bract cells. We suggest that these morphological traits have less taxonomic relevance than hitherto assumed. © 2015 Phycological Society of America.

  13. BIODIVERSITY OF CORALLINE ALGAE IN THE NORTHEASTERN ATLANTIC INCLUDING CORALLINA CAESPITOSA SP. NOV. (CORALLINOIDEAE, RHODOPHYTA)(1).

    Science.gov (United States)

    Walker, Rachel H; Brodie, Juliet; Russell, Stephen; Irvine, Linda M; Orfanidis, Sotiris

    2009-02-01

    The Corallinoideae (Corallinaceae) is represented in the northeastern Atlantic by Corallina officinalis L.; Corallina elongata J. Ellis et Sol.; Haliptilon squamatum (L.) H. W. Johans., L. M. Irvine et A. M. Webster; and Jania rubens (L.) J. V. Lamour. The delimitation of these geniculate coralline red algae is based primarily on morphological characters. Molecular analysis based on cox1 and 18S rRNA gene phylogenies supported the division of the Corallinoideae into the tribes Janieae and Corallineae. Within the Janieae, a sequence difference of 46-48 bp (8.6%-8.9%) between specimens of H. squamatum and J. rubens in the cox1 phylogeny leads us to conclude that they are congeneric. J. rubens var. rubens and J. rubens var. corniculata (L.) Yendo clustered together in both phylogenies, suggesting that for those genes, there was no genetic basis for the morphological variation. Within the Corallineae, it appears that in some regions, the name C. elongata has been misapplied. C. officinalis samples formed two clusters that differed by 45-54 bp (8.4%-10.0%), indicating species-level divergence, and morphological differences were sufficient to define two species. One of these clusters was consistent with the morphology of the type specimen of C. officinalis (LINN 1293.9). The other species cluster is therefore described here as Corallina caespitosa sp. nov. This study has demonstrated that there is a clear need for a revision of the genus Corallina to determine the extent of "pseudocryptic" diversity in this group of red algae. © 2009 Phycological Society of America.

  14. Fracture mechanics of the cell wall of Chara corallina.

    Science.gov (United States)

    Toole, G A; Gunning, P A; Parker, M L; Smith, A C; Waldron, K W

    2001-03-01

    Previous mechanical studies using algae have concentrated on cell extension and growth using creep-type experiments, but there appears to be no published study of their failure properties. The mechanical strength of single large internode cell walls (up to 2 mm diameter and 100 mm in length) of the charophyte (giant alga) Chara corallina was determined by dissecting cells to give sheets of cell wall, which were then notched and fractured under tension. Tensile tests, using a range of notch sizes, were conducted on cell walls of varying age and maturity to establish their notch sensitivity and to investigate the propagation of cracks in plant cell walls. The thickness and stiffness of the walls increased with age whereas their strength was little affected. The strength of unnotched walls was estimated as 47+/-13 MPa, comparable to that of some grasses but an order of magnitude higher than that published for model bacterial cellulose composite walls. The strength was notch-sensitive and the critical stress intensity factor K1c was estimated to be 0.63+/-0.19 MNm(-3/2), comparable to published values for grasses.

  15. Distribution of inorganic elements in single cells of Chara corallina

    International Nuclear Information System (INIS)

    Li Zijie; Zhang Zhiyong; Chai Zhifang; Yu Ming; Zhou Yunlong

    2005-01-01

    There are actually 20 chemical elements necessary or beneficial for plant growth. Carbon, hydrogen, and oxygen are supplied by air and water. The six macronutrients, nitrogen, phosphorus, potassium., calcium, magnesium, and sulfur are required by plants in large amounts. The rest of the elements are required in trace amounts (micronutrients). Essential trace elements include boron, chlorine, copper, iron, manganese, sodium, zinc, molybdenum, and nickel. Beneficial mineral elements include silicon and cobalt. The functions of the inorganic elements closely related to their destinations in plant cells. Plant cells have unique structures, including a central vacuole, plastids, and a thick cell wall that surrounds the cell membrane. Generally, it is very difficult to determine concentrations of inorganic elements in a single plant cell. Chara corallina is a freshwater plant that inhabits temperate zone ponds and lakes. It consists of alternating nodes and internodes. Each internodal segment is a single large cell, up to 10 cm in length, and 1 mm in diameter. With this species it was possible to isolate subcellular fractions with surgical methods with minimal risk of cross contamination. In this study, concentrations of magnesium, calcium, manganese, iron, copper, zinc, and molybdenum in the cell wall, cytoplasm, and vacuole of single cells of Chara corallina were determined by inductively coupled plasma mass spectrometry (ICP-MS). The distribution characteristics of these elements in the cell components were discussed.

  16. Chara strigosa A. Braun (Characeae in Poland

    Directory of Open Access Journals (Sweden)

    Andrzej Hutorowicz

    2014-01-01

    Full Text Available Chara strigosa is reported from several lakes in Poland. The finds were published by Izabella Dąmbska in 1966, but have not been recognised internationally, presumably because Dąmbska's article was published in a local paper in Polish. We give a short description of Charetum strigosa first described by Dąmbska. One of the lakes with C. strigosa is reported with luxuriant growth of a blue-green bacteria common in water blooms. There is a need to survey these lakes in order to prevent an increasing eutrophication.

  17. Mechanisms of cobalt uptake in plants: 60Co uptake and distribution in Chara

    International Nuclear Information System (INIS)

    Liu, J.; Reid, R.J.; Smith, F.A.

    1998-01-01

    The mechanism of cobalt uptake was investigated using cells of the giant alga Chara corallina in which it is possible to resolve separately uptake by the cell wall and actual influx across the cell membrane. The absorption of 60 Co by Chara cells appeared to saturate within 2 h. but this was mainly due to rapid uptake into the cell wall which accounted for 87-92% of the total activity. Even after prolonged desorption most of the cell-associated 60 Co was found on the cell wall. The intracellular distribution of absorbed 60 Co was investigated by fractionating the cell into cytoplasm and vacuole. It was shown that 60 Co influx to the vacuole occurs simultaneously with influx to the cytoplasm. The transported species appears to be Co 2+ rather than the less charged Co(OH) + or Co(O) 2 . 60 Co influx is pH dependent (optimum pH 7-9), and is sensitive to some other divalent metals. Influx from solutions containing 1 μM 60 Co was inhibited by 5 μM Cd 2+ , Cu 2+ , and Zn 2+ , but Mn 2+ and Ni 2+ had no significant effect. The sensitivity of Co uptake to N-ethyl maleimide (NEM) and cysteine suggests that the transport system involves direct binding of Co 2+ to -SH groups. (au)

  18. Circumnutation in the growth of Chara rhizoids

    Directory of Open Access Journals (Sweden)

    Marek Bełtowski

    2014-01-01

    Full Text Available Chara rhizoids, cylindrical cells growing in their apex, having the capability of positive orthogravitropic response, while growing without any change of position are not ideally straight, but they are characterised by slight and repeating cyclic bendings. The mean distance between successive bendings is 150 µm. The bendings appear more or less every 1.5 hour at rhizoids' growth rate of about 100 µm h-1. After the displacement of the rhizoids from the vertical to the horizontal position, during the gravireaction, the curvature proceeds in stages, in which, alternatingly, there appear periods of higher or lower curvature. The curvature of successive higher bendings decreases when the rhizoid reaches the vertical direction. It seems that gravireaction is based on the increase of the maximal curvature of cyclic bendings and directing the bendings into a vertical plane. Other tip growing cells, generally straight, such as root hairs or hyphae of Mucor and Phycomyces, also show the repeating bendings.

  19. Pushing CHARA to its Limit: A Pathway Toward 80X80 Pixel Images of Stellar Surfaces

    Science.gov (United States)

    Norris, Ryan

    2018-04-01

    Imagine a future with 80x80 pixel images of stellar surfaces. With a maximum baseline of 330 m, the CHARA Array is already capable of achieving 0.5 mas resolution, sufficient for imaging the red supergiant Betelgeuse (d = 42.3 mas ) at such a scale. However several issues have hampered attempts to image the largest stars at CHARA, including a lack of baselines shorter than 34 m and instrument sensitivities unable to measure the faintest fringes. Here we discuss what is needed to achieve imaging of large stars at CHARA. We will present suggestions for future telescope placement, describing the advantages of a short baseline, while also considering the needs of other imaging targets that might benefit from additional baselines. We will also present developments in image reconstruction methods that can improve the resolution of images today, albeit of smaller targets and at a lesser scale. Of course, there will be example images, created using simulated oifits data and state of the art reconstruction techniques!

  20. Algae Resources

    Energy Technology Data Exchange (ETDEWEB)

    None

    2016-06-01

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

  1. Distribution of Chara braunii Gmellin 1826 (Charophyta in Poland

    Directory of Open Access Journals (Sweden)

    Jacek Urbaniak

    2011-01-01

    Full Text Available The distribution and ecology of Chara braunii Gmellin 1826 in Poland is described, based on herbaria collections, literature data and own investigations. Maps showing the distribution of Ch. braunii are presented, as well as a list of localities with brief descriptions of the habitats. Additionally, some remarks on the distribution limit in the northern hemisphere are given.

  2. Calcium pectate chemistry controls growth rate of Chara corallina.

    Science.gov (United States)

    Proseus, Timothy E; Boyer, John S

    2006-01-01

    Pectin, a normal constituent of cell walls, caused growth rates to accelerate to the rates in living cells when supplied externally to isolated cell walls of Chara corallina. Because this activity was not reported previously, the activity was investigated. Turgor pressure (P) was maintained in isolated walls or living cells using a pressure probe in culture medium. Pectin from various sources was supplied to the medium. Ca and Mg were the dominant inorganic elements in the wall. EGTA or pectin in the culture medium extracted moderate amounts of wall Ca and essentially all the wall Mg, and wall growth accelerated. Removing the external EGTA or pectin and replacing with fresh medium returned growth to the original rate. A high concentration of Ca2+ quenched the accelerating activity of EGTA or pectin and caused gelling of the pectin, physically inhibiting wall growth. Low pH had little effect. After the Mg had been removed, Ca-pectate in the wall bore the longitudinal load imposed by P. Removal of this Ca caused the wall to burst. Live cells and isolated walls reacted similarly. It was concluded that Ca cross-links between neighbouring pectin molecules were strong wall bonds that controlled wall growth rates. The central role of Ca-pectate chemistry was illustrated by removing Ca cross-links with new pectin (wall "loosening"), replacing vacated cross-links with new Ca2+ ("Ca2+-tightening"), or adding new cross-links with new Ca-pectate that gelled ("gel tightening"). These findings establish a molecular model for growth that includes wall deposition and assembly for sustained growth activity.

  3. Taxonomic significance of micromorphology and dimensions of oospores in the genus Chara L., Charales, Chlorophyta

    Directory of Open Access Journals (Sweden)

    Mandal D.K.

    2004-01-01

    Full Text Available Oospore wall ornamentation patterns as revealed by scanning electron microscopy (SEM provide important taxonomic characters in the Charales. The present study illustrates inter- and intra-specific variations in the oospore wall ornamentation of five species of Chara, including eight intra-specific taxa. The type variety and form of C. globularis shows pusticular elevations with pores at the base of the elevation. The variety and form aspera of C. globularis shows a porous oospore wall, and the oospore is provided with a ribbon which bears nearly granular ornamentation. The type form of C. setosa has a granular oospore wall. The three forms of C. braunii show a similar type of ornamentation and support their placement under a single species. Chara corallina has a roughened oospore wall. Oospore dimensions studied at the population level are another feature included in the present study. The oospore dimension data (length, width fossa-breadth, number of striae at the population level were analyzed statistically, and the results show species-specificity of these parameters. The significance of oospore wall ornamentation and dimensions are discussed simultaneously with morphological features.

  4. Biogas production experimental research using algae.

    Science.gov (United States)

    Baltrėnas, Pranas; Misevičius, Antonas

    2015-01-01

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

  5. soil algae

    African Journals Online (AJOL)

    Timothy Ademakinwa

    Also, the importance of algae in soil formation and soil fertility improvement cannot be over emphasized as the world is working ... farms further establishes the role of blue green algae in soil nutrients for plant growth. Key words- Soil Fertility, Soil ... with sunlight will promote the growth of soil algae and their contribution to ...

  6. Interactions of light and gravity in Chara internodal cells

    Science.gov (United States)

    Staves, Mark P.; Whitsit, Kimberly; Yeung, Edward

    2005-08-01

    The "shoots" of Chara corallina are composed of large (ca. 2-5 cm length and 0.5 mm diameter) internodal cells alternating with smaller, node-forming cells. We find that these shoots are both negatively gravitropic as well as positively phototropic. Differential growth in response to both gravity and light typically takes place in the two most apical (youngest) internodal cells, however the plants can be manipulated so that all curvature takes place in a single cell. We grew Chara in aquaria filled with artificial pond water with their rhizoids in 35 mm film canisters containing soil. Thus, it was easy to reorient the axis of the plant with respect to gravity. Experimental plants were allowed to develop to a stage where they had one or two visible internodal cells. In the absence of light, internodal cells are negatively gravitropic. If gravistimulated (horizontal) internodal cells are illuminated with white light from above, gravity and light act together and more rapid curvature ensues. If however, gravistimulated internodal cells are illuminated from below, gravity and light act antagonistically and light can overcome the gravity signal. We find that gravistimulated cells illuminated from below will bend up (i.e. negatively gravitropic and negatively phototropic) at light intensities below ca. 1 μmol m-2 s-1 whereas they curve downward (positively gravitropic and positively phototropic) at higher light intensities. Preliminary studies indicate that both blue and green light stimulate phototropism whereas red light is not effective. Chara thus provides a system in which a single, statolith-free cell responds to both light and gravity and in which the interactions of the light- and gravity-induced signal transduction pathways can be investigated.

  7. Classification of planctonema-like algae, including a new genus Planctonemopsis gen. nov., a new species Planctonema gelatinosum sp. nov. and a reinstated genus Psephonema (Trebouxiophyceae, Chlorophyta).

    Science.gov (United States)

    Liu, Xudong; Zhu, Huan; Liu, Benwen; Liu, Guoxiang; Hu, Zhengyu

    2017-08-01

    Planctonema-like species consist of planktonic green algae and are found throughout the world. Their characteristic morphology, which includes short and slender filaments consisting of side-by-side or distant cylindrical cells enclosed in a fine and hyaline sheath, makes them easily distinguishable. To date, Planctonema lauterbornii was the only taxon accepted for this group. However, descriptions from different materials have revealed notable morphological differences, including the presence/absence of a pyrenoid, a mucilage sheath and an apical thickening of the cell wall. In this study, six strains of Planctonema-like species were identified and successfully cultured in the laboratory. We used a molecular approach to determine their taxonomic relationships and phylogenetic positions. The molecular analysis resolved them to at least three genera. The genus Planctonema was positioned in Trebouxiophyceae as an incertae sedis taxon that is closely related to Oocystaceae and was divided into two species. Planctonema gelatinosum was determined to be a new species with approximately twice the width and a thicker mucilage sheath, which differentiated it from the type species Planctonema lauterbornii. The genus Psephonema was reinstated based on 1.5-2 times length-width ratio than Planctonema and the big difference on the rbcL cpDNA gene marker and an intron insertion in the 18S rDNA. A new genus, Planctonemopsis, which represents the pyrenoid-present strains among the Planctonema-like species, was established. Planctonemopsis was positioned within Oocystaceae as a new clade and is distantly related to the other two genera. Taxonomic diversity was proven by distinctive morphological differences and phylogenetic divergence in the Planctonema-like group identified herein. © 2017 Phycological Society of America.

  8. Analysis of Statoliths Displacement in Chara Rhizoids for Validating the Microgravity-Simulation Quality of Clinorotation Modes

    Science.gov (United States)

    Krause, Lars; Braun, Markus; Hauslage, Jens; Hemmersbach, Ruth

    2018-01-01

    In single-celled rhizoids of the green algae Chara, positively gravitropic growth is governed by statoliths kept in a dynamically stable position 10-25 μ m above the cell tip by a complex interaction of gravity and actomyosin forces. Any deviation of the tube-like cells from the tip-downward orientation causes statoliths to sediment onto the gravisensitive subapical cell flank which initiates a gravitropic curvature response. Microgravity experiments have shown that abolishing the net tip-directed gravity force results in an actomyosin-mediated axial displacement of statoliths away from the cell tip. The present study was performed to critically assess the quality of microgravity simulation provided by different operational modes of a Random Positioning Machine (RPM) running with one axis (2D mode) or two axes (3D mode) and different rotational speeds (2D), speed ranges and directions (3D). The effects of 2D and 3D rotation were compared with data from experiments in real microgravity conditions (MAXUS sounding rocket missions). Rotational speeds in the range of 60-85 rpm in 2D and 3D modes resulted in a similar kinetics of statolith displacement as compared to real microgravity data, while slower clinorotation (2-11 rpm) caused a reduced axial displacement and a more dispersed arrangement of statoliths closer to the cell tip. Increasing the complexity of rotation by adding a second rotation axis in case of 3D clinorotation did not increase the quality of microgravity simulation, however, increased side effects such as the level of vibrations resulting in a more dispersed arrangement of statoliths. In conclusion, fast 2D clinorotation provides the most appropriate microgravity simulation for investigating the graviperception mechanism in Chara rhizoids, whereas slower clinorotation speeds and rotating samples around two axes do not improve the quality of microgravity simulation.

  9. Seasonal variation in invertebrate grazing on Chara connivens and C. tomentosa in Kõiguste Bay, NE Baltic Sea

    Science.gov (United States)

    Kotta, Jonne; Torn, Kaire; Martin, Georg; Orav-Kotta, Helen; Paalme, Tiina

    2004-04-01

    Charophytes are a highly endangered group of algae. In the Baltic Sea, the number of species, distribution area and biomass of charophytes have significantly decreased in recent decades. Although eutrophication triggers their initial decline, the mechanism of the final extinction of charophyte populations is not fully understood. An in situ experiment was performed to study the role of the mesoherbivores Idotea baltica, Gammarus oceanicus and Palaemon adspersus in the decline of charophytes in the north-eastern Baltic Sea. Invertebrate grazing showed a clear seasonality: grazing pressure was low in April, moderate in July, and high in October. Grazing on charophytes by P. adspersus was negligible, whereas I. baltica and G. oceanicus significantly reduced the biomass of charophytes in the field. Low photosynthetic activity (high decomposition rate) of the charophytes favoured grazing. The invertebrates studied preferred Chara tomentosa to C. connivens. Low consumption of C. connivens may reflect its non-native origin. The experiment suggests that, under moderately eutrophic conditions, grazers are not likely to control charophyte populations. However, grazers have the potential to eliminate charophytes in severely eutrophic systems under the stress of filamentous algae.

  10. Through pore diameter in the cell wall of Chara corallina.

    Science.gov (United States)

    Berestovsky, G N; Ternovsky, V I; Kataev, A A

    2001-06-01

    Determination of pore size of the cell wall of Chara corallina has been made by using the polyethylene glycol (PEG) series as the hydrophilic probing molecules. In these experiments, the polydispersity of commercial preparation of PEGs was allowed for. The mass share (gamma(p)) of polyethylene glycol preparation fractions penetrating through the pores was determined using a cellular 'ghost', i.e. fragments of internodal cell walls filled with a 25% solution of non-penetrating PEG 6000 and tied up at the ends. In water, such a 'ghost' developed a hydrostatic pressure close to the cell turgor which persisted for several days. The determination of gamma(p), for polydisperse polyethylene glycols with different average molecular mass (M) was calculated from the degree of pressure restoration after water was replaced by a 5-10% polymer solution. Pressure was recorded using a dynamometer, which measures, in the quasi-isometric mode, the force necessary for the partial compression of the 'ghost' in its small fragment. By utilizing the data on the distribution of PEG 1000, 1450, 2000, and 3350 fractions over molecular mass (M), it was found that gamma(p), for these polyethylene glycols corresponded to the upper limit of ML=800-1100 D (hydrodynamic radius of molecules, r(h)=0.85-1.05 nm). Thus, the effective diameter of the pores in the cell wall of Chara did not exceed 2.1 nm.

  11. LC-MS/APCI identification of glucoside esters and diesters of astaxanthin from the snow alga Chlamydomonas nivalis including their optical stereoisomers

    Czech Academy of Sciences Publication Activity Database

    Řezanka, Tomáš; Nedbalová, Linda; Kolouchová, I.; Sigler, Karel

    2013-01-01

    Roč. 88, APR 2013 (2013), s. 34-42 ISSN 0031-9422 R&D Projects: GA ČR(CZ) GAP503/11/0215 Institutional support: RVO:61388971 ; RVO:67985939 Keywords : Chlamydomonas nivalis * Snow alga * Austrian Alps Subject RIV: CE - Biochemistry; EF - Botanics (BU-J) Impact factor: 3.350, year: 2013

  12. Calcium deprivation disrupts enlargement of Chara corallina cells: further evidence for the calcium pectate cycle.

    Science.gov (United States)

    Proseus, Timothy E; Boyer, John S

    2012-06-01

    Pectin is a normal constituent of cell walls of green plants. When supplied externally to live cells or walls isolated from the large-celled green alga Chara corallina, pectin removes calcium from load-bearing cross-links in the wall, loosening the structure and allowing it to deform more rapidly under the action of turgor pressure. New Ca(2+) enters the vacated positions in the wall and the externally supplied pectin binds to the wall, depositing new wall material that strengthens the wall. A calcium pectate cycle has been proposed for these sub-reactions. In the present work, the cycle was tested in C. corallina by depriving the wall of external Ca(2+) while allowing the cycle to run. The prediction is that growth would eventually be disrupted by a lack of adequate deposition of new wall. The test involved adding pectate or the calcium chelator EGTA to the Ca(2+)-containing culture medium to bind the calcium while the cycle ran in live cells. After growth accelerated, turgor and growth eventually decreased, followed by an abrupt turgor loss and growth cessation. The same experiment with isolated walls suggested the walls of live cells became unable to support the plasma membrane. If instead the pectate or EGTA was replaced with fresh Ca(2+)-containing culture medium during the initial acceleration in live cells, growth was not disrupted and returned to the original rates. The operation of the cycle was thus confirmed, providing further evidence that growth rates and wall biosynthesis are controlled by these sub-reactions in plant cell walls.

  13. Turgor, temperature and the growth of plant cells: using Chara corallina as a model system.

    Science.gov (United States)

    Proseus, T E; Zhu, G L; Boyer, J S

    2000-09-01

    Rapid changes in turgor pressure (P:) and temperature (T:) are giving new information about the mechanisms of plant growth. In the present work, single internode cells of the large-celled alga Chara corallina were used as a model for plant growth. P was changed without altering the chemical environment of the wall while observing growth without elastic changes. When P: was measured before any changes, the original growth rate bore no relationship to the original P. However, if P of growing cells was decreased, growth responded immediately without evidence for rapid changes in wall physical properties. Growth occurred only above a 0.3 MPa threshold, and increasing P caused small increases in growth that became progressively larger as P rose, resulting in a curvilinear response overall. The small changes in growth close to the threshold may explain early failures to detect these responses. When T was lowered, the elastic properties of the cell were unaffected, but growth was immediately inhibited. The lower T caused P to decrease, but returning P to its original value did not return growth to its original rate. The decreased P at low T occurred because of T effects on the osmotic potential of the cell. At above-normal P, growth partially resumed at low T Therefore, growth required a P-sensitive process that was also T-sensitive. Because elastic properties were little affected by T, but growth was markedly affected, the process is likely to involve metabolism. The rapidity of its response to P and T probably excludes the participation of changes in gene expression.

  14. Tension required for pectate chemistry to control growth in Chara corallina.

    Science.gov (United States)

    Proseus, Timothy E; Boyer, John S

    2007-01-01

    Recent work showed that polygalacturonate (pectate) chemistry controlled the growth rate of the large-celled alga Chara corallina when turgor pressure (P) was normal (about 0.5 MPa). The mechanism involved calcium withdrawal from the wall by newly supplied pectate acting as a chelator. But P itself can affect growth rate. Therefore, pectate chemistry was investigated at various P. A pressure probe varied P in isolated walls, varying the tension on the calcium pectate cross-links bearing the load of P. When soluble pectate was newly supplied, the wall grew irreversibly but the pectate was inactive below a P of 0.2 MPa, indicating that tension was required in the existing wall before new pectate acted. It was suggested that the tension distorted some of the wall pectate (the dominant pectin), weakening its calcium cross-links and causing the calcium to be preferentially lost to the new pectate, which was not distorted. The preferential loss provided a molecular mechanism for loosening the wall structure, resulting in faster growth. However, the resulting relaxation of the vacated wall pectate would cause calcium to be exchanged with load-bearing calcium pectate nearby, auto-propagating throughout the wall for long periods. There is evidence for this effect in isolated walls. In live cells, there is also evidence that auto-propagation is controlled by binding the newly supplied pectate (now calcium pectate) to the wall and/or by additional Ca(2+) entering the wall structure. A tension-dependent cycle of pectate chemistry thus appeared to control growth while new wall was deposited as a consequence.

  15. c-Ha-ras BamHI RFLP in human urothelial tumors and point mutations in hot codons

    International Nuclear Information System (INIS)

    Weismanova, E; Skovraga, M.; Kaluz, S.

    1993-01-01

    High-molecular weights DNAs from 30 bladder and renal cell carcinomas (RCC) were isolated and the c-Ha-ras the c-Ha-ras gene BamHI RFLP was examined. Amplification of c-Ha-ras with normal localization with regard to the size of alleles was found only in the case. One of the normally localized c-Ha-ras allele termed RCC c-H-ras of a length of about 6.6 kbp was cloned and an oncogene-activating point mutation was identified using two restriction enzymes. After comparison of CfrI and Cfr10I cleavage maps of RCC c-Ha-ras to complete nucleotide sequences of EJ/T24 c-Ha-ras oncogene and its normal counterpart, a point mutation was identified within codon 11 or 12. The use of CfrI and Cfr10I is of value for clinical practice in identification of point mutations in c-Ha-ras PCR product in neoplasia accompanied by somatic mutation of c-Ha-ras. The correlation among c-Ha-ras allele, amplification/loss, presence of point mutation and progression of neoplasia is discussed. (author)

  16. Microscopic Gardens: A Close Look at Algae.

    Science.gov (United States)

    Foote, Mary Ann

    1983-01-01

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

  17. The effect of the external medium on the gravity-induced polarity of cytoplasmic streaming in Chara corallina (Characeae)

    Science.gov (United States)

    Staves, M. P.; Wayne, R.; Leopold, A. C.

    1997-01-01

    Gravity induces a polarity of cytoplasmic streaming in vertical internodal cells of Chara such that the downwardly directed stream moves faster than the upwardly directed stream. In order to determine whether the statolith theory (in which intracellular sedimenting particles are responsible for gravity sensing) or the gravitational pressure theory (in which the entire protoplast acts as the gravity sensor) best explain the gravity response in Chara internodal cells, we controlled the physical properties of the external medium, including density and osmolarity, with impermeant solutes and examined the effect on the polarity of cytoplasmic streaming. As the density of the external medium is increased, the polarity of cytoplasmic streaming decreases and finally disappears when the density of the external medium is equal to that of the cell (1015 kg/m3). A further increase in the density of the external medium causes a reversal of the gravity response. These results are consistent with the gravitational pressure theory of gravity sensing since the buoyancy of the protoplast is dependent on the difference between the density of the protoplast and the external medium, and are inconsistent with the statolith theory since the buoyancy of intracellular particles are unaffected by changes in the external medium.

  18. An unexpectedly large and loosely packed mitochondrial genome in the charophycean green alga Chlorokybus atmophyticus

    Directory of Open Access Journals (Sweden)

    Lemieux Claude

    2007-05-01

    Full Text Available Abstract Background The Streptophyta comprises all land plants and six groups of charophycean green algae. The scaly biflagellate Mesostigma viride (Mesostigmatales and the sarcinoid Chlorokybus atmophyticus (Chlorokybales represent the earliest diverging lineages of this phylum. In trees based on chloroplast genome data, these two charophycean green algae are nested in the same clade. To validate this relationship and gain insight into the ancestral state of the mitochondrial genome in the Charophyceae, we sequenced the mitochondrial DNA (mtDNA of Chlorokybus and compared this genome sequence with those of three other charophycean green algae and the bryophytes Marchantia polymorpha and Physcomitrella patens. Results The Chlorokybus genome differs radically from its 42,424-bp Mesostigma counterpart in size, gene order, intron content and density of repeated elements. At 201,763-bp, it is the largest mtDNA yet reported for a green alga. The 70 conserved genes represent 41.4% of the genome sequence and include nad10 and trnL(gag, two genes reported for the first time in a streptophyte mtDNA. At the gene order level, the Chlorokybus genome shares with its Chara, Chaetosphaeridium and bryophyte homologues eight to ten gene clusters including about 20 genes. Notably, some of these clusters exhibit gene linkages not previously found outside the Streptophyta, suggesting that they originated early during streptophyte evolution. In addition to six group I and 14 group II introns, short repeated sequences accounting for 7.5% of the genome were identified. Mitochondrial trees were unable to resolve the correct position of Mesostigma, due to analytical problems arising from accelerated sequence evolution in this lineage. Conclusion The Chlorokybus and Mesostigma mtDNAs exemplify the marked fluidity of the mitochondrial genome in charophycean green algae. The notion that the mitochondrial genome was constrained to remain compact during charophycean

  19. Ultrastructural, autoradiographic and electrophoretic examinations of Chara tomentosa spermiogenesis

    Directory of Open Access Journals (Sweden)

    Maria Kwiatkowska

    2014-01-01

    Full Text Available Ultrastructure of a spermatid nucleus changes many times during spermiogenesis. Condensed chromatin forms irregular clusters during phases I-II, a continuous ring adjacent to a nuclear envelope during phases III-V and a network occupying the whole nucleus during phase VI. In advanced spermiogenesis dense chromatin disappears and short randomly positioned fibrils arise, then long parallel ones are found (phase VIII which during phase IX form a lamellar structure. In mature spermatozoids (phase X chromatin becomes extremely condensed. 3H-arginine and 3H-lysine incorporation into spermatids during 2-min incubation is intensive during phases IN, decreases during phases VI, VII and becomes very low during phases VIII-IX. Capillary electrophoresis has shown that during Chara tomentosa spermiogenesis replacement of histones with basic proteins whose mobility is comparable to that of salmon protamines takes place. At the beginning of spermiogenesis core and linker histones are found in spermatids. During early spermiogenesis protamine-like proteins appear and their amount increases in late spermiogenesis when core histones are still present. In mature spermatozoids only protamine-like proteins represented by 3 fractions: 9.1 kDa, 9.6 kDa, 11.2 kDa are found. Disappearance of linker histones following their modification precedes disappearance of core histones. The results indicate that dynamic rearrangement of chromatin ultrastructure and aminoacid incorporation rate during spermiogenesis are reflected in basic nuclear protein changes.

  20. The motility of Chara corallina myosin was inhibited reversibly by 2,3-butanedione monoxime (BDM).

    Science.gov (United States)

    Funaki, Keisuke; Nagata, Ayumi; Akimoto, Youka; Shimada, Kiyo; Ito, Kohji; Yamamoto, Keiichi

    2004-09-01

    We studied the effects of 2,3-butanedione monoxime (BDM) on the cytoplasmic streaming of Chara corallina and on the motility of myosin prepared from the same plant to examine whether this reagent really affects the plant class XI myosin. It was found that BDM inhibited both cytoplasmic streaming and the motility of myosin at a very similar concentration range (10-100 mM). BDM introduced directly into tonoplast-free cells also inhibited cytoplasmic streaming. These results suggested that effect of BDM on cytoplasmic streaming was exerted through myosin and not through ion channels at least in Chara corallina, though a very high concentration of BDM was required.

  1. The density of the cell sap and endoplasm of Nitellopsis and Chara

    Science.gov (United States)

    Wayne, R.; Staves, M. P.

    1991-01-01

    We measured the densities of the cell sap, endoplasm and cell wall of Nitellopsis obtusa and Chara corallina using interference microscopy, refractometry, immersion refractometry, equilibrium sedimentation and chemical microanalysis techniques. These values are important for the determination of many rheological properties of the cytoplasm as well as for understanding buoyancy regulation, dispersal mechanisms and how cells respond to gravity. The average densities of the cell sap, endoplasm and cell wall are 1,006.9, 1,016.7 and 1,371 kg m-3 for Nitellopsis and 1,005.0, 1,013.9, and 1,355.3 kg m-3 for Chara.

  2. Microinjected magnetic beads induce curvature in Chara rhizoids

    Science.gov (United States)

    Scherp, P.; Hasenstein, K.

    The gravitropic response of the Chara rhizoid is based on the interaction between the statoliths and the actin network located in the rhizoid apex. The rhizoid represents a model system for the study of gravitropism, because its apical cell contains the gravity sensing and response mechanism. In order to study the function of the statoliths and the cytoskeleton, we supplemented the naturally occurring statoliths with magnetic beads. These beads can be moved by an external magnetic field and they can be coated to interact with the cytoskeleton. The magnetic beads (1μm diameter) were injected close to the tip of the rhizoid in the presence of an external osmoticum to offset turgor pressure. The injection caused the formation of a noticeable plug of dense material at the site of impalement. After a recovery period of ca. 2 - 4 hours, the whole plant was mounted on the rotatable stage of a custom- built horizontal microscope, equipped with a long-working distance objective and a video camera. This stage is designed to reorientate the cell and/or the injected beads. In order to study the effect of the displacement of magnetic beads, an external magnetic field was applied. This external field was capable of displacing the magnetic particles but did not affect the natural statoliths. Work is in progress to quantify the response, to study the effect of microinjection on wall formation, and utilize coating of the beads to investigate their possible interaction with the original statoliths and with the microfilament network. Supported by NASA grant NAG 2- 1423.

  3. Involvement of membrane potential in alkaline band formation by internodal cells of Chara corallina.

    Science.gov (United States)

    Shimmen, Teruo; Wakabayashi, Akiko

    2008-10-01

    Internodal cells of Chara corallina form alkaline bands on their surface upon illumination via photosynthesis. In the present study, the effect of KCl on alkaline band formation was analyzed. When the extracellular KCl concentration was increased, alkaline band formation was extensively inhibited. Electrophysiological analysis unequivocally showed the need for inner negative membrane potential for alkaline band formation.

  4. Anion channels in Chara corallina tonoplast membrane: Calcium dependence and rectification

    NARCIS (Netherlands)

    Berecki, G.; Varga, Z.; Iren, F. van; Duijn, B. van

    1999-01-01

    Tonoplast K+ channels of Chara corallina are well characterized but only a few reports mention anion channels, which are likely to play an important role in the tonoplast action potential and osmoregulation of this plant. For experiments internodal cells were isolated. Cytoplasmic droplets were

  5. Insight into the mechanism of fast movement of myosin from Chara corallina.

    Science.gov (United States)

    Sumiyoshi, Hiroki; Ooguchi, Masami; Ooi, Atsushi; Okagaki, Tsuyoshi; Higashi-Fujime, Sugie

    2007-02-01

    Chara myosin, two-headed plant myosin belonging to class XI, slides F-actin at maximally 60 microm s(-1). To elucidate the mechanism of this fast sliding, we extensively investigated its mechanochemical properties. The maximum actin activated ATPase activity, Vmax, was 21.3 s(-1) head(-1) in a solution, but when myosin was immobilized on the surface, its activity was 57.6 s(-1) head(-1) at 2 mg ml(-1) of F-actin. The sliding velocity and the actin activated ATPase activity were greatly inhibited by ADP, suggesting that ADP dissociation was the rate limiting step. With the extensive assay of motility by varying the surface density, the duty ratio of Chara myosin was found to be 0.49-0.44 from velocity measurements and 0.34 from the landing rate analysis. At the surface density of 10 molecules microm(-2), Chara myosin exhibited pivot movement under physiological conditions. Based on the results obtained, we will discuss the sliding mechanism of Chara myosin according to the working stroke model in terms of its physiological aspects. aspects. (c) 2006 Wiley-Liss, Inc.

  6. CHARA Array K'-Band Measurements of the Angular Dimensions of Be Star Disks

    Czech Academy of Sciences Publication Activity Database

    Gies, D. R.; Bagmulo, W. G., Jr.; Baines, E. K.; ten Brummelaar, T.A.; Farrington, C.D.; Goldfinger, P.J.; Grundstrom, E.D.; Huang, W.; McAlister, H.A.; Mérand, A.; Sturmann, J.; Sturmann, L.; Touhami, Y.; Turner, N.H.; Wingert, D.W.; Berger, D.H.; McSwain, M.V.; Aufdenberg, J.P.; Ridgway, S.T.; Cochran, A.L.; Lester, D.F.; Sterling, N.C.; Bjorkman, J.E.; Bjorkman, K.S.; Koubský, Pavel

    2007-01-01

    Roč. 654, č. 1 (2007), s. 527-543 ISSN 0004-637X Institutional research plan: CEZ:AV0Z10030501 Keywords : CHARA * Be stars * interferometry disks Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 6.405, year: 2007

  7. Dynamic aspects of spermiogenic chromatin condensation patterning by phase separation during the histone-to-protamine transition in charalean algae and relation to bryophytes.

    Science.gov (United States)

    Kasinsky, H E; Ellis, S; Martens, G; Ausió, J

    2014-12-01

    During early-to-middle spermiogenesis in multicellular, internally fertilizing charalean green algae (Chara fibrosa, Chara vulgaris, Chara tomentosa, Nitella missouriensis), patterning of chromatin/nucleoplasm in developing spermatid nuclei changes from granules → fibers → contorted lamellae → condensed chromatin. Cytochemical, immunocytochemical, electrophoretic studies on C. vulgaris and C. tomentosa spermatids (Kwiatkowska, Poplonska) and amino acid analysis of protamines in Chara corallina sperm (Reynolds, Wolfe), indicate that more positively charged protamines replace histones directly during spermiogenesis, not indirectly through other intermediate transitional proteins as in internally fertilizing neogastropods and sharks with more ordered spermatid lamellae. We hypothesize that such lamellar-mediated patterning is due to liquid-liquid phase separation by spinodal decomposition. This is a spontaneous thermodynamic process that involves diffusive instability of a lamellar chromatin network, a dominant pattern repeat distance and bicontinuity of chromatin/nucleoplasm phases. C. vulgaris sperm show contorted lamellae in the posterior region, whereas C. corallina sperm display contorted peripheral lamellae and interior fibrils. Among internally fertilizing liverworts, which may have evolved from Zygnematales, mid-spermatid nuclei lack lamellae. Instead they display self-coiled chromatin rods in Blasia pusilla, contain short chromatin tubules in Haplomitrium hookeri resembling those in internally fertilizing mosses and a hornwort and indirectly replace histones with protamines in Marchantia polymorpha. Copyright © 2014. Published by Elsevier Ltd.

  8. Biological importance of marine algae.

    Science.gov (United States)

    El Gamal, Ali A

    2010-01-01

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

  9. THE CHARA ARRAY ANGULAR DIAMETER OF HR 8799 FAVORS PLANETARY MASSES FOR ITS IMAGED COMPANIONS

    International Nuclear Information System (INIS)

    Baines, Ellyn K.; White, Russel J.; Jones, Jeremy; Boyajian, Tabetha; McAlister, Harold A.; Ten Brummelaar, Theo A.; Turner, Nils H.; Sturmann, Judit; Sturmann, Laszlo; Goldfinger, P. J.; Farrington, Christopher D.; Riedel, Adric R.; Huber, Daniel; Ireland, Michael; Von Braun, Kaspar; Ridgway, Stephen T.

    2012-01-01

    HR 8799 is an hF0 mA5 γ Doradus-, λ Bootis-, Vega-type star best known for hosting four directly imaged candidate planetary companions. Using the CHARA Array interferometer, we measure HR 8799's limb-darkened angular diameter to be 0.342 ± 0.008 mas (an error of only 2%). By combining our measurement with the star's parallax and photometry from the literature, we greatly improve upon previous estimates of its fundamental parameters, including stellar radius (1.44 ± 0.06 R ☉ ), effective temperature (7193 ± 87 K, consistent with F0), luminosity (5.05 ± 0.29 L ☉ ), and the extent of the habitable zone (HZ; 1.62-3.32 AU). These improved stellar properties permit much more precise comparisons with stellar evolutionary models, from which a mass and age can be determined, once the metallicity of the star is known. Considering the observational properties of other λ Bootis stars and the indirect evidence for youth of HR 8799, we argue that the internal abundance, and what we refer to as the effective abundance, is most likely near solar. Finally, using the Yonsei-Yale evolutionary models with uniformly scaled solar-like abundances, we estimate HR 8799's mass and age considering two possibilities: 1.516 +0.038 –0.024 M ☉ and 33 +7 –13.2 Myr if the star is contracting toward the zero-age main sequence or 1.513 +0.023 –0.024 M ☉ and 90 +381 –50 Myr if it is expanding from it. This improved estimate of HR 8799's age with realistic uncertainties provides the best constraints to date on the masses of its orbiting companions, and strongly suggests they are indeed planets. They nevertheless all appear to orbit well outside the HZ of this young star.

  10. Genomics of Volvocine Algae

    Science.gov (United States)

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

    2015-01-01

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

  11. Re-modeling Chara action potential: II. The action potential form under salinity stress

    Directory of Open Access Journals (Sweden)

    Mary Jane Beilby

    2017-04-01

    Full Text Available In part I we established Thiel-Beilby model of the Chara action potential (AP. In part II the AP is investigated in detail at the time of saline stress. Even very short exposure of salt-sensitive Chara cells to artificial pond water with 50 mM NaCl (Saline APW modified the AP threshold and drastically altered the AP form. Detailed modeling of 14 saline APs from 3 cells established that both the Ca2+ pump and the Ca2+ channels on internal stores seem to be affected, with the changes sometimes cancelling and sometimes re-enforcing each other, leading to APs with long durations and very complex forms. The exposure to salinity offers further insights into AP mechanism and suggests future experiments. The prolonged APs lead to greater loss of chloride and potassium ions, compounding the effects of saline stress.

  12. Microanalytical identification of barium sulphate crystals in statoliths of Chara Rhizoids

    Science.gov (United States)

    Schroeter, K.; Lauchli, A.; Sievers, A. J.

    1979-01-01

    In contrast to higher plants, Chara rhizoids contain statolith vacuoles filled with biocrystallites of BaS04 in the form of rods composed of globular subunits ca. 7 nm in diameter. The revelation of the crystallites under electron microscopy is dependent on the fixative; best structural preservation was observed after fixation in a buffered glutaraldehyde + acrolein solution; 0s04 and KMnO4 partially dissolved both the biocrystallites and synthetic BaS04.

  13. [Moyse Charas, apothecary and medical doctor (Uzés 1619 - Paris 1698)].

    Science.gov (United States)

    Felix, Fred W

    2002-01-01

    Some new information, based on many unedited documents is presented, in order to complete the biography of Moyse Charas, as published in this revue by Dorveaux (1929) and Bouvet (1949). The origin of the protestant family Charas lies in Pont-Saint-Espirt, from where the parents of Moyse Charas, passing Uzés, moved to Orange, where he took up the profession of apothecary and was declared Master by Frederick Henry, prince of Orange. Later, in Paris, he had contacts with the Dutch diplomat Constantijn Huygens and his son, the scientist Christiaan Huygens, and with the English physician and philosopher John Locke. After shorter visits to London and the Royal Society he lived there for a certain time, being called to contribute to cure King Charles II. He revisited Orange to get his promotion as a doctor of medicine. After having practised for some time in Holland he went to Spain for five years, as a physician of the embassy of the States General in Madrid and later in Galice. The last six months he suffered imprisonment by the Inquisition. Liberated after his conversion to Catholicism, he could finally return to Paris.

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

    Science.gov (United States)

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

  15. Magnetic separation of algae

    Science.gov (United States)

    Nath, Pulak; Twary, Scott N.

    2016-04-26

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

  16. Algae-Based Carbon Sequestration

    Science.gov (United States)

    Haoyang, Cai

    2018-03-01

    Our civilization is facing a series of environmental problems, including global warming and climate change, which are caused by the accumulation of green house gases in the atmosphere. This article will briefly analyze the current global warming problem and propose a method that we apply algae cultivation to absorb carbon and use shellfish to sequestrate it. Despite the importance of decreasing CO2 emissions or developing carbon-free energy sources, carbon sequestration should be a key issue, since the amount of carbon dioxide that already exists in the atmosphere is great enough to cause global warming. Algae cultivation would be a good choice because they have high metabolism rates and provides shellfish with abundant food that contains carbon. Shellfish’s shells, which are difficult to be decomposed, are reliable storage of carbon, compared to dead organisms like trees and algae. The amount of carbon that can be sequestrated by shellfish is considerable. However, the sequestrating rate of algae and shellfish is not high enough to affect the global climate. Research on algae and shellfish cultivation, including gene technology that aims to create “super plants” and “super shellfish”, is decisive to the solution. Perhaps the baton of history will shift to gene technology, from nuclear physics that has lost appropriate international environment after the end of the Cold War. Gene technology is vital to human survival.

  17. [Modelling of pattern formation and oscillations in pH and transmembrane potential near the cell membrane of Chara corallina].

    Science.gov (United States)

    Pliusnina, T Iu; Lavrova, A I; Riznichenko, G Iu; Rubin, A B

    2005-01-01

    A mathematical model of potencial-dependent proton transfer across the membrane of Chara corallina cells is considered. To construct the model, partial differential equations describing the system dynamics in time and in space were used. The variables of the model are the proton concentration and membrane potential. The model describes the experimentally observed inhomogeneous distribution of transmembrane potential and pH along the membrane and oscillations of the potential and pH in time. A mechanism of the distribution of pH and membrane potential along the Chara corallina cell is suggested.

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

    Science.gov (United States)

    Applied Biochemists, Inc., Mequon, WI.

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

  19. Anion channels in chara corallina tonoplast membrane: calcium dependence and rectification.

    Science.gov (United States)

    Berecki, G; Varga, Z; Van Iren, F; Van Duijn, B

    1999-11-15

    Tonoplast K(+) channels of Chara corallina are well characterized but only a few reports mention anion channels, which are likely to play an important role in the tonoplast action potential and osmoregulation of this plant. For experiments internodal cells were isolated. Cytoplasmic droplets were formed in an iso-osmotic bath solution according to a modified procedure. Ion channels with conductances of 48 pS and 170 pS were detected by the patch-clamp technique. In the absence of K(+) in the bath solution the 170 pS channel was not observed at negative pipette potential values. When Cl(-) on either the vacuolar side or the cytoplasmic side was partly replaced with F(-), the reversal potential of the 48 pS channel shifted conform to the Cl(-) equilibrium potential with similar behavior in droplet-attached and excised patch mode. These results showed that the 48 pS channel was a Cl(-) channel. In droplet-attached mode the channel rectified outward current flow, and the slope conductance was smaller. When Chara droplets were formed in a bath solution containing low (10(-8) m) Ca(2+), then no Cl(-) channels could be detected either in droplet-attached or in inside-out patch mode. Channel activity was restored if Ca(2+) was applied to the cytoplasmic side of inside-out patches. Rectification properties in the inside-out patch configuration could be controlled by the holding pipette potential. Holding potential values negative or positive to the calculated reversal potential for Cl(-) ions induced opposite rectification properties. Our results show Ca(2+)-activated Cl(-) channels in the tonoplast of Chara with holding potential dependent rectification.

  20. Streptophyte algae and the origin of embryophytes.

    Science.gov (United States)

    Becker, Burkhard; Marin, Birger

    2009-05-01

    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. 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. 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

  1. Plasmodesmata of brown algae

    OpenAIRE

    Terauchi, Makoto; Nagasato, Chikako; Motomura, Taizo

    2014-01-01

    Plasmodesmata (PD) are intercellular connections in plants which play roles in various developmental processes. They are also found in brown algae, a group of eukaryotes possessing complex multicellularity, as well as green plants. Recently, we conducted an ultrastructural study of PD in several species of brown algae. PD in brown algae are commonly straight plasma membrane-lined channels with a diameter of 10?20?nm and they lack desmotubule in contrast to green plants. Moreover, branched PD ...

  2. Effect of avermectins on Ca2+-dependent Cl- currents in plasmalemma of Chara corallina cells.

    Science.gov (United States)

    Drinyaev, V A; Mosin, V A; Kruglyak, E B; Sterlina, T S; Kataev, A A; Berestovsky, G N; Kokoz, Y M

    2001-07-01

    A natural complex of avermectins, aversectin C, and a component of this complex, avermectin A1, were shown to change the conductivity of Ca2+-dependent Cl- channels of plasmalemma of Chara corallina cells by acting from the outer side of the cellular membrane. Low concentrations of aversectin C and avermectin A1 increased the Cl- current: K1/2 = 35 ng/ml for the whole complex and K1/2 = 21 pg/ml for A1. Relatively high concentrations of the compounds suppressed the Cl- current: K1/2 = 2.2 microg/ml for aversectin C and K1/2 = 4.2 ng/ml for A1. The Hill coefficient for the interaction of avermectin A1 with the corresponding targets was identical for stimulation and suppression of the Cl- current: 2.8 and 2.5, respectively. Bicuculline, a nonspecific inhibitor of the GABAa receptors, did not influence stimulation of Cl- currents caused by low concentrations of avermectins, but at the same time blocked suppression of the Cl- currents by high concentrations of avermectins. Avermectins A2, B1, B2, abamectin and 22,23-dihydroavermectin B1 (ivermectin) did not affect the Cl- currents of Chara corallina cells.

  3. Comparative study on photosynthetic activity of chloroplasts in acid and alkaline zones of Chara corallina.

    Science.gov (United States)

    Bulychev, A A; Cherkashin, A A; Rubin, A B; Vredenberg, W J; Zykov, V S; Müller, S C

    2001-03-01

    A novel experimental approach has been applied to investigate the relationship between pH banding in Chara cells and photosynthetic activity of chloroplasts located in cell regions adjacent to acid and alkaline bands. The combination of pH microelectrode technique with pulse amplitude modulation (PAM) microfluorimetry enabled parallel measurements of longitudinal pH profiles and chlorophyll fluorescence yield in acid and alkaline zones of individual Chara cells. The scanning with a pH-microelectrode along the cell length revealed the light-dependent pH pattern, i.e., alternating acid and alkaline bands with pH differences as large as 2 - 3 pH units. In parallel, measurements of chlorophyll fluorescence yield under actinic light were performed using PAM microfluorometry. It was found that the effective photochemical yield of photosystem II is substantially higher in acid than in alkaline zones. The results clearly show that the banding pattern is not confined solely to the plasmalemma but is also exhibited in alternating photosynthetic performance of the underlying chloroplast layer. Apparently, the acid regions enriched with CO2 ensure sufficient flow of this substrate to the Calvin cycle reactions, thus promoting the photosynthetic rate, whereas the alkaline zones devoid of CO2 favor radiative losses of absorbed solar energy in chloroplasts.

  4. FT-IR study of the Chara corallina cell wall under deformation.

    Science.gov (United States)

    Toole, Geraldine A; Kacuráková, Marta; Smith, Andrew C; Waldron, Keith W; Wilson, Reginald H

    2004-02-25

    Fourier-transform infrared (FT-IR) microspectroscopy was used to investigate both the chemical composition of, and the effects of an applied strain on, the structure of the Chara corallina cell wall. The inner layers of the cell wall are known to have a transverse cellulose orientation with a gradient through the thickness to longitudinal orientation in the older layers. In both the native state and following the removal of various biopolymers by a sequential extraction infrared dichroism was used to examine the orientation of different biopolymers in cell-wall samples subjected to longitudinal strain. In the Chara system, cellulose microfibrils were found to be aligned predominantly transverse to the long axis of the cell and became orientated increasingly transversely as longitudinal strain increased. Simultaneously, the pectic polysaccharide matrix underwent molecular orientation parallel to the direction of strain. Following extraction in CDTA, microfibrils were orientated transversely to the strain direction, and again the degree of transverse orientation increased with increasing strain. However, the pectic polysaccharides of the matrix were not detected in the dichroic difference spectra. After a full sequential extraction, the cellulose microfibrils, now with greatly reduced crystallinity, were detected in a longitudinal direction and they became orientated increasingly parallel to the direction of strain as it increased.

  5. Identifying cytoplasmic input to the cell wall of growing Chara corallina.

    Science.gov (United States)

    Proseus, Timothy E; Boyer, John S

    2006-01-01

    Plants enlarge mostly because the walls of certain cells enlarge, with accompanying input of wall constituents and other factors from the cytoplasm. However, the enlargement can occur without input, suggesting an uncertain relationship between cytoplasmic input and plant growth. Therefore, the role of the input was investigated by quantitatively comparing growth in isolated walls (no input) with that in living cells (input occurring). Cell walls were isolated from growing internodes of Chara corallina and filled with pressurized oil to control turgor pressure while elongation was monitored. Turgor pressure in living cells was similarly controlled and monitored by adding/removing cell solution. Temperature was varied in some experiments. At all pressures and temperatures, isolated walls displayed turgor-driven growth indistinguishable in every respect from that in living cells, except the rate decelerated in the isolated walls while the living cells grew rapidly. The growth in the isolated walls was highly responsive to temperature, in contrast to the elastic extension that has been shown to be insensitive to similar temperatures. Consequently, strong intermolecular bonds were responsible for growth and weak bonds for elastic extension. Boiling the walls gave the same results, indicating that enzyme activities were not controlling these bonds. However, pectin added to isolated walls reversed their growth deceleration and returned the rate to that in the living cells. The pectin was similar to that normally produced by the cytoplasm and deposited in the wall, suggesting that continued cytoplasmic input of pectin may play a role in sustaining turgor-driven growth in Chara.

  6. [Effect of avermectns on Ca(2+)-dependent chloride currents in plasmalemma of Chara corallina cells].

    Science.gov (United States)

    Driniaev, V A; Mosin, V A; Krugliak, E B; Sterlina, T S; Viktorov, A V; Kataev, A A; Berestovskiĭ, G N; Kataev, T S; Kokoz, Iu M

    2001-01-01

    A natural complex of avermectins, aversectin C, and a component of this complex, avermectin A1, were shown to change the conductivity of Ca(2+)-dependent chloride channels of plasmalemma of Chara corallina cells by acting only from the outer side of the cellular membrane. Low concentrations of aversectin C and avermectin A1 increased the chloride current: K1/2 = 3.5 x 10(-5) mg/ml for the whole complex and K1/2 = 2.1 x 10(-3) mg/ml for A1. Relatively high concentrations of the compounds suppressed the chloride current: K1/2 = 2.2 x 10(-3) mg/ml for aversectin C and K1/2 = 4.2 x 10(-6) mg/ml for A1. The Hill coefficients for the interaction of avermectin A1 with the corresponding targets for stimulation and suppression of the chloride current were 2.8 and 2.5 respectively. Bicuculine, a non-specific inhibitor of the GABA alpha-receptors, did not influence stimulation of chloride currents caused by action of low concentrations of avermectins, but at the same time blocked suppression of the chloride currents associated with the action of high doses of avermectins. Avermectins A2, B1 (abamectin), B2 and 22,23-dihydroavermectin B1 (vermectin) in the concentration range studied, did not affect the chloride currents of Chara corallina cells.

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

    Energy Technology Data Exchange (ETDEWEB)

    Gharagozloo, Patricia E.; Drewry, Jessica Louise.

    2013-01-01

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

  8. [Harmful algae and health].

    Science.gov (United States)

    Kankaanpää, Harri T

    2011-01-01

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

  9. Method and apparatus for processing algae

    Science.gov (United States)

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

    2012-07-03

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

  10. Algae Derived Biofuel

    Energy Technology Data Exchange (ETDEWEB)

    Jahan, Kauser [Rowan Univ., Glassboro, NJ (United States)

    2015-03-31

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

  11. Induction of a new alkaline band at a target position in internodal cells of Chara corallina.

    Science.gov (United States)

    Shimmen, Teruo; Yamamoto, Ako

    2002-09-01

    Characean cells develop alternating alkaline and acid bands on their surface upon illumination. However, the mechanism of band formation is not fully understood. In the present study, we succeeded in inducing a new alkaline band at an original acid band in internodal cells of Chara corallina. Chloroplasts in an acid band were locally removed by wounding the cell in the absence of the cell turgor pressure. The chloroplast-removed area was observed as a white belt in a green cylindrical internodal cell. This internodal cell developed a new alkaline band on the surface at the chloroplast-removed area. The narrower the chloroplast-removed area, the less significant the extent of OH(-) extrusion. This is the first success in inducing a new alkaline band at a target position in Characeae.

  12. Electrophysiological characterization of the node in Chara corallina: functional differentiation for wounding response.

    Science.gov (United States)

    Shimmen, Teruo

    2008-02-01

    Electrical characteristics of the node were analyzed in comparison with those of the flank of the internodal cell in Chara corallina. The dependence of the membrane potential of the node on pH and K+ concentration was almost the same as that of the flank. In the flank, the increase in the Ca2+ concentration stopped the depolarization in the presence of 100 mM KCl. In the node, however, Ca2+ could not stop the depolarization induced by 100 mM KCl. It has been reported that the node has a function to tranduce the signal of osmotic shock into a transient depolarization. In combination with osmotic shock, 10 mM K+ could induce a long-lasting depolarization of the node. These electrical characteristics of the node were suggested to be responsible for the electrical response to wounding in Characeae.

  13. Transduction of pressure signal to electrical signal upon sudden increase in turgor pressure in Chara corallina.

    Science.gov (United States)

    Shimmen, Teruo; Ogata, Koreaki

    2013-05-01

    By taking advantage of large cell size of Chara corallina, we analyzed the membrane depolarization induced by decreased turgor pressure (Shimmen in J Plant Res 124:639-644, 2011). In the present study, the response to increased turgor pressure was analyzed. When internodes were incubated in media containing 200 mM dimethyl sulfoxide, their intracellular osmolality gradually increased and reached a steady level after about 3 h. Upon removal of dimethyl sulfoxide, turgor pressure quickly increased. In response to the increase in turgor pressure, the internodes generated a transient membrane depolarization at its nodal end. The refractory period was very long and it took about 2 h for full recovery after the depolarizing response. Involvement of protein synthesis in recovery from refractoriness was suggested, based on experiments using inhibitors.

  14. Periplasm turgor pressure controls wall deposition and assembly in growing Chara corallina cells.

    Science.gov (United States)

    Proseus, Timothy E; Boyer, John S

    2006-07-01

    New wall deposition usually accompanies plant growth. External osmotica inhibit both processes but wall precursors continue to be synthesized, and exocytosis follows. Consequently, the osmotica appear to act outside of the plasma membrane. Because this implies an action of turgor pressure (P) on the periplasm by unknown mechanisms, the following study was undertaken to determine whether P could act in a way that altered wall deposition and assembly in the periplasm while the cells grow. Cells of Chara corallina were exposed to P slightly below normal by using a pressure probe while supplying inorganic carbon in light. After labelling, the walls were isolated and the amount of new wall was determined. Similar measurements were made after treatment with osmotica. Chlortetracycline-stimulated exocytosis was determined microscopically. Polysaccharide properties were determined by confocal microscopy and vapour pressure osmometry in an 'artificial periplasm' in isolated Chara cell walls, using labelled dextran as an analogue of hemicellulose, and polygalacturonate as pectin. Rapid growth and wall deposition occurred at normal P of 0.5 MPa but both processes decreased when P was lowered 0.1 MPa. Inorganic carbon uptake and exocytosis were unaffected. In the artificial periplasm, normal P caused high polysaccharide concentrations and rapid polysaccharide entry into the wall, and gel formation in the pectin. Lowering P decreased entry and gel formation. This is the first indication that normal P of 0.5 MPa can concentrate periplasmic polysaccharides sufficiently to cause cross-linking and gel formation in pectins while simultaneously fostering the entry of large polysaccharides into small interstices in the existing wall. This P-action would thicken the primary wall and form a smooth transition between the new and old structure, suggesting a molecular mechanism of wall deposition and assembly while the wall extends.

  15. Algae: putting carbon dioxide in a bind

    Energy Technology Data Exchange (ETDEWEB)

    Ewers, J.; Wiechers, G. [RWE Power (Germany)

    2009-03-15

    German utility RWE Power has initiated a cutting edge project that is investigating the use of marine microalgae to capture carbon dioxide produced during lignite combustion. At its Niederaussem power plant, a pilot plant has been erected for the production of microalgae. Flue gas is withdrawn from the lignite-based power plant and transported through polyethylene pipes to the microalgae production plant. The CO{sub 2} in the flue gas is dissolved in the algae suspension and adsorbed by the algae for growth in photobioreactors, developed by Noragreen Projektmanagement GmbH. The photobioreactors which consist of clear plastic hoses, fixed in V shape to supports. The study is aiming to optimise the entire algae production process and subsequent conversion and use of the algae biomass produced. Uses being investigated include hydrothermal carbonization to obtain hydrocarbon products. 1 figs., 1 photo.

  16. Blue-Green Algae

    Science.gov (United States)

    ... people with hepatitis C or hepatitis B. HIV/AIDS. Research on the effects of blue-green algae in people with HIV/AIDS has been inconsistent. Some early research shows that taking 5 grams of blue-green ...

  17. Biofuels and algae

    International Nuclear Information System (INIS)

    Anon.

    2011-01-01

    Bio-fuels based on micro-algae are promising, their licensing for being used in plane fuels in a mix containing 50% of fossil kerosene is expected in the coming months. In United-States research on bio-fuels has been made more important since 2006 when 2 policies were launched: 'Advanced energy initiative' and 'Twenty-in-ten', the latter aiming to develop alternative fuels. In Europe less investment has been made concerning micro-algae fuels but research programs were launched in Spain, United-Kingdom and France. In France 3 important projects were launched: SHAMASH (2006-2010) whose aim is to produce lipidic fuels from micro-algae, ALGOHUB (2008-2013) whose aim is to use micro-algae as a raw material for humane and animal food, medicine and cosmetics, SYMBIOSE (2009-2011) whose aim is the optimization of the production of methane through the anaerobic digestion of micro-algae, SALINALGUE (2010-2016) whose aim is to grow micro-algae for the production of bio-energies and bio-products. (A.C.)

  18. Heterotrimeric G proteins in green algae: an early innovation in the evolution of the plant lineage.

    Science.gov (United States)

    Hackenberg, Dieter; Pandey, Sona

    2014-01-01

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

  19. The defense substance allicin from garlic permeabilizes membranes of Beta vulgaris, Rhoeo discolor, Chara corallina and artificial lipid bilayers.

    Science.gov (United States)

    Gruhlke, Martin C H; Hemmis, Birgit; Noll, Ulrike; Wagner, Richard; Lühring, Hinrich; Slusarenko, Alan J

    2015-04-01

    Allicin (diallylthiosulfinate) is the major volatile- and antimicrobial substance produced by garlic cells upon wounding. We tested the hypothesis that allicin affects membrane function and investigated 1) betanine pigment leakage from beetroot (Beta vulgaris) tissue, 2) the semipermeability of the vacuolar membrane of Rhoeo discolor cells, 3) the electrophysiology of plasmalemma and tonoplast of Chara corallina and 4) electrical conductivity of artificial lipid bilayers. Garlic juice and chemically synthesized allicin were used and betanine loss into the medium was monitored spectrophotometrically. Rhoeo cells were studied microscopically and Chara- and artificial membranes were patch clamped. Beet cell membranes were approximately 200-fold more sensitive to allicin on a mol-for-mol basis than to dimethyl sulfoxide (DMSO) and approximately 400-fold more sensitive to allicin than to ethanol. Allicin-treated Rhoeo discolor cells lost the ability to plasmolyse in an osmoticum, confirming that their membranes had lost semipermeability after allicin treatment. Furthermore, allicin and garlic juice diluted in artificial pond water caused an immediate strong depolarization, and a decrease in membrane resistance at the plasmalemma of Chara, and caused pore formation in the tonoplast and artificial lipid bilayers. Allicin increases the permeability of membranes. Since garlic is a common foodstuff the physiological effects of its constituents are important. Allicin's ability to permeabilize cell membranes may contribute to its antimicrobial activity independently of its activity as a thiol reagent. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Antioxidant Activity of Hawaiian Marine Algae

    Directory of Open Access Journals (Sweden)

    Anthony D. Wright

    2012-02-01

    Full Text Available 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.

  1. Antioxidant activity of Hawaiian marine algae.

    Science.gov (United States)

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

    2012-02-01

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

  2. Fluorescence Properties of Chlorella sp. Algae

    Directory of Open Access Journals (Sweden)

    Tibor Teplicky

    2017-01-01

    Full Text Available Water quality and its fast and reliable monitoring is the challenge of the future. Design of appropriate biosensors that would be capable of non-invasive identification of water pollution is an important prerequisite for such challenge. Chlorophylls are pigments, naturally presented in all plants that absorb light. The main forms of chlorophyll in algae are chlorophyll a and chlorophyll b, other pigments include xantophylls and beta-carotenes. Our aim was to characterize endogenous fluorescence of the Chlorella sp. algae, present naturally in drinking water. We recorded spatial, spectral and lifetime fluorescence distribution in the native algae. We noted that the fluorescence was evenly distributed in the algae cytosol, but lacked in the nucleus and reached maximum at 680-690 nm. Fluorescence decay of chlorella sp. was double-exponential, and clearly shorter than that of its isolated pigments. For the first time, fluorescence lifetime image of the algae is presented. Study of the fluorescence properties of algae is aimed at the improvement of water supply contamination detection and cleaning.

  3. Parasites in algae mass culture

    Directory of Open Access Journals (Sweden)

    Todd William Lane

    2014-06-01

    Full Text Available 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.

  4. Antimicrobial Activity of Extracts from Six Green Algae from Tanzania

    OpenAIRE

    Mtolera, M.S.P.; Semesi, A.

    1996-01-01

    Many algae species have been shown to have bactericidal or bacteriostatic substances (Glombitza, I979;Michaneck, 1979; Caccamese et al., 1980; Fenical & Paul, 1984; Niang& Hung, 1984). The antibacterialagents found in the algae include amino acids, terpenoids, phlorotannins, acrylic acid, phenoliccompounds, steroids, halogenated ketones and alkanes, cyclic polysulphides and fatty acids. In a large numberof marine algae antimicrobial activities are attributed to the presence of acrylic acid.

  5. Anticoagulant effect of marine algae.

    Science.gov (United States)

    Kim, Se-Kwon; Wijesekara, Isuru

    2011-01-01

    Recently, a great deal of interest has been developed in the nutraceutical and pharmaceutical industries to isolate natural anticoagulant compounds from marine resources. Among marine resources, marine algae are valuable sources of novel bioactive compounds with anticoagulant effect. Phlorotannins and sulfated polysaccharides such as fucoidans in brown algae, carrageenans in red algae, and ulvans in green algae have been recognized as potential anticoagulant agents. Therefore, marine algae-derived phlorotannins and SPs have great potential for developing as anticoagulant drugs in nutraceutical and pharmaceutical areas. This chapter focuses on the potential anticoagulant agents in marine algae and presents an overview of their anticoagulant effect. Copyright © 2011 Elsevier Inc. All rights reserved.

  6. Plasmodesmata of brown algae.

    Science.gov (United States)

    Terauchi, Makoto; Nagasato, Chikako; Motomura, Taizo

    2015-01-01

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

  7. Control of Cl- efflux in chara corallina by cytosolic pH, free ca2+, and phosphorylation indicates a role of plasma membrane anion channels in cytosolic pH regulation

    Science.gov (United States)

    Johannes; Crofts; Sanders

    1998-09-01

    Enhanced Cl- efflux during acidosis in plants is thought to play a role in cytosolic pH (pHc) homeostasis by short-circuiting the current produced by the electrogenic H+ pump, thereby facilitating enhanced H+ efflux from the cytosol. Using an intracellular perfusion technique, which enables experimental control of medium composition at the cytosolic surface of the plasma membrane of charophyte algae (Chara corallina), we show that lowered pHc activates Cl- efflux via two mechanisms. The first is a direct effect of pHc on Cl- efflux; the second mechanism comprises a pHc-induced increase in affinity for cytosolic free Ca2+ ([Ca2+]c), which also activates Cl- efflux. Cl- efflux was controlled by phosphorylation/dephosphorylation events, which override the responses to both pHc and [Ca2+]c. Whereas phosphorylation (perfusion with the catalytic subunit of protein kinase A in the presence of ATP) resulted in a complete inhibition of Cl- efflux, dephosphorylation (perfusion with alkaline phosphatase) arrested Cl- efflux at 60% of the maximal level in a manner that was both pHc and [Ca2+]c independent. These findings imply that plasma membrane anion channels play a central role in pHc regulation in plants, in addition to their established roles in turgor/volume regulation and signal transduction.

  8. A Characeae Cells Plasma Membrane as a Model for Selection of Bioactive Compounds and Drugs: Interaction of HAMLET-Like Complexes with Ion Channels of Chara corallina Cells Plasmalemma.

    Science.gov (United States)

    Kataev, Anatoly; Zherelova, Olga; Grishchenko, Valery

    2016-12-01

    Interaction of a HAMLET-like La-OA cytotoxic complex (human α-lactalbumin-oleic acid) and its constituents with the excitable plasmalemma of giant Chara corallina cells was investigated. The voltage-clamp technique was used to study Ca 2+ and Cl - transient currents in the plasmalemma of intact cells. The action of the complex and OA on the target cell membrane has a dose-dependent character. It was found that the La-OA complex has an inhibiting effect on Ca 2+ current across the plasmalemma, while α-lactalbumin alone does not affect the electrophysiological characteristics of the cellular membrane. However, oleic acid blocks Ca 2+ current across the plasmalemma. This is accompanied by the induction of a non-selective conductivity in the cellular membrane, a decrease in the resting potential and plasma membrane resistance of algal cells. We propose that the cytotoxicity of La-OA and other HAMLET-like complexes is determined by oleic acid acting as a blocker of potential-dependent Ca 2+ channels in the plasma membrane of target cells. The presented results show that the study model of green algae C. corallina cells plasmalemma is a convenient tool for the investigation of ion channels in many animal cells.

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

    Science.gov (United States)

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

    2013-01-01

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

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

    Science.gov (United States)

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

    2012-11-06

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

  11. Recombinant motor domain constructs of Chara corallina myosin display fast motility and high ATPase activity.

    Science.gov (United States)

    Ito, Kohji; Kashiyama, Taku; Shimada, Kiyo; Yamaguchi, Akira; Awata, Jun ya; Hachikubo, You; Manstein, Dietmar J; Yamamoto, Keiichi

    2003-12-26

    The mechanism and structural features that are responsible for the fast motility of Chara corallina myosin (CCM) have not been elucidated, so far. The low yields of native CCM that can be purified to homogeneity were the major reason for this. Here, we describe the expression of recombinant CCM motor domains, which support the fast movement of actin filaments in an in vitro motility assay. A CCM motor domain without light chain binding site moved actin filaments at a velocity of 8.8 microm/s at 30 degrees C and a CCM motor domain with an artificial lever arm consisting of two alpha-actinin repeats moved actin filaments at 16.2 microm/s. Both constructs displayed high actin-activated ATPase activities ( approximately 500 Pi/s/head), which is indicative of a very fast hydrolysis step. Our results provide an excellent system to dissect the specific structural and functional features that distinguish the myosin responsible for fast cytoplasmic streaming.

  12. Regulation of the H+ pump activity in the plasma membrane of internally perfused Chara corallina.

    Science.gov (United States)

    Tsutsui, I; Ohkawa, T

    2001-05-01

    The role of cytoplasm for the maintenance of the H+ pump activity in Chara corallina internodal cells was examined by the intracellular perfusion technique. Cytoplasm-rich and -poor states were obtained by changing the perfusion time, short-term (less than 2 min) and long-term (more than 5 min), respectively. A large portion of cytoplasm was left by short-term perfusion but most of the cytoplasm was removed by long-term perfusion. The activities of the H+ pump of these two different conditions were examined by measuring current-voltage relation (I-V curve) and conductance-voltage relation (G-V curve) under voltage clamp conditions. The H+ pump conductance decreased to 37%, 9% and zero by short-term, long-term and hexokinase perfusion, respectively, whereas the passive channel conductance decreased to 71%, 39% and 73% by short-term, long-term and hexokinase perfusion, respectively. On the other hand, the electromotive-force of the H+ pump (approximately -260 mV) and the passive channel (approximately -130 mV) were not affected by either short- or long-term perfusion. It is indicated that the cytoplasm plays an essential role to regulate the activity of both the H+ pump and the passive channel together with ATP.

  13. Characterization of the Red Giant HR 2582 Using the CHARA Array

    Science.gov (United States)

    Baines, Ellyn K.; McAlister, Harold A.; ten Brummelaar, Theo A.; Turner, Nils H.; Sturmann, Judit; Sturmann, Laszlo; Farrington, Christopher D.; Vargas, Norm; van Belle, Gerard T.; Ridgway, Stephen T.

    2013-07-01

    We present the fundamental parameters of HR 2582, a high-mass red giant star whose evolutionary state is a mystery. We used the CHARA Array interferometer to directly measure the star's limb-darkened angular diameter (1.006 ± 0.020 mas) and combined our measurement with parallax and photometry from the literature to calculate its physical radius (35.76 ± 5.31 R ⊙), luminosity (517.8 ± 17.5 L ⊙), bolometric flux (14.8 ± 0.5 × 10-8 erg s-1 cm-2), and effective temperature (4577 ± 60 K). We then determined the star's mass (5.6 ± 1.7 M ⊙) using our new values with stellar oscillation results from Baudin et al. Finally, using the Yonsei-Yale evolutionary models, we estimated HR 2582's age to be 165^{+20}_{-15} Myr. While our measurements do not provide the precision required to definitively state where the star is in its evolution, it remains an excellent test case for evaluating stellar interior models.

  14. TAXONOMIC REEXAMINATION OF CHARA GLOBULARIS (CHARALES, CHAROPHYCEAE) FROM JAPAN BASED ON OOSPORE MORPHOLOGY AND rbcL GENE SEQUENCES, AND THE DESCRIPTION OF C. LEPTOSPORA SP. NOV.(1).

    Science.gov (United States)

    Sakayama, Hidetoshi; Kasai, Fumie; Nozaki, Hisayoshi; Watanabe, Makoto M; Kawachi, Masanobu; Shigyo, Mikao; Nishihiro, Jun; Washitani, Izumi; Krienitz, Lothar; Ito, And Motomi

    2009-08-01

    Chara globularis Thuillier (=f. globularis sensu R. D. Wood) is a widespread species of the genus and inhabits fresh- and brackish-water environments. In an attempt to reexamine the taxonomic status of C. globularis collected from Japan, we reassessed vegetative and oospore morphology of Japanese material and herbarium specimens originating from Europe (including the type specimen) and conducted molecular phylogenetic analyses based on rbcL gene sequences. Although the other vegetative morphologies were consistent with the description of C. globularis f. globularis sensu R. D. Wood, we identified two types of branchlets within the Japanese materials: one has elongate end segments (EL type), and the other has short end segments (SH type) corresponding to the type material. Moreover, the oospore wall of the EL type was different from that in the SH type. The oospores of the EL type were dark brown to reddish brown and had a spongy pattern with the pusticular elevations on the fossa wall, whereas the fossa wall of the SH type was black with a granulate to papillate or fine pusticular pattern. In addition, our sequence data demonstrated that these two types are separated phylogenetically from each other. Therefore, we describe the EL type as a new species, C. leptospora sp. nov. © 2009 Phycological Society of America.

  15. Modeling and optimization of algae growth

    OpenAIRE

    Thornton, Anthony Richard; Weinhart, Thomas; Bokhove, Onno; Zhang, Bowen; van der Sar, Dick M.; Kumar, Kundan; Pisarenco, Maxim; Rudnaya, Maria; Savceno, Valeriu; Rademacher, Jens; Zijlstra, Julia; Szabelska, Alicja; Zyprych, Joanna; van der Schans, Martin; Timperio, Vincent

    2010-01-01

    The wastewater from greenhouses has a high amount of mineral contamination and an environmentally-friendly method of removal is to use algae to clean this runo water. The algae consume the minerals as part of their growth process. In addition to cleaning the water, the created algal bio-mass has a variety of applications including production of bio-diesel, animal feed, products for pharmaceutical and cosmetic purposes, or it can even be used as a source of heating or electricity. The aim of t...

  16. Modeling and optimization of algae growth

    OpenAIRE

    Thornton, A; Weinhart, T; Bokhove, O; Zhang, B; Sar, van der, DM; Kumar, K Kundan; Pisarenco, M Maxim; Rudnaya, M Maria; Savcenco, V Valeriu; Rademacher, JDM; Zijlstra, J; Szabelska, A; Zyprych, J; Schans, van der, M Martin; Timperio, V

    2010-01-01

    The wastewater from greenhouses has a high amount of mineral contamination and an environmentally-friendly method of removal is to use algae to clean this runoff water. The algae consume the minerals as part of their growth process. In addition to cleaning the water, the created algal bio-mass has a variety of applications including production of bio-diesel, animal feed, products for pharmaceutical and cosmetic purposes, or it can even be used as a source of heating or electricity . The aim o...

  17. Fundamental properties of stars using asteroseismology from Kepler and CoRoT and interferometry from the CHARA Array

    DEFF Research Database (Denmark)

    Huber, D.; Ireland, M.J.; Bedding, T.R.

    2012-01-01

    We present results of a long-baseline interferometry campaign using the PAVO beam combiner at the CHARA Array to measure the angular sizes of five main-sequence stars, one subgiant and four red giant stars for which solar-like oscillations have been detected by either Kepler or CoRoT. By combining...... interferometric angular diameters, Hipparcos parallaxes, asteroseismic densities, bolometric fluxes, and high-resolution spectroscopy, we derive a full set of near-model-independent fundamental properties for the sample. We first use these properties to test asteroseismic scaling relations for the frequency...

  18. Bromophenols in Marine Algae and Their Bioactivities

    DEFF Research Database (Denmark)

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

    2011-01-01

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

  19. Turgor pressure moves polysaccharides into growing cell walls of Chara corallina.

    Science.gov (United States)

    Proseus, Timothy E; Boyer, John S

    2005-05-01

    Plant growth involves pressure-driven cell enlargement generally accompanied by deposition of new cell wall. New polysaccharides are secreted by the plasma membrane but their subsequent entry into the wall is obscure. Therefore, polysaccharides and gold colloids of various sizes were presented to the inner wall face as though they were secreted by the plasma membrane. Primary cell walls were isolated from growing internodes of Chara corallina and one end was attached to a glass capillary. Solutions of dextran or suspensions of gold colloids were pushed into the lumen by oil in the capillary. The oil did not enter the wall, and the solution or suspension was pressed against the inner wall face, pressurized at various 'artificial' P (turgor pressure), and polymer or colloid movement through the wall was monitored. Interstices in the wall matrix had a diameter of about 4.6 nm measured at high P with gold colloids. Small solute (0.8 nm) readily moved through these interstices unaffected by P. Dextrans of 3.5 nm diameter moved faster at higher P while dextran of 9 nm scarcely entered unless high P was present. Dextran of 11 nm did not enter unless P was above a threshold, and dextran of 27 nm did not enter at P as high as 0.5 MPa. The walls filtered the dextrans, which became concentrated against the inner wall face, and most polymer movement occurred after P stabilized and bulk flow ended. P created a steep gradient in concentration and mechanical force at the inner wall face that moved large polymers into small wall openings apparently by starting a polymer end or deforming the polymer mechanically at the inner wall face. This movement occurred at P generally accepted to extend the walls for growth.

  20. Direct measurement of aluminum uptake and distribution in single cells of Chara corallina.

    Science.gov (United States)

    Taylor, G J; McDonald-Stephens, J L; Hunter, D B; Bertsch, P M; Elmore, D; Rengel, Z; Reid, R J

    2000-07-01

    Quantitative information on the uptake and distribution of Al at the cellular level is required to understand mechanisms of Al toxicity, but direct measurement of uptake across the plasma membrane has remained elusive. We measured rates of Al transport across membranes in single cells of Chara corallina using the rare (26)Al isotope, an emerging technology (accelerator mass spectrometry), and a surgical technique for isolating subcellular compartments. Accumulation of Al in the cell wall dominated total uptake (71-318 microgram m(-2) min(-1)), although transport across the plasma membrane was detectable (71-540 ng m(-2) min(-1)) within 30 min of exposure. Transport across the tonoplast was initially negligible, but accelerated to rates approximating uptake across the plasma membrane. The avacuolate protoplasm showed signs of saturation after 60 min, but continued movement across the plasma membrane was supported by sequestration in the vacuole. Saturation of all compartments was observed after 12 to 24 h. Accumulation of Al in the cell wall reflected variation in [Al(3+)] induced by changes in Al supply or complexing ligands, but was unaffected by pH. In contrast, transport across the plasma membrane peaked at pH 4.3 and increased when [Al(3+)] was reduced by complexing ligands. Cold temperature (4 degrees C) reduced accumulation in the cell wall and protoplasm, whereas 2,4-dinitrophenol and m-chlorocarbonylcyanidephenyl hydrazone increased membrane transport by 12- to 13-fold. Our data suggest that the cell wall is the major site of Al accumulation. Nonetheless, membrane transport occurs within minutes of exposure and is supported by subsequent sequestration in the vacuole. The rapid delivery of Al to the protoplasm suggests that intracellular lesions may be possible.

  1. Transcriptomics in brown algae

    OpenAIRE

    Heinrich, Sandra

    2015-01-01

    Brown algae are distributed worldwide on rocky shores. They are importenet components of ecosystems, they provide habitat, shelter and serve as nurseries for various marine organisms. The geographic as well as depth distribution of macroalgae is constrained by abiotic factors, especially light and temperature. It is therefore likely that due to the global change, distribution patterns of these organisms will change. In this work the molecular acclimation of two prominent brown macroalgae, Sac...

  2. Heterotrimeric G-proteins in green algae. An early innovation in the evolution of the plant lineage.

    Science.gov (United States)

    Hackenberg, Dieter; Pandey, Sona

    2014-01-01

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

  3. Recent Advances in Marine Algae Polysaccharides: Isolation, Structure, and Activities.

    Science.gov (United States)

    Xu, Shu-Ying; Huang, Xuesong; Cheong, Kit-Leong

    2017-12-13

    Marine algae have attracted a great deal of interest as excellent sources of nutrients. Polysaccharides are the main components in marine algae, hence a great deal of attention has been directed at isolation and characterization of marine algae polysaccharides because of their numerous health benefits. In this review, extraction and purification approaches and chemico-physical properties of marine algae polysaccharides (MAPs) are summarized. The biological activities, which include immunomodulatory, antitumor, antiviral, antioxidant, and hypolipidemic, are also discussed. Additionally, structure-function relationships are analyzed and summarized. MAPs' biological activities are closely correlated with their monosaccharide composition, molecular weights, linkage types, and chain conformation. In order to promote further exploitation and utilization of polysaccharides from marine algae for functional food and pharmaceutical areas, high efficiency, and low-cost polysaccharide extraction and purification methods, quality control, structure-function activity relationships, and specific mechanisms of MAPs activation need to be extensively investigated.

  4. Washington State University Algae Biofuels Research

    Energy Technology Data Exchange (ETDEWEB)

    chen, Shulin [Washington State Univ., Pullman, WA (United States). Dept. of Biological Systems Engineering; McCormick, Margaret [Targeted Growth, Inc., Seattle, WA (United States); Sutterlin, Rusty [Inventure Renewables, Inc., Gig Harbor, WA (United States)

    2012-12-29

    The goal of this project was to advance algal technologies for the production of biofuels and biochemicals by establishing the Washington State Algae Alliance, a collaboration partnership among two private companies (Targeted Growth, Inc. (TGI), Inventure Chemicals (Inventure) Inc (now Inventure Renewables Inc) and Washington State University (WSU). This project included three major components. The first one was strain development at TGI by genetically engineering cyanobacteria to yield high levels of lipid and other specialty chemicals. The second component was developing an algal culture system at WSU to produce algal biomass as biofuel feedstock year-round in the northern states of the United States. This system included two cultivation modes, the first one was a phototrophic process and the second a heterotrophic process. The phototrophic process would be used for algae production in open ponds during warm seasons; the heterotrophic process would be used in cold seasons so that year-round production of algal lipid would be possible. In warm seasons the heterotrophic process would also produce algal seeds to be used in the phototrophic culture process. Selected strains of green algae and cyanobacteria developed by TGI were tested in the system. The third component was downstream algal biomass processing by Inventure that included efficiently harvesting the usable fuel fractions from the algae mass and effectively isolating and separating the usable components into specific fractions, and converting isolated fractions into green chemicals.

  5. Organophosphorous pesticides and estrogen induce transformation of breast cells affecting p53 and c-Ha-ras genes.

    Science.gov (United States)

    Calaf, Gloria M; Echiburu-Chau, Carlos; Roy, Debasish

    2009-11-01

    Cancer progression has been associated with an increase in genomic instability indicated by inactivation of tumor suppressor genes and activation of oncogenes. Epidemiological and experimental evidence has implicated estrogens in the etiology of breast cancer. To study environmental organophosphorous pesticides is of interest since evidence indicate that pesticides may enhance cell division, increasing the risk of breast cancer. The aim was to evaluate the effects of these pesticides, such as parathion and malathion in the presence of estrogen on malignant transformation as well as on genomic instability, that is in the frequency of loss of heterozygosity (LOH) and microsatellite instability (MSI). The MCF-10F immortalized human breast epithelial cell line, that was treated with parathion or malathion alone and in combination with estrogen was used. These studies indicated that either pesticide alone or in combination with estrogen induced malignant transformation as shown by anchorage-independent growth capability and invasive characteristics in comparison to control. Such malignant phenotypic characteristics were corroborated by significant (Pmutations in c-Ha-ras for codons 12 and 61. LOH was observed in codon 12 in the presence of estrogen or malathion alone. Parathion alone and combined with estrogen induced MSI in codon 61. It can be concluded that the organophosphorous pesticides parathion and malathion induced malignant transformation of breast cells through genomic instability altering p53 and c-Ha-ras, considered pivotal to cancer process.

  6. Accurate effective temperatures of the metal-poor benchmark stars HD 140283, HD 122563, and HD 103095 from CHARA interferometry

    Science.gov (United States)

    Karovicova, I.; White, T. R.; Nordlander, T.; Lind, K.; Casagrande, L.; Ireland, M. J.; Huber, D.; Creevey, O.; Mourard, D.; Schaefer, G. H.; Gilmore, G.; Chiavassa, A.; Wittkowski, M.; Jofré, P.; Heiter, U.; Thévenin, F.; Asplund, M.

    2018-03-01

    Large stellar surveys of the Milky Way require validation with reference to a set of `benchmark' stars whose fundamental properties are well determined. For metal-poor benchmark stars, disagreement between spectroscopic and interferometric effective temperatures has called the reliability of the temperature scale into question. We present new interferometric measurements of three metal-poor benchmark stars, HD 140283, HD 122563, and HD 103095, from which we determine their effective temperatures. The angular sizes of all the stars were determined from observations with the PAVO beam combiner at visible wavelengths at the CHARA array, with additional observations of HD 103095 made with the VEGA instrument, also at the CHARA array. Together with photometrically derived bolometric fluxes, the angular diameters give a direct measurement of the effective temperature. For HD 140283, we find θLD = 0.324 ± 0.005 mas, Teff = 5787 ± 48 K; for HD 122563, θLD = 0.926 ± 0.011 mas, Teff = 4636 ± 37 K; and for HD 103095, θLD = 0.595 ± 0.007 mas, Teff = 5140 ± 49 K. Our temperatures for HD 140283 and HD 103095 are hotter than the previous interferometric measurements by 253 and 322 K, respectively. We find good agreement between our temperatures and recent spectroscopic and photometric estimates. We conclude some previous interferometric measurements have been affected by systematic uncertainties larger than their quoted errors.

  7. Calcium pectate chemistry causes growth to be stored in Chara corallina: a test of the pectate cycle.

    Science.gov (United States)

    Proseus, Timothy E; Boyer, John S

    2008-08-01

    Calcium pectate chemistry was reported to control the growth rate of cells of Chara corallina, and required turgor pressure (P) to do so. Accordingly, this chemistry should account for other aspects of growth, particularly the ability of plants to compensate for brief exposure to low P, that is, to 'store' growth. Live Chara cells or isolated walls were attached to a pressure probe, and P was varied. Low P caused growth to be inhibited in live cells, but when P returned to normal (0.5 MPa), a flush of growth completely compensated for that lost at low P for as long as 23-53 min. This growth storage was absent in isolated walls, mature cells and live cells exposed to cold, indicating that the cytoplasm delivered a metabolically derived growth factor needing P for its action. Because the cytoplasm delivered pectate needing P for its action, pectate was supplied to isolated walls at low P as though the cytoplasm had done so. Growth was stored while otherwise none occurred. It was concluded that a P-dependent cycle of calcium pectate chemistry not only controlled growth rate and new wall deposition, but also accounted for stored growth.

  8. Seasonality of Water Chemistry, Carbonate Production, and Biometric Features of Two Species of Chara in a Shallow Clear Water Lake

    Directory of Open Access Journals (Sweden)

    Andrzej Pukacz

    2014-01-01

    Full Text Available The objective of this study was to analyze the temporal variability of biometric features and the carbonate production of two charophytes: Chara polyacantha A. Braun and Chara rudis A. Braun against the background of the physical-chemical properties of water. The investigation was carried out in a small, mid-forest Lake Jasne (western Poland. It is a polymictic, mesotrophic, hardwater ecosystem dominated by charophyte vegetation. Each month, 10 individuals of each species were characterized in terms of morphometric features, fresh and dry weight, and the percentage of calcium carbonate. Additionally, physical-chemical parameters of the water were studied. The results of physical-chemical analyses indicated similar habitat conditions for both species. Despite smaller dry weight C. polyacantha was characterized by greater morphological variability and higher rates of growth and percentage share of calcium carbonate in dry mass than C. rudis. The percentage of calcium carbonates in dry mass did not differ significantly between the species and exceeded 60%, reaching the maximum (76% in C. polyacantha in July and August. For both species, distinct correlations between the structure of biomass and morphological features were found. The obtained results show the great importance of charophyte vegetation in carbon cycling and functioning of lake ecosystems.

  9. Seasonality of water chemistry, carbonate production, and biometric features of two species of Chara in a shallow clear water lake.

    Science.gov (United States)

    Pukacz, Andrzej; Pełechaty, Mariusz; Frankowski, Marcin; Kowalski, Artur; Zwijacz-Koszałka, Kinga

    2014-01-01

    The objective of this study was to analyze the temporal variability of biometric features and the carbonate production of two charophytes: Chara polyacantha A. Braun and Chara rudis A. Braun against the background of the physical-chemical properties of water. The investigation was carried out in a small, mid-forest Lake Jasne (western Poland). It is a polymictic, mesotrophic, hardwater ecosystem dominated by charophyte vegetation. Each month, 10 individuals of each species were characterized in terms of morphometric features, fresh and dry weight, and the percentage of calcium carbonate. Additionally, physical-chemical parameters of the water were studied. The results of physical-chemical analyses indicated similar habitat conditions for both species. Despite smaller dry weight C. polyacantha was characterized by greater morphological variability and higher rates of growth and percentage share of calcium carbonate in dry mass than C. rudis. The percentage of calcium carbonates in dry mass did not differ significantly between the species and exceeded 60%, reaching the maximum (76% in C. polyacantha) in July and August. For both species, distinct correlations between the structure of biomass and morphological features were found. The obtained results show the great importance of charophyte vegetation in carbon cycling and functioning of lake ecosystems.

  10. Spatio-temporal patterns of photosystem II activity and plasma-membrane proton flows in Chara corallina cells exposed to overall and local illumination

    NARCIS (Netherlands)

    Bulychev, A.A.; Vredenberg, W.J.

    2003-01-01

    Pulse-amplitude modulated microfluorometry and an extracellular pH microprobe were used to examine light-induced spatial heterogeneity of photosynthetic and H+-transporting activities in cells of Chara corallina Klein ex Willd. Subcellular domains featuring different PSII photochemical activities

  11. Proposal to consistently apply the International Code of Nomenclature of Prokaryotes (ICNP) to names of the oxygenic photosynthetic bacteria (cyanobacteria), including those validly published under the International Code of Botanical Nomenclature (ICBN)/International Code of Nomenclature for algae, fungi and plants (ICN), and proposal to change Principle 2 of the ICNP.

    Science.gov (United States)

    Pinevich, Alexander V

    2015-03-01

    This taxonomic note was motivated by the recent proposal [Oren & Garrity (2014) Int J Syst Evol Microbiol 64, 309-310] to exclude the oxygenic photosynthetic bacteria (cyanobacteria) from the wording of General Consideration 5 of the International Code of Nomenclature of Prokaryotes (ICNP), which entails unilateral coverage of these prokaryotes by the International Code of Nomenclature for algae, fungi, and plants (ICN; formerly the International Code of Botanical Nomenclature, ICBN). On the basis of key viewpoints, approaches and rules in the systematics, taxonomy and nomenclature of prokaryotes it is reciprocally proposed to apply the ICNP to names of cyanobacteria including those validly published under the ICBN/ICN. For this purpose, a change to Principle 2 of the ICNP is proposed to enable validation of cyanobacterial names published under the ICBN/ICN rules. © 2015 IUMS.

  12. Occurrence of arsenic species in algae and freshwater plants of an extreme arid region in northern Chile, the Loa River Basin.

    Science.gov (United States)

    Pell, Albert; Márquez, Anna; López-Sánchez, José Fermín; Rubio, Roser; Barbero, Mercedes; Stegen, Susana; Queirolo, Fabrizio; Díaz-Palma, Paula

    2013-01-01

    This study reports data on arsenic speciation in two green algae species (Cladophora sp. and Chara sp.) and in five aquatic plants (Azolla sp., Myriophyllum aquaticum, Phylloscirpus cf. desserticola, Potamogeton pectinatus, Ruppia filifolia and Zannichellia palustris) from the Loa River Basin in the Atacama Desert (northern Chile). Arsenic content was measured by Mass spectrometry coupled with Inductively Coupled Plasma (ICP-MS), after acidic digestion. Liquid chromatography coupled to ICP-MS was used for arsenic speciation, using both anionic and cationic chromatographic exchange systems. Inorganic arsenic compounds were the main arsenic species measured in all samples. The main arsenic species in the extracts of freshwater algae and plants were arsenite and arsenate, whereas glycerol-arsenosugar (gly-sug), dimethylarsinic acid (DMA) and methylarsonic acid (MA) were present only as minor constituents. Of the samples studied, algae species accumulated more arsenic than aquatic plants. Total arsenic content ranged from 182 to 11100 and from 20 to 248 mg As kg(-1) (d.w.) in algae and freshwater plants, respectively. In comparison with As concentration in water samples, there was hyper-accumulation (>0.1% d.w.) in Cladophora sp. Copyright © 2012 Elsevier Ltd. All rights reserved.

  13. Tonoplast anion channel activity modulation by pH in Chara corallina.

    Science.gov (United States)

    Berecki, G; Eijken, M; Van Iren, F; Van Duijn, B

    2001-11-15

    The patch-clamp technique was used to investigate regulation of anion channel activity in the tonoplast of Chara corallina in response to changing proton and calcium concentrations on both sides of the membrane. These channels are known to be Ca2+-dependent, with conductances in the range of 37 to 48 pS at pH 7.4. By using low pH at the vacuolar side (either pH(vac) 5.3 or 6.0) and a cytosolic pH (pH(cyt)) varying in a range of 4.3 to 9.0, anion channel activity and single-channel conductance could be reversibly modulated. In addition, Ca2+-sensitivity of the channels was markedly influenced by pH changes. At pH(cyt) values of 7.2 and 7.4 the half-maximal concentration (EC50) for calcium activation was 100-200 microm, whereas an EC(50) of about 5 microm was found at a pH(cyt) of 6.0. This suggests an improved binding of Ca2+ ions to the channel protein at more acidic cytoplasm. At low pH(cyt), anion channel activity and mean open times were voltage-dependent. At pipette potentials (V(p)) of +100 mV, channel activity was approximately 15-fold higher than activity at negative pipette potentials and the mean open time of the channel increased. In contrast, at pH(cyt) 7.2, anion channel activity and the opening behavior seemed to be independent of the applied V(p). The kinetics of the channel could be further controlled by the Ca2+ concentration at the cytosolic membrane side: the mean open time significantly increased in the presence of a high cytosolic Ca2+ concentration. These results show that tonoplast anion channels are maintained in a highly active state in a narrow pH range, below the resting pH(cyt). A putative physiological role of the pH-dependent modulation of these anion channels is discussed.

  14. Sterol chemotaxonomy of marine pelagophyte algae.

    Science.gov (United States)

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

    2009-07-01

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

  15. Algae biodiesel - a feasibility report

    Directory of Open Access Journals (Sweden)

    Gao Yihe

    2012-04-01

    Full Text Available Abstract 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.

  16. Algae biodiesel - a feasibility report

    Science.gov (United States)

    2012-01-01

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

  17. Photobiological hydrogen production with switchable photosystem-II designer algae

    Science.gov (United States)

    Lee, James Weifu

    2014-02-18

    A process for enhanced photobiological H.sub.2 production using transgenic alga. The process includes inducing exogenous genes in a transgenic alga by manipulating selected environmental factors. In one embodiment inducing production of an exogenous gene uncouples H.sub.2 production from existing mechanisms that would downregulate H.sub.2 production in the absence of the exogenous gene. In other embodiments inducing an exogenous gene triggers a cascade of metabolic changes that increase H.sub.2 production. In some embodiments the transgenic alga are rendered non-regenerative by inducing exogenous transgenes for proton channel polypeptides that are targeted to specific algal membranes.

  18. A re-examination of the minor role of unstirred layers during the measurement of transport coefficients of Chara corallina internodes with the cell pressure probe.

    Science.gov (United States)

    Ye, Qing; Kim, Yangmin; Steudle, Ernst

    2006-05-01

    The impact of unstirred layers (USLs) during cell pressure probe experiments with Chara corallina internodes has been quantified. The results show that the hydraulic conductivity (Lp) measured in hydrostatic relaxations was not significantly affected by USLs even in the presence of high water flow intensities ('sweep-away effect'). During pressure clamp, there was a reversible reduction in Lp by 20%, which was explained by the constriction of water to aquaporins (AQPs) in the C. corallina membrane and a rapid diffusional equilibration of solutes in arrays where water protruded across AQPs. In osmotic experiments, Lp, and permeability (Ps) and reflection (sigma s) coefficients increased as external flow rate of medium increased, indicating some effects of external USLs. However, the effect was levelling off at 'usual' flow rates of 0.20-0.30 m s(-1) and in the presence of vigorous stirring by air bubbles, suggesting a maximum thickness of external USLs of around 30 microm including the cell wall. Because the diameters of internodes were around 1 mm, internal USLs could have played a significant or even a dominating role, at least in the presence of the rapidly permeating solutes used [acetone, 2-propanol and dimethylformamide (DMF)]. A comparison of calculated (diffusion kinetics) and of measured permeabilities indicated an upper limit of the contribution of USLs for the rapidly moving solute acetone of 29%, and of 15% for the less rapidly permeating DME The results throw some doubt on recent claims that in C. corallina, USLs rather than the cell membrane dominate solute uptake, at least for the most rapidly moving solute acetone.

  19. Effects of lanthanum on calcium and magnesium contents and cytoplasmic streaming of internodal cells of Chara corallina.

    Science.gov (United States)

    Li, Zijie; Zhang, Zhiyong; Yu, Ming; Zhou, Yunlong; Zhao, Yuliang

    2011-10-01

    Biological and environmental effects of lanthanide series of elements have received much attention recently due to their wide applications. In this study, effects of La(3+) treatments on calcium and magnesium concentrations as well as cytoplasmic streaming of internodal cells of Chara corallina were investigated. At all treatment concentrations (10, 100, and 1,000 μM), La(3+) significantly decreased calcium concentrations in the cell-wall fractions after 5-h treatments. Calcium concentrations in the cell contents and magnesium concentrations in the cell-wall fractions were reduced by 100 and 1,000 μM La(3+) treatments. However, cytoplasmic streaming as an indicator of [Ca(2+)](cyt) was only inhibited at the highest La(3+) concentration (1,000 μM). The results suggest that La(3+) may affect cellular calcium homeostasis by actions other than as a simple Ca(2+) antagonist. La(3+) could partially compensate for calcium deficiency at certain concentrations.

  20. Studies on alkaline band formation in Chara corallina: ameliorating effect of Ca2+ on inhibition induced by osmotic shock.

    Science.gov (United States)

    Shimmen, Teruo; Yonemura, Satoko; Negoro, Mio; Lucas, William J

    2003-09-01

    Although the decrease in cell turgor by application of sorbitol to the external medium did not inhibit the alkaline band formation in Chara corallina, recovery of normal turgor severely inhibited it. Alkaline-loading analysis suggested that the inhibition of alkaline band formation was caused by inhibition of HCO(3)(-) influx but not that of OH(-) efflux. In the presence of 10 mM CaCl(2), the capacity of alkaline band formation was maintained during osmotic treatment. Cells could not form alkaline bands, when plasmolysis was induced by application of sorbitol at a higher concentration. Addition of 10 mM CaCl(2) could ameliorate the inhibition caused by plasmolyis.

  1. Involvement of protein synthesis in recovery from refractory period of electrical depolarization induced by osmotic stimulation in Chara corallina.

    Science.gov (United States)

    Shimmen, Teruo

    2011-09-01

    Upon addition of sorbitol to the external medium of an internodal cell of Chara corallina, a transient depolarization is induced at its nodal end (Shimmen in Plant Cell Physiol 44:1215-1224, 2003). In the present study, refractory period was found to be very long, 2-4 h. Recovery from refractoriness was completely inhibited by inhibitors of eukaryote-type protein synthesis, cycloheximide or anisomysin, but not by inhibitors of prokaryote-type protein synthesis. This suggested that proteinous factor(s) responsible for generation of the depolarization is lost or inactivated upon depolarization and synthesized during the resting state. Low temperature, which is supposed to inhibit protein synthesis, also inhibited recovery from refractoriness. When unstimulated internodal cells were incubated in the medium containing an inhibitor of eukaryote-type protein synthesis, generation of the depolarization was almost completely inhibited. This result suggested that the factor is slowly turning over even in the absence of osmotic stimulation.

  2. The occurrence and removal of algae (including cyanobacteria) and ...

    African Journals Online (AJOL)

    Cyanobacterial bloom formation in freshwaters, such as rivers, lakes and dams, is known to occur throughout the world. The Vaalkop Dam, which serves as source to the Vaalkop drinking water treatment works (DWTW), is no exception. Blooms of cyanobacteria occur annually in Vaalkop Dam as well as in dams from which ...

  3. A cohesion/tension mechanism explains the gating of water channels (aquaporins) in Chara internodes by high concentration.

    Science.gov (United States)

    Ye, Qing; Wiera, Boguslaw; Steudle, Ernst

    2004-02-01

    Isolated internodes of Chara corallina have been used to study the gating of aquaporins (water channels) in the presence of high concentrations of osmotic solutes of different size (molecular weight). Osmolytes were acetone and three glycol ethers: ethylene glycol monomethyl ether (EGMME), diethylene glycol monomethyl ether (DEGMME), and triethylene glycol monoethyl ether (TEGMEE). The 'osmotic efficiency' of osmolytes was quite different. Their reflection coefficients ranged between 0.15 (acetone), 0.59 (EGMME), 0.78 (DEGMME), and 0.80 (TEGMEE). Bulk water permeability (Lp) and diffusive permeabilities (Ps) of heavy water (HDO), hydrogen peroxide (H2O2), acetone, and glycol ethers (EGMME, DEGMME, and TEGMEE) were measured using a cell pressure probe. Cells were treated with different concentrations of osmotic solutes of up to 800 mM ( approximately 2.0 MPa of osmotic pressure). Inhibition of aquaporin activity increased with both increasing concentration and size of solutes (reflection coefficients). As cell Lp decreased, Ps increased, indicating that water and solutes used different passages across the plasma membrane. Similar to earlier findings of an osmotic gating of ion channels, a cohesion/tension model of the gating of water channels in Chara internodes by high concentration is proposed. According to the model, tensions (negative pressures) within water channels affected the open/closed state by changing the free energy between states and favoured a distorted/collapsed rather than the open state. They should have differed depending on the concentration and size of solutes that are more or less excluded from aquaporins. The bigger the solute, the lower was the concentration required to induce a reversible closure of aquaporins, as predicted by the model.

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

    Energy Technology Data Exchange (ETDEWEB)

    None

    2010-01-15

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

  5. Shewanella algae in acute gastroenteritis

    Directory of Open Access Journals (Sweden)

    S Dey

    2015-01-01

    Full Text Available Shewanella algae is an emerging bacteria rarely implicated as a human pathogen. Previously reported cases of S. algae have mainly been associated with direct contact with seawater. Here we report the isolation of S. algae as the sole etiological agent from a patient suffering from acute gastroenteritis with bloody diarrhoea. The bacterium was identified by automated identification system and 16S rRNA gene sequence analysis. Our report highlights the importance of looking for the relatively rare aetiological agents in clinical samples that does not yield common pathogens. It also underscores the usefulness of automated systems in identification of rare pathogens.

  6. Transgenic algae engineered for higher performance

    Science.gov (United States)

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

    2014-10-21

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

  7. XET activity is found near sites of growth and cell elongation in bryophytes and some green algae: new insights into the evolution of primary cell wall elongation.

    Science.gov (United States)

    Van Sandt, Vicky S T; Stieperaere, Herman; Guisez, Yves; Verbelen, Jean-Pierre; Vissenberg, Kris

    2007-01-01

    In angiosperms xyloglucan endotransglucosylase (XET)/hydrolase (XTH) is involved in reorganization of the cell wall during growth and development. The location of oligo-xyloglucan transglucosylation activity and the presence of XTH expressed sequence tags (ESTs) in the earliest diverging extant plants, i.e. in bryophytes and algae, down to the Phaeophyta was examined. The results provide information on the presence of an XET growth mechanism in bryophytes and algae and contribute to the understanding of the evolution of cell wall elongation in general. Representatives of the different plant lineages were pressed onto an XET test paper and assayed. XET or XET-related activity was visualized as the incorporation of fluorescent signal. The Physcomitrella genome database was screened for the presence of XTHs. In addition, using the 3' RACE technique searches were made for the presence of possible XTH ESTs in the Charophyta. XET activity was found in the three major divisions of bryophytes at sites corresponding to growing regions. In the Physcomitrella genome two putative XTH-encoding cDNA sequences were identified that contain all domains crucial for XET activity. Furthermore, XET activity was located at the sites of growth in Chara (Charophyta) and Ulva (Chlorophyta) and a putative XTH ancestral enzyme in Chara was identified. No XET activity was identified in the Rhodophyta or Phaeophyta. XET activity was shown to be present in all major groups of green plants. These data suggest that an XET-related growth mechanism originated before the evolutionary divergence of the Chlorobionta and open new insights in the evolution of the mechanisms of primary cell wall expansion.

  8. Algae biotechnology: products and processes

    National Research Council Canada - National Science Library

    Bux, F; Chisti, Yusuf

    2016-01-01

    This book examines the utilization of algae for the development of useful products and processes with the emphasis towards green technologies and processes, and the requirements to make these viable...

  9. Algae: America's Pathway to Independence

    National Research Council Canada - National Science Library

    Custer, James

    2007-01-01

    .... Oil dependency is an unacceptable risk to U.S. national strategy. This paper advocates independence from foreign oil by converting the national transportation fleet to biodiesel derived from algae...

  10. Bioconcentration of tetrachlorobenzene in marine algae

    Science.gov (United States)

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

    1997-09-01

    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).

  11. [Chemical constituents from red alga Corallina pilulifera].

    Science.gov (United States)

    Yuan, Zhao-Hui; Han, Li-Jun; Fan, Xiao; Li, Shuai; Shi, Da-Yong; Sun, Jie; Ma, Ming; Yang, Yong-Chun; Shi, Jian-Gong

    2006-11-01

    To investigate the chemical constituents of red alga Corallina pilulifera. Compounds were isolated by normal phase silica gel and Sephadex LH - 20 gel column chromatography, reverse phase HPLC and recrystallization. Their structures were elucidated by spectroscopic methods including MS, 1H-NMR, 13C-NMR, HSQC, HMBC. Cytotoxicity of the compounds was screened by using standard MTT method. Seven compounds were isolated from red alga C. pilulifera, their structures were identified as (E) -phytol epoxide (1), phytenal (2), phytol (3), dehydrovomifoliol (4), loliolide (5), 3beta-hydroxy-5alpha, 6alpha-epoxy-7-megastigmene-9-one (6), 4-hydroxybenzaldehyde (7). All of the compounds were obtained from this species for the first time. These compounds were inactive (IC50 > 10 microg x mL(-1)) in the MTT assay.

  12. Autoradiographic studies on [sup 3]H-fucose incorporation into manubria and its translocation to antheridial space during spermatogenesis in Chara vulgaris L

    Energy Technology Data Exchange (ETDEWEB)

    Gosek, A.; Kwiatkowska, M. (Lodz Univ. (Poland))

    1993-01-01

    The internal space of antheridium in Chara vulgaris L. is filled with the PAS-positive polysaccharide mucilage. It is produced and secreted by non-generative, polyploidal cells - manubria. Autoradiographic studies with the use of [sup 3]H-fucose have shown that this precursor is incorporated into polysaccharidial compounds at the manubrium surface. The dynamics of this process is different in proliferative phase than after symplasmic isolation of antheridium. The translocation of mucilage into antheridial space is very intensive, especially at the older developmental stages of antheridium. The data obtained after 12-hour post incubation indicated secondary metabolic changes of mucilage. The decrease in total radioactivity per investigated section is most intensive by the end of spermatogenesis. These facts seem to confirm the assumption about nutritive role of mucilage filling Chara antheridium during the process of spermatogenesis. (author). 19 refs, 3 figs, 2 tabs.

  13. Localisation and substrate specificities of transglycanases in charophyte algae relate to development and morphology.

    Science.gov (United States)

    Herburger, Klaus; Ryan, Louise M; Popper, Zoë A; Holzinger, Andreas

    2018-01-29

    Cell wall-modifying enzymes have been previously investigated in charophyte green algae (CGA) in cultures of uniform age, giving limited insight into their roles. Therefore, we investigated the in situ localisation and specificity of enzymes acting on hemicelluloses in CGA genera of different morphologies and developmental stages. In vivo transglycosylation between xyloglucan and an endogenous donor in filamentous Klebsormidium and Zygnema was observed in longitudinal cell walls of young (1 month) but not old cells (1 year), suggesting that it has a role in cell growth. By contrast, in parenchymatous Chara , transglycanase action occurred in all cell planes. In Klebsormidium and Zygnema , the location of enzyme action mainly occurred in regions where xyloglucans and mannans, and to a lesser extent mixed-linkage β-glucan (MLG), were present, indicating predominantly xyloglucan:xyloglucan endotransglucosylase (XET) activity. Novel transglycosylation activities between xyloglucan and xylan, and xyloglucan and galactomannan were identified in vitro in both genera. Our results show that several cell wall-modifying enzymes are present in CGA, and that differences in morphology and cell age are related to enzyme localisation and specificity. This indicates an evolutionary significance of cell wall modifications, as similar changes are known in their immediate descendants, the land plants. This article has an associated First Person interview with the first author of the paper. © 2018. Published by The Company of Biologists Ltd.

  14. Thermal algae in certain radioactive springs in Japan, (3)

    International Nuclear Information System (INIS)

    Mifune, Masaaki; Hirose, Hiroyuki.

    1982-01-01

    Shikano Hot Springs are located at five km to the south of Hamamura Station on the Sanin Line in Tottori Prefecture. The water temperature and the pH of the springs are 40.2 - 61.2 0 C, and 7.5 - 7.8, respectively. They belong to simple thermals. Hamamura Hot Springs are located in the neighbourhood of Hamamura Station. The highest radon content of the hot springs is 175.1 x 10 -10 Ci/l, and the great part of the springs belong to radioactive ones. From the viewpoint of the major ionic constituents, they are also classified under weak salt springs, sulfated salt springs, and simple thermals. Regarding the habitates of the algal flora, the water temperature and the pH of the springs are 28.0 - 68.0 0 C, and 6.8 - 7.4, respectively. The thermal algae found by Ikoma and Doi at Hamamura Hot Springs were two species of Cyanophyceae. By the authors, nine species and one variety of Cyanophyceae including Ikoma and Doi's two species were newly found at Shikano and Hamamura Hot Springs. Chlorophyceous alga was not found. The dominant thermal algae of these hot springs were Mastigocladus laminosus, and the other algae which mainly consist of Oscillatoriaceous algae. From these points, it seems that the thermal algae of Shikano and Hamamura Hot Springs belong to the normal type of thermal algae, and they are different from the thermal algae of Ikeda Mineral Springs and Masutomi Hot Springs which belong to strongly radioactive springs. (author)

  15. Prokaryotic community profiling of local algae wastewaters using advanced 16S rRNA gene sequencing.

    Science.gov (United States)

    Limayem, Alya; Micciche, Andrew; Nayak, Bina; Mohapatra, Shyam

    2018-01-01

    Algae biomass-fed wastewaters are a promising source of lipid and bioenergy manufacture, revealing substantial end-product investment returns. However, wastewaters would contain lytic pathogens carrying drug resistance detrimental to algae yield and environmental safety. This study was conducted to simultaneously decipher through high-throughput advanced Illumina 16S ribosomal RNA (rRNA) gene sequencing, the cultivable and uncultivable bacterial community profile found in a single sample that was directly recovered from the local wastewater systems. Samples were collected from two previously documented sources including anaerobically digested (AD) municipal wastewater and swine wastewater with algae namely Chlorella spp. in addition to control samples, swine wastewater, and municipal wastewater without algae. Results indicated the presence of a significant level of Bacteria in all samples with an average of approximately 95.49% followed by Archaea 2.34%, in local wastewaters designed for algae cultivation. Taxonomic genus identification indicated the presence of Calothrix, Pseudomonas, and Clostridium as the most prevalent strains in both local municipal and swine wastewater samples containing algae with an average of 17.37, 12.19, and 7.84%, respectively. Interestingly, swine wastewater without algae displayed the lowest level of Pseudomonas strains algae indicates potential coexistence between these strains and algae microenvironment, suggesting further investigations. This finding was particularly relevant for the earlier documented adverse effects of some nosocomial Pseudomonas strains on algae growth and their multidrug resistance potential, requiring the development of targeted bioremediation with regard to the beneficial flora.

  16. Algae as a Biofuel: Renewable Source for Liquid Fuel

    Directory of Open Access Journals (Sweden)

    Vijay Kant Pandey

    2016-09-01

    Full Text Available Biofuels produced by algae may provide a feasible alternative to fossil fuels like petroleum sourced fuels. However, looking to limited fossil fuel associated with problems, intensive efforts have been given to search for alternative biofuels like biodiesel. Algae are ubiquitous on earth, have potential to produce biofuel. However, technology of biofuel from algae facing a number of hurdles before it can compete in the fuel market and be broadly organized. Different challenges include strain identification and improvement of algal biomass, both in terms of biofuel productivity and the production of other products to improve the economics of the entire system. Algal biofuels could be made more cost effective by extracting other valuable products from algae and algal strains. Algal oil can be prepared by culture of algae on municipal and industrial wastewaters. Photobioreactors methods provide a controlled environment that can be tailored to the specific demands of high production of algae to attain a consistently good yield of biofuel. The algal biomass has been reported to yield high oil contents and have good amount of the biodiesel production capacity. In this article, it has been attempted to review to elucidate the approaches for making algal biodiesel economically competitive with respect to petrodiesel. Consequently, R & D work has been carried out for the growth, harvesting, oil extraction and conversion to biodiesel from algal sources.

  17. Development of Green Fuels From Algae - The University of Tulsa

    Energy Technology Data Exchange (ETDEWEB)

    Crunkleton, Daniel; Price, Geoffrey; Johannes, Tyler; Cremaschi, Selen

    2012-12-03

    The general public has become increasingly aware of the pitfalls encountered with the continued reliance on fossil fuels in the industrialized world. In response, the scientific community is in the process of developing non-fossil fuel technologies that can supply adequate energy while also being environmentally friendly. In this project, we concentrate on green fuels which we define as those capable of being produced from renewable and sustainable resources in a way that is compatible with the current transportation fuel infrastructure. One route to green fuels that has received relatively little attention begins with algae as a feedstock. Algae are a diverse group of aquatic, photosynthetic organisms, generally categorized as either macroalgae (i.e. seaweed) or microalgae. Microalgae constitute a spectacularly diverse group of prokaryotic and eukaryotic unicellular organisms and account for approximately 50% of global organic carbon fixation. The PI's have subdivided the proposed research program into three main research areas, all of which are essential to the development of commercially viable algae fuels compatible with current energy infrastructure. In the fuel development focus, catalytic cracking reactions of algae oils is optimized. In the species development project, genetic engineering is used to create microalgae strains that are capable of high-level hydrocarbon production. For the modeling effort, the construction of multi-scaled models of algae production was prioritized, including integrating small-scale hydrodynamic models of algae production and reactor design and large-scale design optimization models.

  18. New records of marine algae in Vietnam

    Science.gov (United States)

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

    2015-06-01

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

  19. Gain and loss of polyadenylation signals during evolution of green algae

    OpenAIRE

    Wodniok, Sabina; Simon, Andreas; Glöckner, Gernot; Becker, Burkhard

    2007-01-01

    Abstract Background The Viridiplantae (green algae and land plants) consist of two monophyletic lineages: the Chlorophyta and the Streptophyta. Most green algae belong to the Chlorophyta, while the Streptophyta include all land plants and a small group of freshwater algae known as Charophyceae. Eukaryotes attach a poly-A tail to the 3' ends of most nuclear-encoded mRNAs. In embryophytes, animals and fungi, the signal for polyadenylation contains an A-rich sequence (often AAUAAA or related seq...

  20. The Cell Walls of Green Algae: A Journey through Evolution and Diversity

    OpenAIRE

    Domozych, David S.; Ciancia, Marina; Fangel, Jonatan U.; Mikkelsen, Maria Dalgaard; Ulvskov, Peter; Willats, William G. T.

    2012-01-01

    The green algae represent a large group of morphologically diverse photosynthetic eukaryotes that occupy virtually every photic habitat on the planet. The extracellular coverings of green algae including cell walls are also diverse. A recent surge of research in green algal cell walls fueled by new emerging technologies has revealed new and critical insight concerning these coverings. For example, the late divergent taxa of the Charophycean Green Algae possess cell walls containing assemblag...

  1. Algae Bloom in a Lake

    Directory of Open Access Journals (Sweden)

    David Sanabria

    2008-01-01

    Full Text Available The objective of this paper is to determine the likelihood of an algae bloom in a particular lake located in upstate New York. The growth of algae in this lake is caused by a high concentration of phosphorous that diffuses to the surface of the lake. Our calculations, based on Fick's Law, are used to create a mathematical model of the driving force of diffusion for phosphorous. Empirical observations are also used to predict whether the concentration of phosphorous will diffuse to the surface of this lake within a specified time and under specified conditions.

  2. Interferometric diameters of five evolved intermediate-mass planet-hosting stars measured with PAVO at the CHARA Array

    Science.gov (United States)

    White, T. R.; Huber, D.; Mann, A. W.; Casagrande, L.; Grunblatt, S. K.; Justesen, A. B.; Silva Aguirre, V.; Bedding, T. R.; Ireland, M. J.; Schaefer, G. H.; Tuthill, P. G.

    2018-04-01

    Debate over the planet occurrence rates around intermediate-mass stars has hinged on the accurate determination of masses of evolved stars, and has been exacerbated by a paucity of reliable, directly-measured fundamental properties for these stars. We present long-baseline optical interferometry of five evolved intermediate-mass (˜ 1.5 M⊙) planet-hosting stars using the PAVO beam combiner at the CHARA Array, which we combine with bolometric flux measurements and parallaxes to determine their radii and effective temperatures. We measured the radii and effective temperatures of 6 Lyncis (5.12±0.16 R⊙, 4949±58 K), 24 Sextantis (5.49±0.18 R⊙, 4908±65 K), κ Coronae Borealis (4.77±0.07 R⊙, 4870±47 K), HR 6817 (4.45±0.08 R⊙, 5013±59 K), and HR 8641 (4.91±0.12 R⊙, 4950±68 K). We find disagreements of typically 15 % in angular diameter and ˜ 200 K in temperature compared to interferometric measurements in the literature, yet good agreement with spectroscopic and photometric temperatures, concluding that the previous interferometric measurements may have been affected by systematic errors exceeding their formal uncertainties. Modelling based on BaSTI isochrones using various sets of asteroseismic, spectroscopic, and interferometric constraints tends to favour slightly (˜ 15 %) lower masses than generally reported in the literature.

  3. 21 CFR 184.1120 - Brown algae.

    Science.gov (United States)

    2010-04-01

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

  4. 21 CFR 184.1121 - Red algae.

    Science.gov (United States)

    2010-04-01

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

  5. Ion and metabolite transport in the chloroplast of algae: lessons from land plants.

    Science.gov (United States)

    Marchand, Justine; Heydarizadeh, Parisa; Schoefs, Benoît; Spetea, Cornelia

    2018-03-14

    Chloroplasts are endosymbiotic organelles and play crucial roles in energy supply and metabolism of eukaryotic photosynthetic organisms (algae and land plants). They harbor channels and transporters in the envelope and thylakoid membranes, mediating the exchange of ions and metabolites with the cytosol and the chloroplast stroma and between the different chloroplast subcompartments. In secondarily evolved algae, three or four envelope membranes surround the chloroplast, making more complex the exchange of ions and metabolites. Despite the importance of transport proteins for the optimal functioning of the chloroplast in algae, and that many land plant homologues have been predicted, experimental evidence and molecular characterization are missing in most cases. Here, we provide an overview of the current knowledge about ion and metabolite transport in the chloroplast from algae. The main aspects reviewed are localization and activity of the transport proteins from algae and/or of homologues from other organisms including land plants. Most chloroplast transporters were identified in the green alga Chlamydomonas reinhardtii, reside in the envelope and participate in carbon acquisition and metabolism. Only a few identified algal transporters are located in the thylakoid membrane and play role in ion transport. The presence of genes for putative transporters in green algae, red algae, diatoms, glaucophytes and cryptophytes is discussed, and roles in the chloroplast are suggested. A deep knowledge in this field is required because algae represent a potential source of biomass and valuable metabolites for industry, medicine and agriculture.

  6. Designer proton-channel transgenic algae for photobiological hydrogen production

    Science.gov (United States)

    Lee, James Weifu [Knoxville, TN

    2011-04-26

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

  7. Scenario studies for algae production

    NARCIS (Netherlands)

    Slegers, P.M.

    2014-01-01

    Microalgae are a promising biomass for the biobased economy to produce food, feed, fuel, chemicals and materials. So far, large-scale production of algae is limited and as a result estimates on the performance of such large systems are scarce. There is a need to estimate large-scale biomass

  8. Algae. LC Science Tracer Bullet.

    Science.gov (United States)

    Niskern, Diana, Comp.

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

  9. Composition, mineral profiles and characterization of the ash component in 12 algae samples

    Science.gov (United States)

    Algae have been used as food, feed, fertilizer, and lately as an attractive biomass for renewable energy. Key advantages of algae include prolific growth rates, the ability to grow on lands that are marginal for other agricultural purposes, and the ability to clean up water resources with excess nu...

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

    Science.gov (United States)

    Yuyama, Ikuko; Higuchi, Tomihiko

    2014-01-01

    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

  11. Macro algae as substrate for biogas production

    DEFF Research Database (Denmark)

    Møller, Henrik; Sarker, Shiplu; Gautam, Dhan Prasad

    Algae as a substrate for biogas is superior to other crops since it has a much higher yield of biomass per unit area and since algae grows in the seawater there will be no competition with food production on agricultural lands. So far, the progress in treating different groups of algae as a source...... of energy is promising. In this study 5 different algae types were tested for biogas potential and two algae were subsequent used for co-digestion with manure. Green seaweed, Ulva lactuca and brown seaweed Laminaria digitata was co-digested with cattle manure at mesophilic and thermophilic condition...

  12. Amphiregulin as an autocrine growth factor for c-Ha-ras- and c-erbB-2-transformed human mammary epithelial cells.

    OpenAIRE

    Normanno, N; Selvam, M P; Qi, C F; Saeki, T; Johnson, G; Kim, N; Ciardiello, F; Shoyab, M; Plowman, G; Brandt, R

    1994-01-01

    Amphiregulin (AR), a member of the epidermal growth factor (EGF) family, was found to be as potent as EGF in stimulating the anchorage-dependent growth (ADG) of immortalized, nontransformed human mammary epithelial MCF-10A cells. MCF-10A cells transformed by either an activated human c-Ha-ras protooncogene (MCF-10A ras) or by overexpression of a nonactivated rat c-neu gene (MCF-10A neu) exhibited a 35% reduction in the response to AR in ADG when compared to MCF-10A cells, but AR was still as ...

  13. Interferometric measurements of dry mass content in nuclei and cytoplasm in the life cycle of antheridial filaments cells of Chara vulgaris L. in their successive developmental stages

    Directory of Open Access Journals (Sweden)

    Hanna Kuran

    2015-01-01

    Full Text Available Interferometric measurements of the nucleus and cytoplasm dry mass during interphase in the successive stages of development of antheridial filaments of Chara vulgaris demonstrated that the dry mass and surface area of cell nuclei double in size in each of the successive generations of the filaments, whereas neither the surface nor the dry mass of the cytoplasm increase in such proportion in the same period. In the successive stages of development of the antheridial filaments the dry mass and surface area of the nuclei and cytoplasm gradually diminish.

  14. Evolution and diversity of plant cell walls: from algae to flowering plants.

    Science.gov (United States)

    Popper, Zoë A; Michel, Gurvan; Hervé, Cécile; Domozych, David S; Willats, William G T; Tuohy, Maria G; Kloareg, Bernard; Stengel, Dagmar B

    2011-01-01

    All photosynthetic multicellular Eukaryotes, including land plants and algae, have cells that are surrounded by a dynamic, complex, carbohydrate-rich cell wall. The cell wall exerts considerable biological and biomechanical control over individual cells and organisms, thus playing a key role in their environmental interactions. This has resulted in compositional variation that is dependent on developmental stage, cell type, and season. Further variation is evident that has a phylogenetic basis. Plants and algae have a complex phylogenetic history, including acquisition of genes responsible for carbohydrate synthesis and modification through a series of primary (leading to red algae, green algae, and land plants) and secondary (generating brown algae, diatoms, and dinoflagellates) endosymbiotic events. Therefore, organisms that have the shared features of photosynthesis and possession of a cell wall do not form a monophyletic group. Yet they contain some common wall components that can be explained increasingly by genetic and biochemical evidence.

  15. Phycobiliproteins: A Novel Green Tool from Marine Origin Blue-Green Algae and Red Algae.

    Science.gov (United States)

    Chandra, Rashmi; Parra, Roberto; Iqbal, Hafiz M N

    2017-01-01

    Marine species are comprising about a half of the whole global biodiversity; the sea offers an enormous resource for novel bioactive compounds. Several of the marine origin species show multifunctional bioactivities and characteristics that are useful for a discovery and/or reinvention of biologically active compounds. For millennia, marine species that includes cyanobacteria (blue-green algae) and red algae have been targeted to explore their enormous potential candidature status along with a wider spectrum of novel applications in bio- and non-bio sectors of the modern world. Among them, cyanobacteria are photosynthetic prokaryotes, phylogenetically a primitive group of Gramnegative prokaryotes, ranging from Arctic to Antarctic regions, capable of carrying out photosynthesis and nitrogen fixation. In the recent decade, a great deal of research attention has been paid on the pronouncement of bio-functional proteins along with novel peptides, vitamins, fine chemicals, renewable fuel and bioactive compounds, e.g., phycobiliproteins from marine species, cyanobacteria and red algae. Interestingly, they are extensively commercialized for natural colorants in food and cosmetics, antimicrobial, antioxidant, anti-inflammatory, neuroprotective, hepatoprotective agents and fluorescent neo-glycoproteins as probes for single particle fluorescence imaging fluorescent applications in clinical and immunological analysis. However, a comprehensive knowledge and technological base for augmenting their commercial utilities are lacking. Therefore, this paper will provide an overview of the phycobiliproteins-based research literature from marine cyanobacteria and red algae. This review is also focused towards analyzing global and commercial activities with application oriented-based research. Towards the end, the information is also given on the potential biotechnological and biomedical applications of phycobiliproteins. Copyright© Bentham Science Publishers; For any queries, please

  16. Inorganic carbon addition stimulates snow algae primary productivity

    Science.gov (United States)

    Hamilton, T. L.; Havig, J. R.

    2017-12-01

    Earth has experienced glacial/interglacial oscillations throughout its history. Today over 15 million square kilometers (5.8 million square miles) of Earth's land surface is covered in ice including glaciers, ice caps, and the ice sheets of Greenland and Antarctica, most of which are retreating as a consequence of increased atmospheric CO2. Glaciers are teeming with life and supraglacial snow and ice surfaces are often red due to blooms of photoautotrophic algae. Recent evidence suggests the red pigmentation, secondary carotenoids produced in part to thrive under high irradiation, lowers albedo and accelerates melt. However, there are relatively few studies that report the productivity of snow algae communities and the parameters that constrain their growth on snow and ice surfaces. Here, we demonstrate that snow algae primary productivity can be stimulated by the addition of inorganic carbon. We found an increase in light-dependent carbon assimilation in snow algae microcosms amended with increasing amounts of inorganic carbon. Our snow algae communities were dominated by typical cosmopolitan snow algae species recovered from Alpine and Arctic environments. The climate feedbacks necessary to enter and exit glacial/interglacial oscillations are poorly understood. Evidence and models agree that global Snowball events are accompanied by changes in atmospheric CO2 with increasing CO2 necessary for entering periods of interglacial time. Our results demonstrate a positive feedback between increased CO2 and snow algal productivity and presumably growth. With the recent call for bio-albedo effects to be considered in climate models, our results underscore the need for robust climate models to include feedbacks between supraglacial primary productivity, albedo, and atmospheric CO2.

  17. Cyclosis-related asymmetry of chloroplast-plasma membrane interactions at the margins of illuminated area in Chara corallina cells.

    Science.gov (United States)

    Dodonova, Svetlana O; Bulychev, Alexander A

    2011-10-01

    Cytoplasmic streaming in plant cells is an effective means of intracellular transport. The cycling of ions and metabolites between the cytosol and chloroplasts in illuminated cell regions may alter the cytoplasm composition, while directional flow of this modified cytoplasm may affect the plasma membrane and chloroplast activities in cell regions residing downstream of the illumination area. The impact of local illumination is predicted to be asymmetric because the cell regions located downstream and upstream in the cytoplasmic flow with respect to illumination area would be exposed to flowing cytoplasm whose solute composition was influenced by photosynthetic or dark metabolism. This hypothesis was checked by measuring H(+)-transporting activity of plasmalemma and chlorophyll fluorescence of chloroplasts in shaded regions of Chara corallina internodal cells near opposite borders of illuminated region (white light, beam width 2 mm). Both the apoplastic pH and chlorophyll fluorescence, recorded in shade regions at equal distances from illuminated area, exhibited asymmetric light-on responses depending on orientation of cytoplasmic streaming at the light-shade boundary. In the region where the cytoplasm flowed from illuminated area to the measurement area, the alkaline zone (a zone with high plasma membrane conductance) was formed within 4-min illumination, whereas no alkaline zone was observed in the area where cytoplasm approached the boundary from darkened regions. The results emphasize significance of cyclosis in lateral distribution of a functionally active intermediate capable of affecting the membrane transport across the plasmalemma, the functional activity of chloroplasts, and pattern formation in the plant cell.

  18. Effects of aluminum on plasma membrane as revealed by analysis of alkaline band formation in internodal cells of Chara corallina.

    Science.gov (United States)

    Takano, M; Shimmen, T

    1999-06-01

    To study the mechanism of aluminum toxicity in plant cells, the effects of aluminum on alkaline band formation were analyzed in the internodal cells of Chara. After cells were treated with AlCl3, they were examined for their capacity to develop alkaline bands. Treating cells with AlCl3 medium at pH 4.5 completely inhibited alkaline band formation. When either CaCl2 or malic acid was added to the AlCl3 medium (pH 4.5), it did not produce an ameliorative effect, whereas addition of both CaCl2 and malic acid induced a significant ameliorative effect. It was found that treatment at pH 4.5 in the absence of AlCl3 strongly inhibited alkaline band formation. This inhibition by the low pH (4.5) treatment was effectively ameliorated by CaCl2. At higher pH (5.0), malic acid alone produced a significant ameliorative effect on aluminum inhibition of alkaline band formation, but CaCl2 did not. Recovery from aluminum inhibition was also studied. When cells treated with AlCl3 at pH 4.5 were incubated in artificial pond water, they could not recover the capacity to develop alkaline band. When either malic acid or CaCl2 was added to artificial pond water, cells recovered their alkaline band formation. It was concluded that one of the primary targets of aluminum is the plasma membrane and that aluminum affects the plasma membrane from the cell exterior at the beginning of the treatment (within 24 h). It was also suggested that the aluminum treatment impairs the HCO3- influx mechanism but not the OH- efflux mechanism.

  19. Surface pH changes suggest a role for H+/OH-channels in salinity response of Chara australis.

    Science.gov (United States)

    Absolonova, Marketa; Beilby, Mary J; Sommer, Aniela; Hoepflinger, Marion C; Foissner, Ilse

    2017-12-15

    To understand salt stress, the full impact of salinity on plant cell physiology has to be resolved. Electrical measurements suggest that salinity inhibits the proton pump and opens putative H + /OH - channels all over the cell surface of salt sensitive Chara australis (Beilby and Al Khazaaly 2009; Al Khazaaly and Beilby 2012). The channels open transiently at first, causing a characteristic noise in membrane potential difference (PD), and after longer exposure remain open with a typical current-voltage (I/V) profile, both abolished by the addition of 1 mM ZnCl 2 , the main known blocker of animal H + channels. The cells were imaged with confocal microscopy, using fluorescein isothiocyanate (FITC) coupled to dextran 70 to illuminate the pH changes outside the cell wall in artificial fresh water (AFW) and in saline medium. In the early saline exposure, we observed alkaline patches (bright fluorescent spots) appearing transiently in random spatial distribution. After longer exposure, some of the spots became fixed in space. Saline also abolished or diminished the pH banding pattern observed in the untreated control cells. ZnCl 2 suppressed the alkaline spot formation in saline and the pH banding pattern in AFW. The osmotic component of the saline stress did not produce transient bright spots or affect banding. The displacement of H + from the cell wall charges, the H + /OH - channel conductance/density, and self-organization are discussed. No homologies to animal H + channels were found. Salinity activation of the H + /OH - channels might contribute to saline response in roots of land plants and leaves of aquatic angiosperms.

  20. Point mutation in activated c-Ha-ras gene of a chemically induced transplantable human pancreas carcinoma

    International Nuclear Information System (INIS)

    Maheshwari, K.K.; Parsa, I.

    1986-01-01

    The authors have reported a model of human pancreas carcinogenesis where repeated treatment with MNU of explants results in the development of transplantable carcinoma. This report compares the endonuclease digests of DNAs from normal human pancreas (HP) and MNU-induced transplantable tumor (HP-T1) analyzed with 32 P-labelled Ha-ras probe prepared from clone BS-9. The hybridization patterns of BamHI, BglII, EcoRI and HindIII digests of HP were significantly different from those of HP-T1. In EcoRI digests a 3.0 kb fragments of HP-T1 DNA hybridized with Ha-ras probe instead of a 4.3 kb fragments seen in HP DNA. The pattern for HindIII digests was similar to those of EcoRI. The BgIII digests of HP DNA revealed two hybridizing fragments of 8.0 and 4.3 kb whereas those of HP-T1 DNA fragments measured 8.5 and 4.0 kb. BamHI treated HP DNA showed only hybridizing fragments of 6.6 kb while the HP-T1 DNA showed to hybridizing fragments of 6.8 and 7.2 kb. The digested DNAs by HhaI, HinfI, KpnI, pstI, PvuII, SaII, SstI, TaqI and XbaI showed similar hybridization profiles. The point mutation in c-Ha-ras was examined in the HpaII and MspI double digests of both DNAs by 0.6 Kb SmaI fragments of pEJ. The hybridized fragments measured 412 and 355 bp in DNA digests from tumor and normal pancreas respectively

  1. Evaluation of Algae from the effluent of Dandot cement company ...

    African Journals Online (AJOL)

    Twenty genera and fifty species of algae have been reported from the effluent water of Dandot Cement Company. They include thirteen genera and thirty five species from Chlorophyceae; three genera and six species from Cyanophyceae and four genera and nine species from Bacillariophyceae. Camera Lucida drawings ...

  2. Synthetic polyester from algae oil.

    Science.gov (United States)

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

    2014-06-23

    Current efforts to technically use microalgae focus on the generation of fuels with a molecular structure identical to crude oil based products. Here we suggest a different approach for the utilization of algae by translating the unique molecular structures of algae oil fatty acids into higher value chemical intermediates and materials. A crude extract from a microalga, the diatom Phaeodactylum tricornutum, was obtained as a multicomponent mixture containing amongst others unsaturated fatty acid (16:1, 18:1, and 20:5) phosphocholine triglycerides. Exposure of this crude algae oil to CO and methanol with the known catalyst precursor [{1,2-(tBu2 PCH2)2C6H4}Pd(OTf)](OTf) resulted in isomerization/methoxycarbonylation of the unsaturated fatty acids into a mixture of linear 1,17- and 1,19-diesters in high purity (>99 %). Polycondensation with a mixture of the corresponding diols yielded a novel mixed polyester-17/19.17/19 with an advantageously high melting and crystallization temperature. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Growing swimming algae for bioenergy

    Science.gov (United States)

    Croze, Ottavio

    Biofuel production from photosynthetic microalgae is not commercially viable due to high processing costs. New engineering and biological solutions are being sought to reduce these costs by increasing processing efficiency (productivity per energy input). Important physics, however, is ignored. For example, the fluid dynamics of algal suspensions in photobioreactors (ponds or tube arrays) is non-trivial, particularly if the algae swim. Cell reorientation by passive viscous and gravitational torques (gyrotaxis) or active reorientation by light (phototaxis) cause swimming algae in suspension to structure in flows, even turbulent ones. This impacts the distribution and dispersion of swimmers, with significant consequences for photobioreactor operation and design. In this talk, I will describe a theory that predicts swimmer dispersion in laminar pipe flows. I will then then present experimental tests of the theory, as well as new results on the circadian suspension dynamics of the algaChlamydomonas reinhardtii in lab-scale photobioreactors. Finally, I will briefly consider the implications of our work, and related active matter research, for improving algal bioprocessing efficiency. Winton Programme for the Physics of Sustainability.

  4. Bioethanol Production from Indigenous Algae

    Directory of Open Access Journals (Sweden)

    Madhuka Roy

    2015-02-01

    Full Text Available Enhanced rate of fossil fuel extraction is likely to deplete limited natural resources over short period of time. So search for alternative fuel is only the way to overcome this problem of upcoming energy crisis. In this aspect biofuel is a sustainable option. Agricultural lands cannot be compromised for biofuel production due to the requirement of food for the increasing population. Certain species of algae can produce ethanol during anaerobic fermentation and thus serve as a direct source for bioethanol production. The high content of complex carbohydrates entrapped in the cell wall of the microalgae makes it essential to incorporate a pre-treatment stage to release and convert these complex carbohydrates into simple sugars prior to the fermentation process. There have been researches on production of bioethanol from a particular species of algae, but this work was an attempt to produce bioethanol from easily available indigenous algae. Acid hydrolysis was carried out as pre-treatment. Gas Chromatographic analysis showed that 5 days’ fermentation by baker’s yeast had yielded 93% pure bioethanol. The fuel characterization of the bioethanol with respect to gasoline showed comparable and quite satisfactory results for its use as an alternative fuel.DOI: http://dx.doi.org/10.3126/ije.v4i1.12182International Journal of Environment Volume-4, Issue-1, Dec-Feb 2014/15, page: 112-120  

  5. Algae-based oral recombinant vaccines

    Directory of Open Access Journals (Sweden)

    Elizabeth A Specht

    2014-02-01

    Full Text Available Recombinant subunit vaccines are some of the safest and most effective vaccines available, but their high cost and the requirement of advanced medical infrastructure for administration make them impractical for many developing world diseases. Plant-based vaccines have shifted that paradigm by paving the way for recombinant vaccine production at agricultural scale using an edible host. However, enthusiasm for molecular pharming in food crops has waned in the last decade due to difficulty in developing transgenic crop plants and concerns of contaminating the food supply. Microalgae are poised to become the next candidate in recombinant subunit vaccine production, and they present several advantages over terrestrial crop plant-based platforms including scalable and contained growth, rapid transformation, easily obtained stable cell lines, and consistent transgene expression levels. Algae have been shown to accumulate and properly fold several vaccine antigens, and efforts are underway to create recombinant algal fusion proteins that can enhance antigenicity for effective orally-delivered vaccines. These approaches have the potential to revolutionize the way subunit vaccines are made and delivered – from costly parenteral administration of purified protein, to an inexpensive oral algae tablet with effective mucosal and system immune reactivity.

  6. Algae-based oral recombinant vaccines

    Science.gov (United States)

    Specht, Elizabeth A.; Mayfield, Stephen P.

    2014-01-01

    Recombinant subunit vaccines are some of the safest and most effective vaccines available, but their high cost and the requirement of advanced medical infrastructure for administration make them impractical for many developing world diseases. Plant-based vaccines have shifted that paradigm by paving the way for recombinant vaccine production at agricultural scale using an edible host. However, enthusiasm for “molecular pharming” in food crops has waned in the last decade due to difficulty in developing transgenic crop plants and concerns of contaminating the food supply. Microalgae could be poised to become the next candidate in recombinant subunit vaccine production, as they present several advantages over terrestrial crop plant-based platforms including scalable and contained growth, rapid transformation, easily obtained stable cell lines, and consistent transgene expression levels. Algae have been shown to accumulate and properly fold several vaccine antigens, and efforts are underway to create recombinant algal fusion proteins that can enhance antigenicity for effective orally delivered vaccines. These approaches have the potential to revolutionize the way subunit vaccines are made and delivered – from costly parenteral administration of purified protein, to an inexpensive oral algae tablet with effective mucosal and systemic immune reactivity. PMID:24596570

  7. Competitive interactions between corals and turf algae depend on coral colony form.

    Science.gov (United States)

    Swierts, Thomas; Vermeij, Mark Ja

    2016-01-01

    Turf algae are becoming more abundant on coral reefs worldwide, but their effects on other benthic organisms remain poorly described. To describe the general characteristics of competitive interactions between corals and turf algae, we determined the occurrence and outcomes of coral-turf algal interactions among different coral growth forms (branching, upright, massive, encrusting, plating, and solitary) on a shallow reef in Vietnam. In total, the amount of turf algal interaction, i.e., the proportion of the coral boundary directly bordering turf algae, was quantified for 1,276 coral colonies belonging to 27 genera and the putative outcome of each interaction was noted. The amount of turf algal interaction and the outcome of these interactions differed predictably among the six growth forms. Encrusting corals interacted most often with turf algae, but also competed most successfully against turf algae. The opposite was observed for branching corals, which rarely interacted with turf algae and rarely won these competitive interactions. Including all other growth forms, a positive relationship was found between the amount of competitive interactions with neighboring turf algae and the percentage of such interaction won by the coral. This growth form dependent ability to outcompete turf algae was not only observed among coral species, but also among different growth forms in morphologically plastic coral genera (Acropora, Favia, Favites, Montastrea, Montipora, Porites) illustrating the general nature of this relationship.

  8. Spatio-temporal patterns of photosystem II activity and plasma-membrane proton flows in Chara corallina cells exposed to overall and local illumination.

    Science.gov (United States)

    Bulychev, Alexander; Vredenberg, Wim

    2003-11-01

    Pulse-amplitude modulated microfluorometry and an extracellular pH microprobe were used to examine light-induced spatial heterogeneity of photosynthetic and H(+)-transporting activities in cells of Chara corallina Klein ex Willd. Subcellular domains featuring different PSII photochemical activities were found to conform to alternate alkaline and acid zones produced near the cell surface, with peaks of PSII activity correlating with the position of acid zones. Buffers eliminated pH variations near the cell surface but did not destroy the variations in PSII photochemical yield (deltaF/Fm'). When a dark-adapted cell was exposed to actinic light, the PSII effective yield decreased within 5-15 min in the alkaline regions but rose after the initial decline in the acid regions. The light-induced decrease in deltaF/Fm' in the alkaline regions occurred prior to or synchronously with the steep rise in local pH. The kinetics of deltaF/Fm', Fm', and F observed in alkaline regions under overall illumination of Chara cells were replaced by those typical of acid regions, when the illumination area size was restricted to 1.5-2 mm. The data show that photoinduced patterns in photosynthetic activity are not predetermined by the particular structural organization of alkaline and acid cell regions but are subject to dynamic changes.

  9. Bacterial Enhancement of Vinyl Fouling by Algae

    OpenAIRE

    Holmes, Paul E.

    1986-01-01

    The role of bacteria in the development of algae on low-density vinyl was investigated. Unidentified bacterial contaminants in unialgal stock cultures of Phormidium faveolarum and Pleurochloris pyrenoidosa enhanced, by 1 to 2 orders of magnitude, colonization of vinyl by these algae, as determined by epifluorescence microscopy counts and chlorophyll a in extracts of colonized vinyl. Colonization by bacteria always preceded that by algae. Scanning electron microscopy of the colonized Phormidiu...

  10. Antioxidant Activity of Hawaiian Marine Algae

    OpenAIRE

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

    2012-01-01

    Marine algae are known to contain a wide variety of bioactive compounds, many of which have commercial applications in pharmaceutical, medical, cosmetic, nutraceutical, food and agricultural industries. Natural antioxidants, found in many algae, are important bioactive compounds that play an important role against various diseases and ageing processes through protection of cells from oxidative damage. In this respect, relatively little is known about the bioactivity of Hawaiian algae that cou...

  11. Stochastic Forecasting of Algae Blooms in Lakes

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-01-15

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

  12. Iron encrustations on filamentous algae colonized by Gallionella-related bacteria in a metal-polluted freshwater stream

    Science.gov (United States)

    Mori, J. F.; Neu, T. R.; Lu, S.; Händel, M.; Totsche, K. U.; Küsel, K.

    2015-09-01

    Filamentous macroscopic algae were observed in slightly acidic to circumneutral (pH 5.9-6.5), metal-rich stream water that leaked out from a former uranium mining district (Ronneburg, Germany). These algae differed in color and morphology and were encrusted with Fe-deposits. To elucidate their potential interaction with Fe(II)-oxidizing bacteria (FeOB), we collected algal samples at three time points during summer 2013 and studied the algae-bacteria-mineral compositions via confocal laser scanning microscopy (CLSM), scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectra, and a 16S and 18S rRNA gene-based bacterial and algae community analysis. Surprisingly, sequencing analysis of 18S rRNA gene regions of green and brown algae revealed high homologies with the freshwater algae Tribonema (99.9-100 %). CLSM imaging indicated a loss of active chloroplasts in the algae cells, which may be responsible for the change in color in oxidation under the putative oxygen-saturated conditions that occur in association with photosynthetic algae. Quantitative PCR (polymerase chain reaction) revealed even higher Gallionella-related 16S rRNA gene copy numbers on the surface of green algae compared to the brown algae. The latter harbored a higher microbial diversity, including some putative predators of algae. A loss of chloroplasts in the brown algae could have led to lower photosynthetic activities and reduced EPS production, which is known to affect predator colonization. Collectively, our results suggest the coexistence of oxygen-generating algae Tribonema sp. and strictly microaerophilic neutrophilic FeOB in a heavy metal-rich environment.

  13. Switchable photosystem-II designer algae for photobiological hydrogen production

    Science.gov (United States)

    Lee, James Weifu

    2010-01-05

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

  14. Evaluation of filamentous green algae as feedstocks for biofuel production.

    Science.gov (United States)

    Zhang, Wei; Zhao, Yonggang; Cui, Binjie; Wang, Hui; Liu, Tianzhong

    2016-11-01

    Compared with unicellular microalgae, filamentous algae have high resistance to grazer-predation and low-cost recovery in large-scale production. Green algae, as the most diverse group of algae, included numerous filamentous genera and species. In this study, records of filamentous genera and species in green algae were firstly censused and classified. Then, seven filamentous strains subordinated in different genera were cultivated in bubbled-column to investigate their growth rate and energy molecular (lipid and starch) capacity. Four strains including Stigeoclonium sp., Oedogonium nodulosum, Hormidium sp. and Zygnema extenue were screened out due to their robust growth. And they all could accumulate triacylglycerols and starch in their biomass, but with different capacity. After nitrogen starvation, Hormidium sp. and Oedogonium nodulosum respectively exhibited high capacity of lipid (45.38% in dry weight) and starch (46.19% in dry weight) accumulation, which could be of high potential as feedstocks for biodiesel and bioethanol production. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Insights into the red algae and eukaryotic evolution from the genome of Porphyra umbilicalis (Bangiophyceae, Rhodophyta).

    Science.gov (United States)

    Brawley, Susan H; Blouin, Nicolas A; Ficko-Blean, Elizabeth; Wheeler, Glen L; Lohr, Martin; Goodson, Holly V; Jenkins, Jerry W; Blaby-Haas, Crysten E; Helliwell, Katherine E; Chan, Cheong Xin; Marriage, Tara N; Bhattacharya, Debashish; Klein, Anita S; Badis, Yacine; Brodie, Juliet; Cao, Yuanyu; Collén, Jonas; Dittami, Simon M; Gachon, Claire M M; Green, Beverley R; Karpowicz, Steven J; Kim, Jay W; Kudahl, Ulrich Johan; Lin, Senjie; Michel, Gurvan; Mittag, Maria; Olson, Bradley J S C; Pangilinan, Jasmyn L; Peng, Yi; Qiu, Huan; Shu, Shengqiang; Singer, John T; Smith, Alison G; Sprecher, Brittany N; Wagner, Volker; Wang, Wenfei; Wang, Zhi-Yong; Yan, Juying; Yarish, Charles; Zäuner-Riek, Simone; Zhuang, Yunyun; Zou, Yong; Lindquist, Erika A; Grimwood, Jane; Barry, Kerrie W; Rokhsar, Daniel S; Schmutz, Jeremy; Stiller, John W; Grossman, Arthur R; Prochnik, Simon E

    2017-08-01

    Porphyra umbilicalis (laver) belongs to an ancient group of red algae (Bangiophyceae), is harvested for human food, and thrives in the harsh conditions of the upper intertidal zone. Here we present the 87.7-Mbp haploid Porphyra genome (65.8% G + C content, 13,125 gene loci) and elucidate traits that inform our understanding of the biology of red algae as one of the few multicellular eukaryotic lineages. Novel features of the Porphyra genome shared by other red algae relate to the cytoskeleton, calcium signaling, the cell cycle, and stress-tolerance mechanisms including photoprotection. Cytoskeletal motor proteins in Porphyra are restricted to a small set of kinesins that appear to be the only universal cytoskeletal motors within the red algae. Dynein motors are absent, and most red algae, including Porphyra , lack myosin. This surprisingly minimal cytoskeleton offers a potential explanation for why red algal cells and multicellular structures are more limited in size than in most multicellular lineages. Additional discoveries further relating to the stress tolerance of bangiophytes include ancestral enzymes for sulfation of the hydrophilic galactan-rich cell wall, evidence for mannan synthesis that originated before the divergence of green and red algae, and a high capacity for nutrient uptake. Our analyses provide a comprehensive understanding of the red algae, which are both commercially important and have played a major role in the evolution of other algal groups through secondary endosymbioses.

  16. Method and apparatus for detecting phycocyanin-pigmented algae and bacteria from reflected light

    Science.gov (United States)

    Vincent, Robert (Inventor)

    2013-01-01

    The present invention relates to a method of detecting phycocyanin algae or bacteria in water from reflected light, and also includes devices for the measurement, calculation and transmission of data relating to that method.

  17. Decreased abundance of crustose coralline algae due to ocean acidification

    Science.gov (United States)

    Kuffner, Ilsa B.; Andersson, Andreas J; Jokiel, Paul L.; Rodgers, Ku'ulei S.; Mackenzie, Fred T.

    2008-01-01

    Owing to anthropogenic emissions, atmospheric concentrations of carbon dioxide could almost double between 2006 and 2100 according to business-as-usual carbon dioxide emission scenarios1. Because the ocean absorbs carbon dioxide from the atmosphere2, 3, 4, increasing atmospheric carbon dioxide concentrations will lead to increasing dissolved inorganic carbon and carbon dioxide in surface ocean waters, and hence acidification and lower carbonate saturation states2, 5. As a consequence, it has been suggested that marine calcifying organisms, for example corals, coralline algae, molluscs and foraminifera, will have difficulties producing their skeletons and shells at current rates6, 7, with potentially severe implications for marine ecosystems, including coral reefs6, 8, 9, 10, 11. Here we report a seven-week experiment exploring the effects of ocean acidification on crustose coralline algae, a cosmopolitan group of calcifying algae that is ecologically important in most shallow-water habitats12, 13, 14. Six outdoor mesocosms were continuously supplied with sea water from the adjacent reef and manipulated to simulate conditions of either ambient or elevated seawater carbon dioxide concentrations. The recruitment rate and growth of crustose coralline algae were severely inhibited in the elevated carbon dioxide mesocosms. Our findings suggest that ocean acidification due to human activities could cause significant change to benthic community structure in shallow-warm-water carbonate ecosystems.

  18. Cultivation of macroscopic marine algae

    Energy Technology Data Exchange (ETDEWEB)

    Ryther, J.H.

    1982-11-01

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

  19. Modeling and optimization of algae growth

    NARCIS (Netherlands)

    Thornton, Anthony Richard; Weinhart, Thomas; Bokhove, Onno; Zhang, Bowen; van der Sar, Dick M.; Kumar, Kundan; Pisarenco, Maxim; Rudnaya, Maria; Savceno, Valeriu; Rademacher, Jens; Zijlstra, Julia; Szabelska, Alicja; Zyprych, Joanna; van der Schans, Martin; Timperio, Vincent; Veerman, Frits; Frank, J.; van der Mei, R.; den Boer, A.; Bosman, J.; Bouman, N.; van Dam, S.; Verhoef, C.

    2010-01-01

    The wastewater from greenhouses has a high amount of mineral contamination and an environmentally-friendly method of removal is to use algae to clean this runo water. The algae consume the minerals as part of their growth process. In addition to cleaning the water, the created algal bio-mass has a

  20. SSMILes: Measuring the Nutrient Tolerance of Algae.

    Science.gov (United States)

    Hedgepeth, David J.

    1995-01-01

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

  1. Modeling and optimization of algae growth

    NARCIS (Netherlands)

    Thornton, Anthony Richard; Weinhart, Thomas; Bokhove, Onno; Zhang, Bowen; van der Sar, Dick M.; Kumar, Kundan; Pisarenco, Maxim; Rudnaya, Maria; Savcenco, Valeriu; Rademacher, Jens; Zijlstra, Julia; Szabelska, Alicja; Zyprych, Joanna; van der Schans, Martin; Timperio, Vincent; Veerman, Frits

    2010-01-01

    The wastewater from greenhouses has a high amount of mineral contamination and an environmentally-friendly method of removal is to use algae to clean this runoff water. The algae consume the minerals as part of their growth process. In addition to cleaning the water, the created algal bio-mass has a

  2. Algae commensal community in Genlisea traps

    Directory of Open Access Journals (Sweden)

    Konrad Wołowski

    2011-01-01

    Full Text Available The community of algae occurring in Genlisea traps and on the external traps surface in laboratory conditions were studied. A total of 29 taxa were found inside the traps, with abundant diatoms, green algae (Chlamydophyceae and four morphotypes of chrysophytes stomatocysts. One morphotype is described as new for science. There are two ways of algae getting into Genlisea traps. The majority of those recorded inside the traps, are mobile; swimming freely by flagella or moving exuding mucilage like diatoms being ablate to colonize the traps themselves. Another possibility is transport of algae by invertebrates such as mites and crustaceans. In any case algae in the Genlisea traps come from the surrounding environment. Two dominant groups of algae (Chladymonas div. and diatoms in the trap environment, show ability to hydrolyze phosphomonoseters. We suggest that algae in carnivorous plant traps can compete with plant (host for organic phosphate (phosphomonoseters. From the spectrum and ecological requirements of algal species found in the traps, environment inside the traps seems to be acidic. However, further studies are needed to test the relations between algae and carnivorous plants both in laboratory conditions and in the natural environment. All the reported taxa are described briefly and documented with 74 LM and SEM micrographs.

  3. Enemy release an unlikely explanation for the invasive potential of the brown alga Sargassum muticum

    DEFF Research Database (Denmark)

    Pedersen, Morten Foldager; Johnsen, Kathrine L.; Halle, Louise L.

    2016-01-01

    included in the comparison. We conducted therefore a series of feeding experiments to test if Danish S. muticum is grazed less upon than a range of native algae by the sea urchin Psammechinus miliaris and complemented the experiments with a meta-analysis based on published data. In no-choice trials, P...... native herbivores feed less on S. muticum relative to native algae within the invaded range. Some of these studies have concluded that S. muticum is avoided by native herbivores, but this conclusion may be premature as the results are rather inconclusive and seem to depend partly on the type of algae...

  4. Advances in genetic engineering of marine algae.

    Science.gov (United States)

    Qin, Song; Lin, Hanzhi; Jiang, Peng

    2012-01-01

    Algae are a component of bait sources for animal aquaculture, and they produce abundant valuable compounds for the chemical industry and human health. With today's fast growing demand for algae biofuels and the profitable market for cosmetics and pharmaceuticals made from algal natural products, the genetic engineering of marine algae has been attracting increasing attention as a crucial systemic technology to address the challenge of the biomass feedstock supply for sustainable industrial applications and to modify the metabolic pathway for the more efficient production of high-value products. Nevertheless, to date, only a few marine algae species can be genetically manipulated. In this article, an updated account of the research progress in marine algal genomics is presented along with methods for transformation. In addition, vector construction and gene selection strategies are reviewed. Meanwhile, a review on the progress of bioreactor technologies for marine algae culture is also revisited. Copyright © 2012 Elsevier Inc. All rights reserved.

  5. Cars will be fed on algae

    International Nuclear Information System (INIS)

    Peltier, G.

    2012-01-01

    The development of the first and second generations of bio-fuels has led to a rise in food prices and the carbon balance sheet is less good than expected. Great hopes have been put on unicellular algae for they can synthesize oils, sugar and even hydrogen and the competition with food production is far less harsh than with actual bio-fuels. Moreover, when you grow micro-algae, the loss of water through evaporation is less important than in the case of intensive farm cultures. In 2009 10.000 tonnes of micro-algae were produced worldwide, they were mainly used for the production of fish food and of complements for humane food (fat acids and antioxidants). Different research programs concern unicellular algae: they aim at modifying micro-algae genetically in order to give them a higher productivity or to make them produce an oil more adapted for motor fuel or more easily recoverable. (A.C.)

  6. Potential biomedical applications of marine algae.

    Science.gov (United States)

    Wang, Hui-Min David; Li, Xiao-Chun; Lee, Duu-Jong; Chang, Jo-Shu

    2017-11-01

    Functional components extracted from algal biomass are widely used as dietary and health supplements with a variety of applications in food science and technology. In contrast, the applications of algae in dermal-related products have received much less attention, despite that algae also possess high potential for the uses in anti-infection, anti-aging, skin-whitening, and skin tumor treatments. This review, therefore, focuses on integrating studies on algae pertinent to human skin care, health and therapy. The active compounds in algae related to human skin treatments are mentioned and the possible mechanisms involved are described. The main purpose of this review is to identify serviceable algae functions in skin treatments to facilitate practical applications in this high-potential area. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Algae viability over time in a ballast water sample

    Science.gov (United States)

    Gollasch, Stephan; David, Matej

    2018-03-01

    The biology of vessels' ballast water needs to be analysed for several reasons, one of these being performance tests of ballast water management systems. This analysis includes a viability assessment of phytoplankton. To overcome logistical problems to get algae sample processing gear on board of a vessel to document algae viability, samples may be transported to land-based laboratories. Concerns were raised how the storage conditions of the sample may impact algae viability over time and what the most appropriate storage conditions were. Here we answer these questions with a long-term algae viability study with daily sample analysis using Pulse-Amplitude Modulated (PAM) fluorometry. The sample was analysed over 79 days. We tested different storage conditions: fridge and room temperature with and without light. It seems that during the first two weeks of the experiment the viability remains almost unchanged with a slight downwards trend. In the continuing period, before the sample was split, a slightly stronger downwards viability trend was observed, which occurred at a similar rate towards the end of the experiment. After the sample was split, the strongest viability reduction was measured for the sample stored without light at room temperature. We concluded that the storage conditions, especially regarding temperature and light exposure, have a stronger impact on algae viability compared to the storage duration and that inappropriate storage conditions reduce algal viability. A sample storage time of up to two weeks in a dark and cool environment has little influence on the organism viability. This indicates that a two week time duration between sample taking on board a vessel and the viability measurement in a land-based laboratory may not be very critical.

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

    Science.gov (United States)

    LeBlanc, Kelly L; Smith, Matthew S; Wallschläger, Dirk

    2012-06-05

    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.

  9. Detection of Chronic Stress in Corals Exposed to Invasive Algae Mats

    Science.gov (United States)

    Sindorf, V.; Richmond, R. H.

    2016-02-01

    Invasive algae mats like those common in Kāne`ohe Bay, O`ahu, are known to negatively affect coral health and recruitment through a variety of mechanisms including shading, abrasion, oxidative stress, and allelopathic interactions. Algae-induced stress has thus far been documented through changes in photosynthetic efficiency and coloration (bleaching) of the coral, and these studies have been largely accomplished through experimental manipulation, inflicting acute stress on coral nubbins. Few studies have investigated the stress response of corals chronically exposed to algae-induced stress, and fewer have used molecular methods to demonstrate and quantify this stress. This study focuses on Porites compressa colonies in chronic contact with the invasive alga Kappaphycus alvarezii on naturally occurring patch reefs in Kāne`ohe Bay, O`ahu, Hawai`i. Our findings demonstrate the ability of these methods to detect and monitor coral stress before outward signs of stress such as bleaching are evident, which will allow for more proactive management of at-risk coral reef ecosystems. The differential expression of genes and gene products (proteins) between corals in long-term contact with invasive algae and those not in contact with algae highlight the specific metabolic pathways involved in algae-induced stress response of corals and lays the foundation for understanding mechanisms of acclimation and resilience towards these stressors.

  10. [Antiapoptotic gene bcl-2 prevents cellular senescence program reactivation induced by histone deacetylase inhibitor sodium butyrate in E1A and cHa-ras transformed rat fibroblasts].

    Science.gov (United States)

    Gordeev, S A; Bykova, T V; Zubova, S G; Aksenov, N D; Pospelova, T V

    2015-01-01

    We have investigated the role of apoptosis resistance gene bcl-2 in the activation of cellular senescence program induced by histone deacetylase inhibitor (HDACi) sodium butyrate (NaBut) in transformed rat fibroblasts. This study was conducted in a resistant to apoptosis induction cell line of rat embryo fibroblasts transfor- med by oncogenes E1A, cHa-ras and bcl-2 (ERasBcl). The parent cell line transformed with only EJA and cHa-ras (ERas) was used as a control. It has been found that NaBut reduces proliferation rate of ERasBcl cells significantly weaker than of ERas transformed cells, despite the fact that the G1 cell cycle arrest was observed in both cell lines. After NaBut treatment, hypertrophy of the apoptosis resistant transformants ERasBcl also was reduced compared to parent cell line ERas, due to less activation of mTORC1, which is known to control the synthesis of protein and ribosome biogenesis. The degree of mTORC1 activation was as.sessed by its target proteins phosphorylation: the ribosomal S6 protein and 4E-BP1--inhibitor of translation initiation factor eIF4E. Since cell senescence process may be associated with changes in autophagy regulation, we analyzed the dynamics of one of the main autophagosome formation markers--protein LC3. The accumulation of lipid-bound form LC3-II changes significantly in ERasBcl cells after NaBut treatment and has transient nature. The set of analyzed cellular senescence markers suggests that a high level of apoptosis resistance gene bcl-2 expression prevents the realization of tumor-suppressor senescence program induced by HDACi sodium butyrate treatment.

  11. Transport and metabolic degradation of hydrogen peroxide in Chara corallina: model calculations and measurements with the pressure probe suggest transport of H(2)O(2) across water channels.

    Science.gov (United States)

    Henzler, T; Steudle, E

    2000-12-01

    A mathematical model is presented that describes permeation of hydrogen peroxide across a cell membrane and the implications of solute decomposition by catalase inside the cell. The model was checked and analysed by means of a numerical calculation that raised predictions for measured osmotic pressure relaxation curves. Predictions were tested with isolated internodal cells of CHARA: corallina, a model system for investigating interactions between water and solute transport in plant cells. Series of biphasic osmotic pressure relaxation curves with different concentrations of H(2)O(2) of up to 350 mol m(-3) are presented. A detailed description of determination of permeability (P(s)) and reflection coefficients (sigma(s)) for H(2)O(2) is given in the presence of the chemical reaction in the cell. Mean values were P(s)=(3.6+/-1.0) 10(-6) m s(-1) and sigma(s)=(0.33+/-0.12) (+/-SD, N=6 cells). Besides transport properties, coefficients for the catalase reaction following a Michaelis-Menten type of kinetics were determined. Mean values of the Michaelis constant (k(M)) and the maximum rate of decompositon (v(max)) were k(M)=(85+/-55) mol m(-3) and v(max)=(49+/-40) nmol (s cell)(-1), respectively. The absolute values of P:(s) and sigma(s) of H(2)O(2) indicated that hydrogen peroxide, a molecule with chemical properties close to that of water, uses water channels (aquaporins) to cross the cell membrane rapidly. When water channels were inhibited with the blocker mercuric chloride (HgCl(2)), the permeabilities of both water and H(2)O(2) were substantially reduced. In fact, for the latter, it was not measurable. It is suggested that some of the water channels in CHARA: (and, perhaps, in other species) serve as 'peroxoporins' rather than as 'aquaporins'.

  12. A near-infrared interferometric survey of debris-disc stars. VI. Extending the exozodiacal light survey with CHARA/JouFLU

    Science.gov (United States)

    Nuñez, P. D.; Scott, N. J.; Mennesson, B.; Absil, O.; Augereau, J.-C.; Bryden, G.; ten Brummelaar, T.; Ertel, S.; Coudé du Foresto, V.; Ridgway, S. T.; Sturmann, J.; Sturmann, L.; Turner, N. J.; Turner, N. H.

    2017-12-01

    We report the results of high-angular-resolution observations that search for exozodiacal light in a sample of main sequence stars and sub-giants. Using the "jouvence" of the fiber linked unit for optical recombination (JouFLU) at the center for high angular resolution astronomy (CHARA) telescope array, we have observed a total of 44 stars. Out of the 44 stars, 33 are new stars added to the initial, previously published survey of 42 stars performed at CHARA with the fiber linked unit for optical recombination (FLUOR). Since the start of the survey extension, we have detected a K-band circumstellar excess for six new stars at the 1% level or higher, four of which are known or candidate binaries, and two for which the excess could be attributed to exozodiacal dust. We have also performed follow-up observations of 11 of the stars observed in the previously published survey and found generally consistent results. We do however detect a significantly larger excess on three of these follow-up targets: Altair, υ And and κ CrB. Interestingly, the last two are known exoplanet host stars. We perform a statistical analysis of the JouFLU and FLUOR samples combined, which yields an overall exozodi detection rate of . We also find that the K-band excess in FGK-type stars correlates with the existence of an outer reservoir of cold (≲100 K) dust at the 99% confidence level, while the same cannot be said for A-type stars.

  13. Inorganic carbon addition stimulates snow algae primary productivity.

    Science.gov (United States)

    Hamilton, Trinity L; Havig, Jeff R

    2018-01-29

    Earth has experienced glacial/interglacial oscillations accompanied by changes in atmospheric CO 2 throughout much of its history. Today over 15 million square kilometers of Earth's land surface is covered in ice including glaciers, ice caps, and ice sheets. Glaciers are teeming with life and supraglacial snow and ice surfaces are often darkened by the presence of photoautotrophic snow algae, resulting in accelerated melt due to lowered albedo. Few studies report the productivity of snow algal communities and the parameters which constrain their growth on supraglacial surfaces-key factors for quantifying biologically induced albedo effects (bio-albedo). We demonstrate that snow algae primary productivity is stimulated by the addition of inorganic carbon. Our results indicate a positive feedback between increasing CO 2 and snow algal primary productivity, underscoring the need for robust climate models of past and present glacial/interglacial oscillations to include feedbacks between supraglacial primary productivity, albedo, and atmospheric CO 2 .

  14. [Value of specific 16S rDNA fragment of algae in diagnosis of drowning: an experiment with rabbits].

    Science.gov (United States)

    Li, Peng; Xu, Qu-Yi; Chen, Ling; Liu, Chao; Zhao, Jian; Wang, Yu-Zhong; Yu, Zheng-Liang; Hu, Sun-Lin; Wang, Hui-Jun

    2015-08-01

    To establish a method for amplifying specific 16S rDNA fragment of algae related with drowning and test its value in drowning diagnosis. Thirty-five rabbits were randomly divided into 3 the drowning group (n=15), postmortem water immersion group (n=15, subjected to air embolism before seawater immersion), and control group(n=5, with air embolism only). Twenty samples of the liver tissues from human corpses found in water were also used, including 14 diatom-positive and 6 diatom-negative samples identified by microwave digestion-vacuum filtration-automated scanning electron microscopy (MD-VF-Auto SEM). Seven known species of algae served as the control algae (Melosira sp, Nitzschia sp, Synedra sp, Navicula sp, Microcystis sp, Cyclotella meneghiniana, and Chlorella sp). The total DNA was extracted from the tissues and algae to amplify the specific fragment of algae followed by 8% polyacrylamide gelelectrophoresis and sliver-staining. In the drowning group, algae was detected in the lungs (100%), liver (86%), and kidney (86%); algae was detected in the lungs in 2 rabbits in the postmortem group (13%) and none in the control group. The positivity rates of algae were significantly higher in the drowning group than in the postmortem group (Palgae, including sample that had been identified as diatom-negative by MD-VF-Auto SEM. All the 7 control algae samples yielded positive results in PCR. The PCR-based method has a high sensitivity in algae detection for drowning diagnosis and allows simultaneous detection of multiple algae species related with drowning.

  15. Errors When Extracting Oil from Algae

    Science.gov (United States)

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

    2014-12-01

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

  16. 21 CFR 73.275 - Dried algae meal.

    Science.gov (United States)

    2010-04-01

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

  17. 21 CFR 73.185 - Haematococcus algae meal.

    Science.gov (United States)

    2010-04-01

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

  18. Algae and UV irradiation: effects on ultrastructure and related metabolic functions.

    Science.gov (United States)

    Holzinger, Andreas; Lütz, Cornelius

    2006-01-01

    The effects of ultraviolet radiation in the biological relevant wavebands of UV-A (315-400 nm) and UV-B (280-315 nm) on algae have become an important issue as a man-made depletion of the protecting ozone layer has been reported. However, experimental designs to investigate this issue are manifold and the target organisms are extremely diverse. Data are included from the prokaryotic cyanobacteria, haptophytes, diatoms, brown algae to green algae (fresh water, snow algae and marine species) including different habitats from marine littoral and open ocean to freshwater ponds, lakes and snow fields. A broad overview on UV effects on algae is given, with a focus on structurally visible changes. Here we report on destruction in chloroplasts, mitochondria, and the occurrence of structures that are likely to be related to the UV stress. In addition several new data are presented from organisms that have to face naturally high UV irradiation due to their habitats. As no disturbances are reported in these organisms, they obviously have a set of protective mechanisms allowing survival in extreme habitats such as snow fields. Physiological changes as a consequence of UV irradiation are included, effects on the DNA level are summarized, and avoidance strategies are discussed. Every effort has been made to summarize the diverse observations and critically evaluate and compare the different experimental strategies to study UV effects in algae.

  19. High efficiency metal removal from hexane-extracted algae oil using super and subcritical propane

    International Nuclear Information System (INIS)

    Machida, Hiroshi; Horizoe, Hirotoshi

    2015-01-01

    Highlights: • Metal removal from algae oil was achieved by supercritical propane solvent extraction. • Continuous metal removing process was developed. • Required energy for metal removing was calculated. - Abstract: As a renewable energy source, oil-producing algae have received much attention in recent years. Raw oil, which is normally extracted from algae using solvents such as hexane or ethyl acetate, includes trace metal compounds that rapidly deactivate the hydrogenation catalyst. In this study, metal removal from hexane-extracted algae oil with supercritical and subcritical propane extraction was examined at temperatures from 40 °C to 130 °C and at 6 MPa pressure. The results showed that the metal concentration became decreasing with temperature increasing and metals were not detectable at 114 °C. Using these results, an energy saving process was proposed. Simulation results showed that the metal removal required a mere 3–4% energy consumption compared to a lower heating value of raw oil

  20. Biodegradation of naproxen by freshwater algae Cymbella sp. and Scenedesmus quadricauda and the comparative toxicity.

    Science.gov (United States)

    Ding, Tengda; Lin, Kunde; Yang, Bo; Yang, Mengting; Li, Juying; Li, Wenying; Gan, Jay

    2017-08-01

    Naproxen is one of the most prevalent pharmaceuticals and of great environment concern. Information about bioremediation of naproxen by algae remains limited and no study has been reported on the degradation mechanism and the toxicity of NPX on algae. In this study, both Cymbella sp. and Scenedesmus quadricauda showed complete growth inhibition (100%) at 100mgL -1 within 24h. Biochemical characteristics including chlorophyll a, carotenoid contents and enzyme activities for these two microalgae were affected by NPX at relatively high concentrations after 4d of exposure. Degradation of naproxen was accelerated by both algae species. Cymbella sp. showed a more satisfactive effect in the bioremediation of NPX with higher removal efficiency. A total of 12 metabolites were identified by LC-MS/MS and the degradation pathways of naproxen in two algae were proposed. Hydroxylation, decarboxylation, demethylation, tyrosine conjunction and glucuronidation contributed to naproxen transformation in algal cells. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Design and installation of a strategically placed algae mesh barrier at OPG Pickering Nuclear Generating Station

    International Nuclear Information System (INIS)

    Marttila, D.; Patrick, P.; Gregoris, C.

    2009-01-01

    Ontario Power Generation's Pickering Nuclear has experienced a number of events in which attached algae have become entrained in the water intake costing approximately $30M over the 1995-2005 period as a result of deratings, Unit shutdowns and other operational issues. In 2005-2006 OPG and Kinectrics worked collaboratively on evaluating different potential solutions to reduce the impact of algae on the station. One of the solutions developed by Kinectrics included a strategically placed barrier net designed to regulate algae flow into the station intake. In 2006, Kinectrics designed and installed the system, the first of its kind at a Nuclear Power Plant in Canada. The system was operational by May 2007. OPG completed an effectiveness study in 2007 and concluded the barrier system had a beneficial effect on reducing algae impact on the station. (author)

  2. Algunos aspectos de la variabilidad de los oogonios en poblaciones actuales del género Chara (Charophyceae. Aplicación paleontológica

    Directory of Open Access Journals (Sweden)

    Pedrola, J.

    1986-10-01

    Full Text Available A critical revision of some useful taxonomic criteria in paleontology of Charophytes is carried Out. The results are based in four modern populations ((Chara aculeolata, Chara aff.baltica, Chara delicatula and Chara globularis and they permit to make some serious objections to these critera. The results are related with three principal aspects: the meaning of the absolute magnitudes of me girogonite, the behaviour of his joint variation and the morphological variability during the calcification process. In general, and for each one of the four populations, an absence of influence of the position of the girogonite over their measurements is observed. This doesn't happens when the verticil is considered as source of variation. These biometrical differences which are equivalent to some of those that has been used to distinguish fossil species, are not due to a process of progressive or heteregenous calcification in the secuence of verticils of me plant. Several arguments against the indiscriminate use of cocients between absolute magnitudes (e.g. the polarity index as detectors of systematic interest are showed. In the same way, some remarks to the use of the morphology of the spiral calcificated cells, the prominence of the basal pore and some aspects of the apex shape, as taxonomic criteria are made. All this are variable within the same plant when there are differents in the calcification degree of the girogonites.

    Se hace una revisión crítica de-algunos criterios taxonómicos de uso habitual en paleontología de carofitas. Sus resultados, basados en cuatro poblaciones actuales (Chara aculeolata, Chara aff.baltica, Chara delicatula y Chara globularis, permiten hacer algunas serias objeciones a estos criterios. Dichos resultados se relacionan con tres aspectos principales: el significado de las magnitudes absolutas del girogonito, el comportamiento de su variación conjunta y la variabilidad

  3. The Biology of blue-green algae

    National Research Council Canada - National Science Library

    Carr, Nicholas G; Whitton, B. A

    1973-01-01

    .... Their important environmental roles, their part in nitrogen fixation and the biochemistry of phototrophic metabolism are some of the attractions of blue-geen algae to an increasing number of biologists...

  4. Collection, Isolation and Culture of Marine Algae.

    Science.gov (United States)

    James, Daniel E.

    1984-01-01

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

  5. 2011 Biomass Program Platform Peer Review: Algae

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Joyce [Office of Energy Efficiency and Renewable Energy (EERE), Washington, DC (United States)

    2012-02-01

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

  6. Dipeptides from the red alga Acanthopora spicifera

    Digital Repository Service at National Institute of Oceanography (India)

    Wahidullah, S; De; Kamat, S

    An investigation of red alga Acanthophora spicifera afforded the known peptide, aurantiamide acetate and a new diastereoisomer of this dipeptide (dia-aurantiamide acetate). This is a first report of aurantiamide acetate from a marine source...

  7. Marine Polysaccharides from Algae with Potential Biomedical Applications

    Science.gov (United States)

    de Jesus Raposo, Maria Filomena; de Morais, Alcina Maria Bernardo; de Morais, Rui Manuel Santos Costa

    2015-01-01

    There is a current tendency towards bioactive natural products with applications in various industries, such as pharmaceutical, biomedical, cosmetics and food. This has put some emphasis in research on marine organisms, including macroalgae and microalgae, among others. Polysaccharides with marine origin constitute one type of these biochemical compounds that have already proved to have several important properties, such as anticoagulant and/or antithrombotic, immunomodulatory ability, antitumor and cancer preventive, antilipidaemic and hypoglycaemic, antibiotics and anti-inflammatory and antioxidant, making them promising bioactive products and biomaterials with a wide range of applications. Their properties are mainly due to their structure and physicochemical characteristics, which depend on the organism they are produced by. In the biomedical field, the polysaccharides from algae can be used in controlled drug delivery, wound management, and regenerative medicine. This review will focus on the biomedical applications of marine polysaccharides from algae. PMID:25988519

  8. Marine polysaccharides from algae with potential biomedical applications.

    Science.gov (United States)

    de Jesus Raposo, Maria Filomena; de Morais, Alcina Maria Bernardo; de Morais, Rui Manuel Santos Costa

    2015-05-15

    There is a current tendency towards bioactive natural products with applications in various industries, such as pharmaceutical, biomedical, cosmetics and food. This has put some emphasis in research on marine organisms, including macroalgae and microalgae, among others. Polysaccharides with marine origin constitute one type of these biochemical compounds that have already proved to have several important properties, such as anticoagulant and/or antithrombotic, immunomodulatory ability, antitumor and cancer preventive, antilipidaemic and hypoglycaemic, antibiotics and anti-inflammatory and antioxidant, making them promising bioactive products and biomaterials with a wide range of applications. Their properties are mainly due to their structure and physicochemical characteristics, which depend on the organism they are produced by. In the biomedical field, the polysaccharides from algae can be used in controlled drug delivery, wound management, and regenerative medicine. This review will focus on the biomedical applications of marine polysaccharides from algae.

  9. Marine Polysaccharides from Algae with Potential Biomedical Applications

    Directory of Open Access Journals (Sweden)

    Maria Filomena de Jesus Raposo

    2015-05-01

    Full Text Available There is a current tendency towards bioactive natural products with applications in various industries, such as pharmaceutical, biomedical, cosmetics and food. This has put some emphasis in research on marine organisms, including macroalgae and microalgae, among others. Polysaccharides with marine origin constitute one type of these biochemical compounds that have already proved to have several important properties, such as anticoagulant and/or antithrombotic, immunomodulatory ability, antitumor and cancer preventive, antilipidaemic and hypoglycaemic, antibiotics and anti-inflammatory and antioxidant, making them promising bioactive products and biomaterials with a wide range of applications. Their properties are mainly due to their structure and physicochemical characteristics, which depend on the organism they are produced by. In the biomedical field, the polysaccharides from algae can be used in controlled drug delivery, wound management, and regenerative medicine. This review will focus on the biomedical applications of marine polysaccharides from algae.

  10. The cell walls of green algae: a journey through evolution and diversity

    Directory of Open Access Journals (Sweden)

    David eDomozych

    2012-05-01

    Full Text Available The green algae represent a large group of morphologically diverse photosynthetic eukaryotes that occupy virtually every photic habitat on the planet. The extracellular coverings of green algae including cell walls are also diverse. A recent surge of research in green algal cell walls fueled by new emerging technologies has revealed new and critical insight concerning these coverings. For example, the late divergent taxa of the Charophycean Green Algae possess cell walls containing assemblages of polymers with notable similarity to the cellulose, pectins, hemicelluloses, arabinogalactan proteins, extensin and lignin present in embryophyte walls. Ulvophycean seaweeds have cell wall components whose most abundant fibrillar constituents may change from cellulose to β-mannans to β-xylans and during different life cycle phases. Likewise, these algae produce complex sulfated polysaccharides, arabinogalactan proteins and extensin. Chlorophycean green algae produce a wide array of walls ranging from cellulose-pectin complexes to ones made of hydroxyproline-rich glycoproteins. Larger and more detailed surveys of the green algal taxa including incorporation of emerging genomic and transcriptomic data are required in order to more fully resolve evolutionary trends within the green algae and in relationship with higher plants as well as potential applications of wall components in the food and pharmaceutical industries.

  11. The Cell Walls of Green Algae: A Journey through Evolution and Diversity.

    Science.gov (United States)

    Domozych, David S; Ciancia, Marina; Fangel, Jonatan U; Mikkelsen, Maria Dalgaard; Ulvskov, Peter; Willats, William G T

    2012-01-01

    The green algae represent a large group of morphologically diverse photosynthetic eukaryotes that occupy virtually every photic habitat on the planet. The extracellular coverings of green algae including cell walls are also diverse. A recent surge of research in green algal cell walls fueled by new emerging technologies has revealed new and critical insight concerning these coverings. For example, the late divergent taxa of the Charophycean green algae possess cell walls containing assemblages of polymers with notable similarity to the cellulose, pectins, hemicelluloses, arabinogalactan proteins (AGPs), extensin, and lignin present in embryophyte walls. Ulvophycean seaweeds have cell wall components whose most abundant fibrillar constituents may change from cellulose to β-mannans to β-xylans and during different life cycle phases. Likewise, these algae produce complex sulfated polysaccharides, AGPs, and extensin. Chlorophycean green algae produce a wide array of walls ranging from cellulose-pectin complexes to ones made of hydroxyproline-rich glycoproteins. Larger and more detailed surveys of the green algal taxa including incorporation of emerging genomic and transcriptomic data are required in order to more fully resolve evolutionary trends within the green algae and in relationship with higher plants as well as potential applications of wall components in the food and pharmaceutical industries.

  12. Stochastic Forecasting of Algae Blooms in Lakes

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-01-03

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

  13. Microbial diversity associated with four functional groups of benthic reef algae and the reef-building coral Montastraea annularis.

    Science.gov (United States)

    Barott, Katie L; Rodriguez-Brito, Beltran; Janouškovec, Jan; Marhaver, Kristen L; Smith, Jennifer E; Keeling, Patrick; Rohwer, Forest L

    2011-05-01

    The coral reef benthos is primarily colonized by corals and algae, which are often in direct competition with one another for space. Numerous studies have shown that coral-associated Bacteria are different from the surrounding seawater and are at least partially species specific (i.e. the same bacterial species on the same coral species). Here we extend these microbial studies to four of the major ecological functional groups of algae found on coral reefs: upright and encrusting calcifying algae, fleshy algae, and turf algae, and compare the results to the communities found on the reef-building coral Montastraea annularis. It was found using 16S rDNA tag pyrosequencing that the different algal genera harbour characteristic bacterial communities, and these communities were generally more diverse than those found on corals. While the majority of coral-associated Bacteria were related to known heterotrophs, primarily consuming carbon-rich coral mucus, algal-associated communities harboured a high percentage of autotrophs. The majority of algal-associated autotrophic Bacteria were Cyanobacteria and may be important for nitrogen cycling on the algae. There was also a rich diversity of photosynthetic eukaryotes associated with the algae, including protists, diatoms, and other groups of microalgae. Together, these observations support the hypothesis that coral reefs are a vast landscape of distinctive microbial communities and extend the holobiont concept to benthic algae. © 2011 Society for Applied Microbiology and Blackwell Publishing Ltd.

  14. Behavioural and physical effects of arsenic exposure in fish are aggravated by aquatic algae.

    Science.gov (United States)

    Magellan, Kit; Barral-Fraga, Laura; Rovira, Marona; Srean, Pao; Urrea, Gemma; García-Berthou, Emili; Guasch, Helena

    2014-11-01

    Arsenic contamination has global impacts and freshwaters are major arsenic repositories. Arsenic toxicity depends on numerous interacting factors which makes effects difficult to estimate. The use of aquatic algae is often advocated for bioremediation of arsenic contaminated waters as they absorb arsenate and transform it into arsenite and methylated chemical species. Fish are another key constituent of aquatic ecosystems. Contamination in natural systems is often too low to cause mortality but sufficient to interfere with normal functioning. Alteration of complex, naturally occurring fish behaviours such as foraging and aggression are ecologically relevant indicators of toxicity and ideal for assessing sublethal impacts. We examined the effects of arsenic exposure in the invasive mosquitofish, Gambusia holbrooki, in a laboratory experiment incorporating some of the complexity of natural systems by including the interacting effects of aquatic algae. Our aims were to quantify the effects of arsenic on some complex behaviours and physical parameters in mosquitofish, and to assess whether the detoxifying mechanisms of algae would ameliorate any effects of arsenic exposure. Aggression increased significantly with arsenic whereas operculum movement decreased non-significantly and neither food capture efficiency nor consumption were notably affected. Bioaccumulation increased with arsenic and unexpectedly so did fish biomass. Possibly increased aggression facilitated food resource defence allowing fish to gain weight. The presence of algae aggravated the effects of arsenic exposure. For increase in fish biomass, algae acted antagonistically with arsenic, resulting in a disadvantageous reduction in weight gained. For bioaccumulation the effects were even more severe, as algae operated additively with arsenic to increase arsenic uptake and/or assimilation. Aggression was also highest in the presence of both algae and arsenic. Bioremediation of arsenic contaminated waters

  15. PIXE application for measurement of bioaccumulation of lead by marine micro-algae

    International Nuclear Information System (INIS)

    Iwata, Y.; Suzuki, M.

    2000-01-01

    Marine micro-algae (Nannochloropsis sp., and Phaeodactylum sp.,) were obtained from the Pacific Ocean of Iwate Pref., Japan and purely cultured in nutritive seawater as a culture solution. The culture size for algae was 10-250 ml and every apparatus was small and of low cost. Marine micro-algae were given in different culture solutions including Pb 2+ from 0.01 to 1.0 mg/l. The algae in 5 ml of the culture solution were collected on a polycarbonate filter (pore size: 1.0 μm) by suction filtration. The algae on the filter were subjected to PIXE analysis. Concentrations of Na, Mg, Si, P, S, Cl, K, Ca, Cr, Mn, Fe, Cu, Zn, Sr and Pb were simultaneously determined. PIXE can do multi-element analysis for a sample of below 1 mg. The quantity of lead in marine micro-algae increases in proportion to the Pb 2+ concentration in the culture solution. The concentration factor (wet weight base) for lead is given as 200±20 ml/g for Nannochloropsis sp. and 1900±400 ml/g for Phaeodactylum sp.. It is shown that PIXE is a powerful tool for the measurement of the bioaccumulation of trace elements. (author)

  16. The Selective Use of Hypochlorite to Prevent Pond Crashes for Algae-Biofuel Production.

    Science.gov (United States)

    2015-09-21

    Although algae-biofuels have many advantages including high areal productivity, algae can be preyed upon by amoebas, protozoans, ciliates, and rotifers, particularly in open pond systems. Thus, these higher organisms need to be controlled. In this study, Chlorella kessleri was used as the algal culture and Brachionus calyciflorus as the source of predation. The effect of sodium hypochlorite (bleach) was tested with the goal of totally inhibiting the rotifer while causing minor inhibition to the alga. The 24-hr LC50 for B. calyciflorus in spring water was 0.198 mg Cl/L while the 24-hr LC50 for C. kessleri was 0.321 mg Cl/L. However, chlorine dissipates rapidly as the algae serves as reductant. Results showed a chlorine dosage between 0.45 to 0.6 mg Cl/L and a dosing interval of two hours created the necessary chlorine concentrations to inhibit predation while letting the algae grow; thus giving algae farmers a tool to prevent pond crashes. Water Environ. Res., 87 (2015).

  17. FRESH-WATER GREEN ALGAE (CHLOROPHYTA AS A NATURAL PIGMENT FOR MOJOSARI DUCKS

    Directory of Open Access Journals (Sweden)

    B. Indarsih

    2015-09-01

    Full Text Available An experiment in a completely randomize design was undertaken to study the use of fresh-watergreen algae as a yolk coloring agent in Mojosari ducks during a laying period on productiveperformance and egg quality from 36 to 44 wk of age. A total of 80 thirty-six wk–old laying ducks weredivided into four dietary treatments and each of four replicates with 5 birds. Diets were formulated witha commercial concentrate, rice bran and yellow corn (2:4:4 according to a commercial standard diet asa control, and three other dietary treatments with 2, 4 or 8% of green algae were included. Fresh watergreen algae had a significant effect on the feed uptake, egg production, and feed conversion ratio (FCR(p<0.05. Egg production and FCR improved at added 2 and 4% green algae. No differences wereobserved in egg yolk index, albumen index, Haugh Unit, and egg shell thickness (P>0.05 except eggyolk color. The yolk color increased within 7 days after feeding with the test diets. The present studyindicated that fresh-water green algae could be used as a natural coloring agent in laying ducks and at8% of green algae showed the highest score of (Roche Yellow Color-15.

  18. Multicellularity in green algae: Upsizing in a walled complex.

    Directory of Open Access Journals (Sweden)

    David S. Domozych

    2014-11-01

    Full Text Available Modern green algae constitute a large and diverse taxonomic assemblage that encompasses many multicellular phenotypes including colonial, filamentous and parenchymatous forms. In all multicellular green algae, each cell is surrounded by an extracellular matrix, most often in the form of a cell wall. Volvocalean taxa like Volvox have an elaborate, gel-like, hydroxyproline rich glycoprotein covering that contains the cells of the colony. In ulvophytes, uronic acid-rich and sulfated polysaccharides are the likely adhesion agents that maintain the multicellular habit. Charophytes also produce polysaccharide-rich cell walls and in late divergent taxa, pectin plays a critical role in cell-adhesion in the multicellular complex. Cell walls are products of coordinated interaction of membrane trafficking, cytoskeletal dynamics and the cell’s signal transduction machinery responding both to precise internal clocks and external environmental cues. Most often, these activities must be synchronized with the secretion, deposition and remodeling of the polymers of the extracellular matrix. Rapid advances in molecular genetics, cell biology and cell wall biochemistry of green algae will soon provide new insights into the evolution and subcellular processes leading to multicellularity.

  19. Multicellularity in green algae: upsizing in a walled complex.

    Science.gov (United States)

    Domozych, David S; Domozych, Catherine E

    2014-01-01

    Modern green algae constitute a large and diverse taxonomic assemblage that encompasses many multicellular phenotypes including colonial, filamentous, and parenchymatous forms. In all multicellular green algae, each cell is surrounded by an extracellular matrix (ECM), most often in the form of a cell wall. Volvocalean taxa like Volvox have an elaborate, gel-like, hydroxyproline rich glycoprotein covering that contains the cells of the colony. In "ulvophytes," uronic acid-rich and sulfated polysaccharides are the likely adhesion agents that maintain the multicellular habit. Charophytes also produce polysaccharide-rich cell walls and in late divergent taxa, pectin plays a critical role in cell adhesion in the multicellular complex. Cell walls are products of coordinated interaction of membrane trafficking, cytoskeletal dynamics and the cell's signal transduction machinery responding both to precise internal clocks and external environmental cues. Most often, these activities must be synchronized with the secretion, deposition and remodeling of the polymers of the ECM. Rapid advances in molecular genetics, cell biology and cell wall biochemistry of green algae will soon provide new insights into the evolution and subcellular processes leading to multicellularity.

  20. Extraction, Purification, and NMR Analysis of Terpenes from Brown Algae.

    Science.gov (United States)

    Gaysinski, Marc; Ortalo-Magné, Annick; Thomas, Olivier P; Culioli, Gérald

    2015-01-01

    Algal terpenes constitute a wide and well-documented group of marine natural products with structures differing from their terrestrial plant biosynthetic analogues. Amongst macroalgae, brown seaweeds are considered as one of the richest source of biologically and ecologically relevant terpenoids. These metabolites, mostly encountered in algae of the class Phaeophyceae, are mainly diterpenes and meroditerpenes (metabolites of mixed biogenesis characterized by a toluquinol or a toluquinone nucleus linked to a diterpene moiety).In this chapter, we describe analytical processes commonly employed for the isolation and structural characterization of the main terpenoid constituents obtained from organic extracts of brown algae. The successive steps include (1) extraction of lipidic content from algal samples; (2) purification of terpenes by column chromatography and semi-preparative high-performance liquid chromatography; and (3) structure elucidation of the isolated terpenes by means of 1D and 2D nuclear magnetic resonance (NMR). More precisely, we propose a representative methodology which allows the isolation and structural determination of the monocyclic meroditerpene methoxybifurcarenone (MBFC) from the Mediterranean brown alga Cystoseira amentacea var. stricta. This methodology has a large field of applications and can then be extended to terpenes isolated from other species of the family Sargassaceae.

  1. Towards tradable permits for filamentous green algae pollution.

    Science.gov (United States)

    de Lange, W J; Botha, A M; Oberholster, P J

    2016-09-01

    Water pollution permit systems are challenging to design and implement. Operational systems that has maintained functionality remains few and far between, particularly in developing countries. We present current progress towards developing such a system for nutrient enrichment based water pollution, mainly from commercial agriculture. We applied a production function approach to first estimate the monetary value of the impact of the pollution, which is then used as reference point for establishing a reserve price for pollution permits. The subsequent market making process is explained according to five steps including permit design, terms, conditions and transactional protocol, the monitoring system, piloting and implementation. The monetary value of the impact of pollution was estimated at R1887 per hectare per year, which not only provide a "management budget" for filamentous green algae mitigation strategies in the study area, but also enabled the calculation of a reserve price for filamentous green algae pollution permits, which was estimated between R2.25 and R111 per gram filamentous algae and R8.99 per gram at the preferred state. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

    Science.gov (United States)

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

    2016-01-01

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

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

    Science.gov (United States)

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

    2016-09-01

    Snow algae and green algae living in aeroterrestrial habitats are ideal objects to study adaptation to high light irradiation. Here, we used a detailed description of the spectral properties as a proxy for photo-acclimation/protection in snow algae (Chlamydomonas nivalis, Chlainomonas sp. and Chloromonas sp.) and charophyte green algae (Zygnema sp., Zygogonium ericetorum and Klebsormidium crenulatum). The hyperspectral microscopic mapping and imaging technique allowed us to acquire total absorption spectra of these microalgae in the waveband of 400-900nm. Particularly in Chlamydomonas nivalis and Chlainomonas sp., a high absorbance between 400-550nm was observed, due to naturally occurring secondary carotenoids; in Chloromonas sp. and in the charopyhte algae this high absorbance was missing, the latter being close relatives to land plants. To investigate if cellular water loss has an influence on the spectral properties, the cells were plasmolysed in sorbitol or desiccated at ambient air. While in snow algae, these treatments did hardly change the spectral properties, in the charopyhte algae the condensation of the cytoplasm and plastids increased the absorbance in the lower waveband of 400-500nm. These changes might be ecologically relevant and photoprotective, as aeroterrestrial algae are naturally exposed to occasional water limitation, leading to desiccation, which are conditions usually occurring together with higher irradiation. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  4. Ecological assessments with algae: a review and synthesis.

    Science.gov (United States)

    Stevenson, Jan

    2014-06-01

    Algae have been used for a century in environmental assessments of water bodies and are now used in countries around the world. This review synthesizes recent advances in the field around a framework for environmental assessment and management that can guide design of assessments, applications of phycology in assessments, and refinements of those applications to better support management decisions. Algae are critical parts of aquatic ecosystems that power food webs and biogeochemical cycling. Algae are also major sources of problems that threaten many ecosystems goods and services when abundances of nuisance and toxic taxa are high. Thus, algae can be used to indicate ecosystem goods and services, which complements how algal indicators are also used to assess levels of contaminants and habitat alterations (stressors). Understanding environmental managers' use of algal ecology, taxonomy, and physiology can guide our research and improve its application. Environmental assessments involve characterizing ecological condition and diagnosing causes and threats to ecosystems goods and services. Recent advances in characterizing condition include site-specific models that account for natural variability among habitats to better estimate effects of humans. Relationships between algal assemblages and stressors caused by humans help diagnose stressors and establish targets for protection and restoration. Many algal responses to stressors have thresholds that are particularly important for developing stakeholder consensus for stressor management targets. Future research on the regional-scale resilience of algal assemblages, the ecosystem goods and services they provide, and methods for monitoring and forecasting change will improve water resource management. © 2014 The Authors. Journal of Phycology published by Wiley Periodicals, Inc. on behalf of Phycological Society of America.

  5. Radiation sterilization of harmful algae in water

    International Nuclear Information System (INIS)

    Byung Chull An; Jae-Sung Kim; Seung Sik Lee; Shyamkumar Barampuram; Eun Mi Lee; Byung Yeoup Chung

    2007-01-01

    Complete text of publication follows. Objective: Drinking water, water used in food production and for irrigation, water for fish farming, waste water, surface water, and recreational water have been recently recognized as a vector for the transmission of harmful micro-organisms. The human and animal harmful algae is a waterborne risk to public health and economy because the algae are ubiquitous and persistent in water and wastewater, not completely removed by physical-chemical treatment processes, and relatively resistant to chemical disinfection. Gamma and electron beam radiation technology is of growing in the water industry since it was demonstrated that gamma and electron beam radiation is very effective against harmful algae. Materials and Methods: Harmful algae (Scenedesmus quadricauda(Turpin) Brebisson 1835 (AG10003), Chlorella vulgaris Beijerinck 1896 (AG30007) and Chlamydomonas sp. (AG10061)) were distributed from Korean collection for type cultures (KCTC). Strains were cultured aerobically in Allen's medium at 25□ and 300 umol/m2s for 1 week using bioreactor. We investigated the disinfection efficiency of harmful algae irradiated with gamma (0.05 to 10 kGy for 30 min) and electron beam (1 to 19 kGy for 5 sec) rays. Results and Conclusion: We investigated the disinfection efficiency of harmful algae irradiated with gamma and electron beam rays of 50 to 19000 Gy. We established the optimum sterilization condition which use the gamma and electron beam radiation. Gamma ray disinfected harmful algae at 400 Gy for 30 min. Also, electron beam disinfected at 1000 Gy for 5 sec. This alternative disinfection practice had powerful disinfection efficiency. Hence, the multi-barrier approach for drinking water treatment in which a combination of various disinfectants and filtration technologies are applied for removal and inactivation of different microbial pathogens will guarantee a lower risk of microbial contamination.

  6. Algae Biofuel in the Nigerian Energy Context

    Directory of Open Access Journals (Sweden)

    Elegbede Isa

    2016-05-01

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

  7. Coccolithophorid algae culture in closed photobioreactors.

    Science.gov (United States)

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

    2011-09-01

    The feasibility of growth, calcium carbonate and lipid production of the coccolithophorid algae (Prymnesiophyceae), Pleurochrysis carterae, Emiliania huxleyi, and Gephyrocapsa oceanica, was investigated in plate, carboy, airlift, and tubular photobioreactors. The plate photobioreactor was the most promising closed cultivation system. All species could be grown in the carboy photobioreactor. However, P. carterae was the only species which grew in an airlift photobioreactor. Despite several attempts to grow these coccolithophorid species in the tubular photobioreactor (Biocoil), including modification of the airlift and sparger design, no net growth could be achieved. The shear produced by turbulence and bubble effects are the most likely reasons for this failure to grow in the Biocoil. The highest total dry weight, lipid and calcium carbonate productivities achieved by P. carterae in the plate photobioreactors were 0.54, 0.12, and 0.06 g L(-1) day(-1) respectively. Irrespective of the type of photobioreactor, the productivities were P. carterae > E. huxleyi > G. oceanica. Pleurochrysis carterae lipid (20-25% of dry weight) and calcium carbonate (11-12% of dry weight) contents were also the highest of all species tested. Copyright © 2011 Wiley Periodicals, Inc.

  8. Bioavailability of mineral-bound iron to a snow algae-bacteria co-culture and implications for albedo-altering snow algae blooms.

    Science.gov (United States)

    Harrold, Z R; Hausrath, E M; Garcia, A H; Murray, A E; Tschauner, O; Raymond, J; Huang, S

    2018-01-26

    Snow algae can form large-scale blooms across the snowpack surface and near-surface environments. These pigmented blooms can decrease snow albedo, increase local melt rates, and may impact the global heat budget and water cycle. Yet, underlying causes for the geospatial occurrence of these blooms remain unconstrained. One possible factor contributing to snow algae blooms is the presence of mineral dust as a micronutrient source. We investigated the bioavailability of iron (Fe) -bearing minerals, including forsterite (Fo 90 , Mg 1.8 Fe 0.2 SiO 4 ), goethite, smectite and pyrite as Fe sources for a Chloromonas brevispina - bacteria co-culture through laboratory-based experimentation. Fo 90 was capable of stimulating snow algal growth and increased the algal growth rate in otherwise Fe-depleted co-cultures. Fo 90 -bearing systems also exhibited a decrease in bacteria:algae ratios compared to Fe-depleted conditions, suggesting a shift in microbial community structure. The C. brevispina co-culture also increased the rate of Fo 90 dissolution relative to an abiotic control. Analysis of 16S rRNA genes in the co-culture identified Gammaproteobacteria , Betaprotoeobacteria and Sphingobacteria , all of which are commonly found in snow and ice environments. Archaea were not detected. Collimonas and Pseudomonas , which are known to enhance mineral weathering rates, comprised two of the top eight (> 1 %) OTUs. These data provide unequivocal evidence that mineral dust can support elevated snow algae growth under otherwise Fe-depleted growth conditions, and that snow algae can enhance mineral dissolution under these conditions. IMPORTANCE Fe, a key micronutrient for photosynthetic growth, is necessary to support the formation of high-density snow algae blooms. The laboratory experiments described herein allow for a systematic investigation of snow algae-bacteria-mineral interactions and their ability to mobilize and uptake mineral-bound Fe. Results provide unequivocal and

  9. Sustainable Algae Biodiesel Production in Cold Climates

    Directory of Open Access Journals (Sweden)

    Rudras Baliga

    2010-01-01

    Full Text Available This life cycle assessment aims to determine the most suitable operating conditions for algae biodiesel production in cold climates to minimize energy consumption and environmental impacts. Two hypothetical photobioreactor algae production and biodiesel plants located in Upstate New York (USA are modeled. The photobioreactor is assumed to be housed within a greenhouse that is located adjacent to a fossil fuel or biomass power plant that can supply waste heat and flue gas containing CO2 as a primary source of carbon. Model results show that the biodiesel areal productivity is high (19 to 25 L of BD/m2/yr. The total life cycle energy consumption was between 15 and 23 MJ/L of algae BD and 20 MJ/L of soy BD. Energy consumption and air emissions for algae biodiesel are substantially lower than soy biodiesel when waste heat was utilized. Algae's most substantial contribution is a significant decrease in the petroleum consumed to make the fuel.

  10. Biological toxicity of lanthanide elements on algae.

    Science.gov (United States)

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

    2010-08-01

    The biological toxicity of lanthanides on marine monocellular algae was investigated. The specific objective of this research was to establish the relationship between the abundance in the seawater of lanthanides and their biological toxicities on marine monocellular algae. The results showed that all single lanthanides had similar toxic effects on Skeletonema costatum. High concentrations of lanthanides (29.04+/-0.61 micromol L(-1)) resulted in 50% reduction in growth of algae compared to the controls (0 micromol L(-1)) after 96 h (96 h-EC50). The biological toxicity of 13 lanthanides on marine monocellular algae was unrelated with the abundance of different lanthanide elements in nature, and the "Harkins rule" was not appropriate for the lanthanides. A mixed solution that contained equivalent concentrations of each lanthanide element had the same inhibition effect on algae cells as each individual lanthanide element at the same total concentration. This phenomenon is unique compared to the groups of other elements in the periodic table. Hence, we speculate that the monocellular organisms might not be able to sufficiently differentiate between the almost chemically identical lanthanide elements. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  11. Phospholipids of New Zealand Edible Brown Algae.

    Science.gov (United States)

    Vyssotski, Mikhail; Lagutin, Kirill; MacKenzie, Andrew; Mitchell, Kevin; Scott, Dawn

    2017-07-01

    Edible brown algae have attracted interest as a source of beneficial allenic carotenoid fucoxanthin, and glyco- and phospholipids enriched in polyunsaturated fatty acids. Unlike green algae, brown algae contain no or little phosphatidylserine, possessing an unusual aminophospholipid, phosphatidyl-O-[N-(2-hydroxyethyl) glycine], PHEG, instead. When our routinely used technique of 31 P-NMR analysis of phospholipids was applied to the samples of edible New Zealand brown algae, a number of signals corresponding to unidentified phosphorus-containing compounds were observed in total lipids. NI (negative ion) ESI QToF MS spectra confirmed the presence of more familiar phospholipids, and also suggested the presence of PHEG or its isomers. The structure of PHEG was confirmed by comparison with a synthetic standard. An unusual MS fragmentation pattern that was also observed prompted us to synthesise a number of possible candidates, and was found to follow that of phosphatidylhydroxyethyl methylcarbamate, likely an extraction artefact. An unexpected outcome was the finding of ceramidephosphoinositol that has not been reported previously as occurring in brown algae. An uncommon arsenic-containing phospholipid has also been observed and quantified, and its TLC behaviour studied, along with that of the newly synthesised lipids.

  12. Effect of ferrate on green algae removal.

    Science.gov (United States)

    Kubiňáková, Emília; Híveš, Ján; Gál, Miroslav; Fašková, Andrea

    2017-09-01

    Green algae Cladophora aegagropila, present in cooling water of thermal power plants, causes many problems and complications, especially during summer. However, algae and its metabolites are rarely eliminated by common removal methods. In this work, the elimination efficiency of electrochemically prepared potassium ferrate(VI) on algae from cooling water was investigated. The influence of experimental parameters, such as Fe(VI) dosage, application time, pH of the system, temperature and hydrodynamics of the solution on removal efficiency, was optimized. This study demonstrates that algae C. aegagropila can be effectively removed from cooling water by ferrate. Application of ferrate(VI) at the optimized dosage and under the suitable conditions (temperature, pH) leads to 100% removal of green algae Cladophora from the system. Environmentally friendly reduction products (Fe(III)) and coagulation properties favour the application of ferrate for the treatment of water contaminated with studied microorganisms compared to other methods such as chlorination and use of permanganate, where harmful products are produced.

  13. Radiation effects on algae and its application

    International Nuclear Information System (INIS)

    Dwivedi, Rakesh Kumar

    2013-01-01

    The effects of radiation on algae have been summarized in this article. Today, algae are being considered to have the great potential to fulfill the demand of food, fodder, fuel and various pharmaceutical products. Red algae are particularly rich in the content of polysaccharides present in their cell wall. For isolation of these polysaccharides, separation of cells cemented together by middle lamella is essential. The gamma rays are known to bring about biochemical changes in the cell wall and cause the breakdown of the middle lamella. These rays ate also known to speed up the starch sugar inter-conversion in the cells which is very useful for the tapping the potential of algae to be used as biofuel as well as in pharmaceutical industries. Cyanobacteria, among algae and other plants are more resistant to the radiation. In some cyanobacteria the radiation treatment is known to enhance the resistance against the antibiotics. Radiation treatment is also known to enhance the diameter of cell and size of the nitrogen fixing heterocyst. (author)

  14. Controlled regular locomotion of algae cell microrobots.

    Science.gov (United States)

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

    2016-06-01

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

  15. Upstream factors affecting Tualatin River algae—Tracking the 2008 Anabaena algae bloom to Wapato Lake, Oregon

    Science.gov (United States)

    Rounds, Stewart A.; Carpenter, Kurt D.; Fesler, Kristel J.; Dorsey, Jessica L.

    2015-12-17

    Significant Findings A large bloom that included floating mats of the blue-green algae Anabaena flos-aquae occurred in the lower 20 miles of the Tualatin River in northwestern Oregon between July 7 and July 17, 2008.

  16. Freshwater algae of the Nevada Test Site

    International Nuclear Information System (INIS)

    Taylor, W.D.; Giles, K.R.

    1979-06-01

    Fifty-two species of freshwater algae were identified in samples collected from the eight known natural springs of the Nevada Test Site. Although several species were widespread, 29 species were site specific. Diatoms provided the greatest variety of species at each spring. Three-fifths of all algal species encountered were diatoms. Well-developed mats of filamentous green algae (Chlorophyta) were common in many of the water tanks associated with the springs and accounted for most of the algal biomass. Major nutrients were adequate, if not abundant, in most spring waters - growth being limited primarily by light and physical habitat. There was some evidence of cesium-137 bioconcentration by algae at several of the springs

  17. Freshwater algae of the Nevada Test Site

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, W.D.; Giles, K.R.

    1979-06-01

    Fifty-two species of freshwater algae were identified in samples collected from the eight known natural springs of the Nevada Test Site. Although several species were widespread, 29 species were site specific. Diatoms provided the greatest variety of species at each spring. Three-fifths of all algal species encountered were diatoms. Well-developed mats of filamentous green algae (Chlorophyta) were common in many of the water tanks associated with the springs and accounted for most of the algal biomass. Major nutrients were adequate, if not abundant, in most spring waters - growth being limited primarily by light and physical habitat. There was some evidence of cesium-137 bioconcentration by algae at several of the springs.

  18. Behaviour of technetium in marine algae

    International Nuclear Information System (INIS)

    Bonotto, S.; Kirchmann, R.; Van Baelen, J.; Hurtger, C.; Cogneau, M.; Van der Ben, D.; Verthe, C.; Bouquegneau, J.M.

    1985-01-01

    Uptake and distribution of technetium were studied in several green (Acetabularia acetabulum, Boergesenia forbesii, Ulva lactuca) and brown (Ascophyllum nodosum, Fucus serratus, Fucus spiralis and Fucus vesiculosus) marine algae. Technetium was supplied to the algae as Tc-95m-pertechnetate. Under laboratory conditions, the algae were capable of accumulating technetium, with the exception, however, of Boergesenia, which showed concentration factors (C.F.) comprised between 0.28 and 0.71. The concentration of technetium-99 in Fucus spiralis, collected along the Belgian coast, was measured by a radiochemical procedure. The intracellular distribution of technetium was studied by differential centrifugation in Acetabularia and by the puncturing technique in Boergesenia. The chemical forms of technetium penetrated into the cells were investigated by selective chemical extractions, molecular sieving and thin layer chromatography

  19. Behaviour of technetium in marine algae

    International Nuclear Information System (INIS)

    Bonotto, S.; Kirchmann, R.; Baelen, J. van; Hurtgen, C.; Cogneau, M.; Ben, D. van der; Verthe, C.; Bouquegneau, J.M.

    1986-01-01

    Uptake and distribution of technetium were studied in several green (Acetabularia acetabulum, Boergesenia forbesii, Ulva lactuca) and brown (Ascophyllum nodosum, Fucus serratus, Fucus spiralis and Fucus vesiculosus) marine algae. Technetium was supplied to the algae as Tc-95-pertechnetate. Under laboratory conditions, the algae were capable of accumulating technetium, with the exception, however, of Boergesenia, which showed concentration factors (C.F.) comprised between 0.28 and 0.71. The concentration of technetium-99 in Fucus spiralis, collected along the Belgian coast, was measured by a radiochemical procedure. The intracellular distribution of technetium was studied by differential centrifugation in Acetabularia and by the puncturing technique in Boergesenia. The chemical forms of technetium penetrated into the cells were investigated by selective chemical extractions, molecular sieving and thin layer chromatography. (author)

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

    International Nuclear Information System (INIS)

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

    2000-01-01

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

  1. Serpins in plants and green algae

    DEFF Research Database (Denmark)

    Roberts, Thomas Hugh; Hejgaard, Jørn

    2008-01-01

    . Serpins have been found in diverse species of the plant kingdom and represent a distinct clade among serpins in multicellular organisms. Serpins are also found in green algae, but the evolutionary relationship between these serpins and those of plants remains unknown. Plant serpins are potent inhibitors...... of mammalian serine proteinases of the chymotrypsin family in vitro but, intriguingly, plants and green algae lack endogenous members of this proteinase family, the most common targets for animal serpins. An Arabidopsis serpin with a conserved reactive centre is now known to be capable of inhibiting...

  2. [Comparative chemical composition of the Barents Sea brown algae].

    Science.gov (United States)

    Obluchinskaia, E D

    2008-01-01

    Comparative study of phytochemical compositions of the most widespread brown algae species (one laminarian and four fucoid algae) from Barents Sea has been performed. A modified technique for mannitol determination in brown algae is proposed. It was revealed that fucus algae (fam. Fucaceae) contain 3% (of total dry weight) less mannitol than laminaria (Laminaria saccharina). The contents of alginic acid and laminaran in the Barents Sea fucoids are more than 10% less compared to laminaria. The alga L. saccharina contains almost two times more iodine than the species of fam. Fucaceae. The amounts of fucoidan and sum lipids in the Barents Sea fucoid algae is higher than in Laminaria saccharina (4-7% and 1-3%, respectively). In terms of contents of main biologically active compounds, fucus and laminarian algae from Barents Sea are inferior to none of the Far-Eastern species. The Barents Sea algae may become an important source of biologically active compounds.

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

    Science.gov (United States)

    Porter, Lee A.

    1985-01-01

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

  4. Association of thraustochytrids and fungi with living marine algae

    Digital Repository Service at National Institute of Oceanography (India)

    Raghukumar, C.; Nagarkar, S.; Raghukumar, S.

    only in C. clavulatum, Sargassum cinereum and Padina tetrastromatica whilst mycelial fungi occurred in all. Growth experiments in the laboratory indicated that the growth of thraustochytrids was inhibited on live algae, whereas killed algae supported...

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

    Science.gov (United States)

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

  6. Excitation-induced dynamics of external pH pattern in Chara corallina cells and its dependence on external calcium concentration.

    Science.gov (United States)

    Eremin, Alexey; Bulychev, Alexander; Krupenina, Natalia A; Mair, Thomas; Hauser, Marcus J B; Stannarius, Ralf; Müller, Stefan C; Rubin, Andrei B

    2007-01-01

    The influence of cell excitation and external calcium level on the dynamics of light-induced pH bands along the length of Chara corallina cells is studied in the present paper. Generation of an action potential (AP) transiently quenched these pH patterns, which was more pronounced at 0.05-0.1 mM Ca2+ than at higher concentrations of Ca2+ (0.6-2 mM) in the medium. After transient smoothing of the pH bands, some alkaline peaks reemerged at slightly shifted positions in media with low Ca2+ concentrations, while at high Ca2+ concentrations, the alkaline spots reappeared exactly at their initial positions. This Ca2+ dependency has been revealed by both digital imaging and pH microelectrodes. The stabilizing effect of external Ca2+ on the locations of recovering alkaline peaks is supposedly due to formation of a physically heterogeneous environment around the cell owing to precipitation of CaCO3 in the alkaline zones at high Ca2+ during illumination. The elevation of local pH by dissolving CaCO3 facilitates the reappearance of alkaline spots at their initial locations after temporal suppression caused by cell excitation. At low Ca2+ concentrations, when the solubility product of CaCO3 is not attained, the alkaline peaks are not stabilized by CaCO3 dissolution and may appear at random locations.

  7. Comparative study of the oospore morphology of two populations of a rare species Chara baueri A. Braun in Cedynia (Poland and Batzlow (Germany

    Directory of Open Access Journals (Sweden)

    Andrzej Pukacz

    2012-06-01

    Full Text Available Morphological features of oospores of Chara baueri A. Braun, one of the rarest charophyte species worldwide, were studied based on 100 oospores collected from a small and temporarily dried mid-field pond near Cedynia, Western Poland. This is the first Polish and fifth presently known locality of this species. For comparison 67 oospores from a German population (similar pond localized near Batzlow, Germany were also measured. So far, data on morphology of C. baueri oospores as well as the species ecology are limited. The only more detailed study of oospores for this species was earlier performed on 15 oospores from Kazakhstan. Largest polar axis (LPA, length, largest equatorial diameter (LED, width, isopolarity index (ISI = LPA/LED × 100, number of ridges, width of fossa, distance from apical pole to LED (AND and anisipolarity index (ANI = AND/LPA × 100 were measured. The comparative analysis revealed that the oospores from Poland are generally bigger and more prolate than the Ger­man ones. The differences for most of studied parameters were statistically significant. The finding is discussed in the context of habitat differentiation of both studied sites. Moreover, the results obtained of oospore measurements for both populations differs from most of the data known so far from the literature.

  8. Promoter trans-activation of protooncogenes c-fos and c-myc, but not c-Ha-ras, by products of adenovirus early region 1A

    International Nuclear Information System (INIS)

    Sassone-Corsi, P.; Borrelli, E.

    1987-01-01

    The E1A (early region 1A) oncogene products of adenovirus type 2 trans-activate the other early viral transcription units, as well as some cellular promoters. Using a short-term cotransfection assay in murine NIH 3T3 fibroblasts, we show that c-fos and c-myc promoter activities are stimulated by the E1A proteins, whereas c-Ha-ras transcription is not affected. The product of E1A 13S mRNA is responsible for the trans-activation, whereas the 12S mRNA product has no effect. Analysis of the c-fos promoter sequences required for the E1A stimulation shows that responsive sequences are located between positions -402 and -240 upstream of the transcription initiation site. This same region also contains the c-fos serum-responsive element. Furthermore, transcription of the endogenous c-fos gene in HeLa cells is increased after E1A transfection

  9. Tumor promoting effect of phenolphthalein on development of lung tumors induced by N-ethyl-N-nitrosourea in transgenic mice carrying human prototype c-Ha-ras gene.

    Science.gov (United States)

    Imaoka, Masako; Kashida, Yoko; Watanabe, Takao; Ueda, Makoto; Onodera, Hiroshi; Hirose, Masao; Mitsumori, Kunitoshi

    2002-06-01

    In order to examine tumor modifying effects of phenolphthalein (PhP), female transgenic mice carrying human prototype c-Ha-ras gene (rasH2 mice) were given a single intraperitoneal injection of 60 mg/kg body weight of N-ethyl-N-nitrosourea (ENU), followed by the diet containing 12,000 ppm PhP for 26-week. Histopathologically, alveolar hyperplasias, adenomas and adenocarcinomas were observed in the ENU + PhP group, but only hyperplasias and adenomas were observed in the ENU alone group. The incidence and multiplicity of adenocarcinomas in the ENU + PhP group was significantly increased as compared to that in the ENU alone group. The combined multiplicity of adenomas and adenocarcinomas in this group was also significantly higher than that of the ENU alone group. In addition, the ratio of area of adenomas in the ENU + PhP group was significantly higher than that in the ENU alone group. The result of our study suggests that PhP has a clear tumor promoting effect in the lung of rasH2 mice.

  10. Effect of kinetin on the course of cell cycle in successive developmental stages of the antheridial filaments of Chara vulgaris L.

    Directory of Open Access Journals (Sweden)

    Mirosław Godlewski

    2014-01-01

    Full Text Available Effects of kinetin on the course of cell cycle in successive developmental stages of the antheridial filaments of Chara vulgaris L. were investigated. A shortening of the duration of cell cycles has been observed, particularly in initial. and final developmental stages. S phase. shortened in all stages whereas G2 phase+mitosis shortened in early but become longer in late developmental stages of filaments. Incorporation of 14C-adenine into cell nuclei increased after kinetin treatment in 4- and 8-celled filaments whereas that of 3H-phenylalanine increased in 8- and particularly 16-celled ones. This plant growth regulator stimulated also the 3H-thymidine incorporation into cells in studied developmental stages of filaments. The stimulation of radioactive phenylalanine incorporation into nucleus and cytoplasm was stronger in late G2 phase. A participation of cytokinins in the control of cell cycle in relation to process of differentiation of antheridial cells is discussed. A possibility of changes in the cytokinin content in antheridia and antheridial filament cells during their; development has been postulated.

  11. Harmful impact of filamentous algae (Spirogyra sp.) on juvenile crayfish

    OpenAIRE

    Ulikowski Dariusz; Chybowski Łucjan; Traczuk Piotr

    2015-01-01

    The aim of this study was to determine the impact of filamentous algae on the growth and survival of juvenile narrow-clawed crayfish, Astacus leptodactylus (Esch.), in rearing basins. Three stocking variants were used: A - basins with a layer of filamentous algae without imitation mineral substrate; B - basins with a layer of filamentous algae with imitation mineral substrate; C - basins without filamentous algae but with mineral substrate. The crayfish were reared from June 12 to October 10 ...

  12. Green algae in alpine biological soil crust communities: acclimation strategies against ultraviolet radiation and dehydration.

    Science.gov (United States)

    Karsten, Ulf; Holzinger, Andreas

    2014-01-01

    Green algae are major components of biological soil crusts in alpine habitats. Together with cyanobacteria, fungi and lichens, green algae form a pioneer community important for the organisms that will succeed them. In their high altitudinal habitat these algae are exposed to harsh and strongly fluctuating environmental conditions, mainly intense irradiation, including ultraviolet radiation, and lack of water leading to desiccation. Therefore, green algae surviving in these environments must have evolved with either avoidance or protective strategies, as well as repair mechanisms for damage. In this review we have highlighted these mechanisms, which include photoprotection, photochemical quenching, and high osmotic values to avoid water loss, and in some groups flexibility of secondary cell walls to maintain turgor pressure even in water-limited situations. These highly specialized green algae will serve as good model organisms to study desiccation tolerance or photoprotective mechanisms, due to their natural capacity to withstand unfavorable conditions. We point out the urgent need for modern phylogenetic approaches in characterizing these organisms, and molecular methods for analyzing the metabolic changes involved in their adaptive strategies.

  13. KAROTENOID PADA ALGAE: KAJIAN TENTANG BIOSINTESIS, DISTRIBUSI SERTA FUNGSI KAROTENOID

    OpenAIRE

    Merdekawati, Windu; Karwur, Ferry F.; Susanto, A. B.

    2017-01-01

    ABSTRAK   Karotenoid terdistribusi pada archaea, bakteri, jamur, tumbuhan, hewan serta algae. Karotenoid dihasilkan dari komponen isopentenyl pyrophosphate (IPP) yang mengalami proses secara bertahap untuk membentuk beragam jenis karotenoid. Terdapat dua kelompok karotenoid yaitu karoten dan xantofil dengan berbagai jenis turunannya. Struktur kimia pada karotenoid algae yaitu allene, acetylene serta acetylated carotenoids. Algae mempunyai karotenoid spesifik yang menarik untuk dipe...

  14. Relationships between algae taxa and physico-chemical ...

    African Journals Online (AJOL)

    A study of algae flora was performed on 16 samples collected in different aquatic environments in Bamenda (Cameroon) in order to evidence the relationships between algae assemblages and physico-chemical parameters of the milieu. A total of 22 algae species were identified, the most represented class being ...

  15. Composition of phytoplankton algae in Gubi Reservoir, Bauchi ...

    African Journals Online (AJOL)

    Studies on the distribution, abundance and taxonomic composition of phytoplankton algae in Gubi reservoir were carried out for 12 months (from January to December 1995). Of the 26 algal taxa identified, 14 taxa belonged to the diatoms, 8 taxa were green algae while 4 taxa belonged to the blue-green algae. Higher cell ...

  16. Can the primary algae production be measured precisely?

    International Nuclear Information System (INIS)

    Olesen, M.; Lundsgaard, C.

    1996-01-01

    Algae production in seawater is extremely important as a basic link in marine food chains. Evaluation of the algae quantity is based on 14CO 2 tracer techniques while natural circulation and light absorption in seawater is taken insufficiently into account. Algae production can vary by 500% in similar nourishment conditions, but varying water mixing conditions. (EG)

  17. Inventory of North-West European algae initiatives

    NARCIS (Netherlands)

    Spruijt, J.

    2015-01-01

    In 2012 an inventory of North-West European (NWE) algae initiatives was carried out to get an impression of the market and research activities on algae production and refinery, especially for bioenergy purposes. A questionnaire was developed that would provide the EnAlgae project with information on

  18. New methodologies for integrating algae with CO2 capture

    NARCIS (Netherlands)

    Hernandez Mireles, I.; Stel, R.W. van der; Goetheer, E.L.V.

    2014-01-01

    It is generally recognized, that algae could be an interesting option for reducing CO2 emissions. Based on light and CO2, algae can be used for the production various economically interesting products. Current algae cultivation techniques, however, still present a number of limitations. Efficient

  19. Agricultural importance of algae | Abdel-Raouf | African Journal of ...

    African Journals Online (AJOL)

    Algae are a large and diverse group of microorganisms that can carry out photosynthesis since they capture energy from sunlight. Algae play an important role in agriculture where they are used as biofertilizer and soil stabilizers. Algae, particularly the seaweeds, are used as fertilizers, resulting in less nitrogen and ...

  20. The algae of Gaborone wastewater stabilization ponds: Implications ...

    African Journals Online (AJOL)

    The types of algae found in the wastewater stabilization ponds in Gaborone were studied. Being the base of the food chain in any aquatic habitat, algae contribute significantly to the functioning and value of the ponds. The (liversit)' and abundance of the algae in the two pond systems at Broadhurst and Phakalane were ...

  1. Extraction and physico-chemical characterization of a versatile biodegradable polysaccharide obtained from green algae.

    Science.gov (United States)

    Alves, Anabela; Caridade, Sofia G; Mano, João F; Sousa, Rui A; Reis, Rui L

    2010-10-13

    During the last years, considerable attention has been given to different marine organisms, like algae, as potential sources of valuable materials. The continuous demand for novel materials and technologies is high and research on the underexploited marine green algae, including its polysaccharidic part-ulvan, has increased accordingly. In this research work, a novel method for extraction of ulvan from green algae is proposed and demonstrated successfully. Different characterization techniques were employed to characterize the isolated algal polysaccharide, namely, on what concerns its thermal trace and crystallinity. Upon heating, ulvan behaves as a non-meltable polysaccharide that is thermally stable before degradation at 220°C. Ulvan is semi-crystalline in nature and possesses high hygroscopic features, as revealed in this research work. Due to its properties, ulvan can be considered, pure or modified, as a versatile biodegradable polymer for different applications, including tissue engineering and regenerative medicine. Copyright © 2010 Elsevier Ltd. All rights reserved.

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

    Science.gov (United States)

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

    2015-03-01

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

  3. Photoprotection strategies of the alga Nannochloropsis gaditana

    NARCIS (Netherlands)

    Chukhutsina, Volha U.; Fristedt, Rikard; Morosinotto, Tomas; Croce, Roberta

    2017-01-01

    Nannochloropsis spp. are algae with high potential for biotechnological applications due to their capacity to accumulate lipids. However, little is known about their photosynthetic apparatus and acclimation/photoprotective strategies. In this work, we studied the mechanisms of non-photochemical

  4. Selenium accumulation and metabolism in algae.

    Science.gov (United States)

    Schiavon, Michela; Ertani, Andrea; Parrasia, Sofia; Vecchia, Francesca Dalla

    2017-08-01

    Selenium (Se) is an intriguing element because it is metabolically required by a variety of organisms, but it may induce toxicity at high doses. Algae primarily absorb selenium in the form of selenate or selenite using mechanisms similar to those reported in plants. However, while Se is needed by several species of microalgae, the essentiality of this element for plants has not been established yet. The study of Se uptake and accumulation strategies in micro- and macro-algae is of pivotal importance, as they represent potential vectors for Se movement in aquatic environments and Se at high levels may affect their growth causing a reduction in primary production. Some microalgae exhibit the capacity of efficiently converting Se to less harmful volatile compounds as a strategy to cope with Se toxicity. Therefore, they play a crucial role in Se-cycling through the ecosystem. On the other side, micro- or macro-algae enriched in Se may be used in Se biofortification programs aimed to improve Se content in human diet via supplementation of valuable food. Indeed, some organic forms of selenium (selenomethionine and methylselenocysteine) are known to act as anticarcinogenic compounds and exert a broad spectrum of beneficial effects in humans and other mammals. Here, we want to give an overview of the developments in the current understanding of Se uptake, accumulation and metabolism in algae, discussing potential ecotoxicological implications and nutritional aspects. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Isolation of glycoproteins from brown algae.

    OpenAIRE

    Surendraraj, Alagarsamy; Farvin Koduvayur Habeebullah , Sabeena; Jacobsen, Charlotte

    2015-01-01

    The present invention relates to a novel process for the isolation of unique anti-oxidative glycoproteins from the pH precipitated fractions of enzymatic extracts of brown algae. Two brown seaweeds viz, Fucus serratus and Fucus vesiculosus were hydrolysed by using 3 enzymes viz, Alcalase, Viscozyme and Termamyl and the glycoproteins were isolated from these enzyme extracts.

  6. Fucoidans — sulfated polysaccharides of brown algae

    Science.gov (United States)

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

    2009-08-01

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

  7. The ice nucleation activity of extremophilic algae

    Czech Academy of Sciences Publication Activity Database

    Kvíderová, Jana; Hájek, J.; Worland, M. R.

    2013-01-01

    Roč. 34, č. 2 (2013), s. 137-148 ISSN 0143-2044 R&D Projects: GA AV ČR KJB601630808; GA AV ČR KJB600050708 Institutional support: RVO:67985939 Keywords : Ice nucleation * snow algae * lichen photobionts Subject RIV: EF - Botanics Impact factor: 0.640, year: 2013

  8. Isolation of glycoproteins from brown algae

    DEFF Research Database (Denmark)

    2015-01-01

    The present invention relates to a novel process for the isolation of unique anti-oxidative glycoproteins from the pH precipitated fractions of enzymatic extracts of brown algae. Two brown seaweeds viz, Fucus serratus and Fucus vesiculosus were hydrolysed by using 3 enzymes viz, Alcalase, Viscozyme...

  9. Taxonomic Challenges and Distribution of Gracilarioid Algae ...

    African Journals Online (AJOL)

    This paper reviews the taxonomical literature of the gracilarioid algae from Tanzania, and provides information about their ecology and distribution based on an intensive regime of local collection. Its aim was to provide names, even if on a preliminary basis, for local gracilarioid taxa. Our revision shows that species ...

  10. Research for Developing Renewable Biofuels from Algae

    Energy Technology Data Exchange (ETDEWEB)

    Black, Paul N. [Univ. of Nebraska, Lincoln, NE (United States)

    2012-12-15

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

  11. Usos industriales de las algas diatomeas.

    OpenAIRE

    Illana Esteban, Carlos

    2007-01-01

    Las diatomeas son algas microscópicas que habitan tanto en aguas dulces como marinas. Aparte de su destacado papel en la cadena trófica de los ecosistemas acuáticos, con el tiempo forman depósitos a los que el hombre ha encontrado abundantes aplicaciones prácticas.

  12. The Biology of blue-green algae

    National Research Council Canada - National Science Library

    Carr, Nicholas G; Whitton, B. A

    1973-01-01

    .... This book, extensively illustrated and thoroughly referenced, will provide the source material for students, and experienced as well as new research workers should find it of great value. A series of short appendices summarize details of culture collections, media and some specialized aspects of growing blue-green algae.

  13. Spirulina: The Alga That Can End Malnutrition.

    Science.gov (United States)

    Fox, Ripley D.

    1985-01-01

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

  14. Sustainable Use Of Macro-Algae For Biogas Production In Latvian Conditions: A Preliminary Study Through An Integrated Mca And Lca Approach

    Directory of Open Access Journals (Sweden)

    Pastare Laura

    2014-12-01

    Full Text Available The study focuses on sustainability evaluation of an algae-based energy system in Latvia with a holistic and integrated approach of multi-criteria analysis combined with life cycle assessment (including a practical side - biogas yield experiments of locally available algae.

  15. Gain and loss of polyadenylation signals during evolution of green algae

    Directory of Open Access Journals (Sweden)

    Glöckner Gernot

    2007-04-01

    Full Text Available Abstract Background The Viridiplantae (green algae and land plants consist of two monophyletic lineages: the Chlorophyta and the Streptophyta. Most green algae belong to the Chlorophyta, while the Streptophyta include all land plants and a small group of freshwater algae known as Charophyceae. Eukaryotes attach a poly-A tail to the 3' ends of most nuclear-encoded mRNAs. In embryophytes, animals and fungi, the signal for polyadenylation contains an A-rich sequence (often AAUAAA or related sequence 13 to 30 nucleotides upstream from the cleavage site, which is commonly referred to as the near upstream element (NUE. However, it has been reported that the pentanucleotide UGUAA is used as polyadenylation signal for some genes in volvocalean algae. Results We set out to investigate polyadenylation signal differences between streptophytes and chlorophytes that may have emerged shortly after the evolutionary split between Streptophyta and Chlorophyta. We therefore analyzed expressed genes (ESTs from three streptophyte algae, Mesostigma viride, Klebsormidium subtile and Coleochaete scutata, and from two early-branching chlorophytes, Pyramimonas parkeae and Scherffelia dubia. In addition, to extend the database, our analyses included ESTs from six other chlorophytes (Acetabularia acetabulum, Chlamydomonas reinhardtii, Helicosporidium sp. ex Simulium jonesii, Prototheca wickerhamii, Scenedesmus obliquus and Ulva linza and one streptophyte (Closterium peracerosum. Our results indicate that polyadenylation signals in green algae vary widely. The UGUAA motif is confined to late-branching Chlorophyta. Most streptophyte algae do not have an A-rich sequence motif like that in embryophytes, animals and fungi. We observed polyadenylation signals similar to those of Arabidopsis and other land plants only in Mesostigma. Conclusion Polyadenylation signals in green algae show considerable variation. A new NUE (UGUAA was invented in derived chlorophytes and replaced

  16. Gain and loss of polyadenylation signals during evolution of green algae.

    Science.gov (United States)

    Wodniok, Sabina; Simon, Andreas; Glöckner, Gernot; Becker, Burkhard

    2007-04-18

    The Viridiplantae (green algae and land plants) consist of two monophyletic lineages: the Chlorophyta and the Streptophyta. Most green algae belong to the Chlorophyta, while the Streptophyta include all land plants and a small group of freshwater algae known as Charophyceae. Eukaryotes attach a poly-A tail to the 3' ends of most nuclear-encoded mRNAs. In embryophytes, animals and fungi, the signal for polyadenylation contains an A-rich sequence (often AAUAAA or related sequence) 13 to 30 nucleotides upstream from the cleavage site, which is commonly referred to as the near upstream element (NUE). However, it has been reported that the pentanucleotide UGUAA is used as polyadenylation signal for some genes in volvocalean algae. We set out to investigate polyadenylation signal differences between streptophytes and chlorophytes that may have emerged shortly after the evolutionary split between Streptophyta and Chlorophyta. We therefore analyzed expressed genes (ESTs) from three streptophyte algae, Mesostigma viride, Klebsormidium subtile and Coleochaete scutata, and from two early-branching chlorophytes, Pyramimonas parkeae and Scherffelia dubia. In addition, to extend the database, our analyses included ESTs from six other chlorophytes (Acetabularia acetabulum, Chlamydomonas reinhardtii, Helicosporidium sp. ex Simulium jonesii, Prototheca wickerhamii, Scenedesmus obliquus and Ulva linza) and one streptophyte (Closterium peracerosum). Our results indicate that polyadenylation signals in green algae vary widely. The UGUAA motif is confined to late-branching Chlorophyta. Most streptophyte algae do not have an A-rich sequence motif like that in embryophytes, animals and fungi. We observed polyadenylation signals similar to those of Arabidopsis and other land plants only in Mesostigma. Polyadenylation signals in green algae show considerable variation. A new NUE (UGUAA) was invented in derived chlorophytes and replaced not only the A-rich NUE but the complete poly

  17. Rapid Aggregation of Biofuel-Producing Algae by the Bacterium Bacillus sp. Strain RP1137

    Science.gov (United States)

    Powell, Ryan J.

    2013-01-01

    Algal biofuels represent one of the most promising means of sustainably replacing liquid fuels. However, significant challenges remain before alga-based fuels become competitive with fossil fuels. One of the largest challenges is the ability to harvest the algae in an economical and low-energy manner. In this article, we describe the isolation of a bacterial strain, Bacillus sp. strain RP1137, which can rapidly aggregate several algae that are candidates for biofuel production, including a Nannochloropsis sp. This bacterium aggregates algae in a pH-dependent and reversible manner and retains its aggregation ability after paraformaldehyde fixation, opening the possibility for reuse of the cells. The optimal ratio of bacteria to algae is described, as is the robustness of aggregation at different salinities and temperatures. Aggregation is dependent on the presence of calcium or magnesium ions. The efficiency of aggregation of Nannochloropsis oceanica IMET1 is between 70 and 95% and is comparable to that obtained by other means of harvest; however, the rate of harvest is fast, with aggregates forming in 30 s. PMID:23892750

  18. Towards a Sustainable Urban Metabolism: Algae-to-Energy Systems as Clean Cycles in the Urban Water Chain

    OpenAIRE

    Menger-Krug, Eve

    2013-01-01

    This study includes an analysis of the urban water chain in Germany (water supply, wastewater and sludge management); followed by an analysis of the integration of algae systems on the level of wastewater treatment plants. Then, the scope of the study is extended to put the results in context of the urban metabolism. The relevance of the urban water chain - with and without algae - for the urban energy balance and the urban flows of nutrients and anthropogenic micropollutants is assessed.

  19. Sulfated polysaccharides as bioactive agents from marine algae.

    Science.gov (United States)

    Ngo, Dai-Hung; Kim, Se-Kwon

    2013-11-01

    Recently, much attention has been paid by consumers toward natural bioactive compounds as functional ingredients in nutraceuticals. Marine algae are considered as valuable sources of structurally diverse bioactive compounds. Marine algae are rich in sulfated polysaccharides (SPs) such as carrageenans in red algae, fucoidans in brown algae and ulvans in green algae. These SPs exhibit many health beneficial nutraceutical effects such as antioxidant, anti-allergic, anti-human immunodeficiency virus, anticancer and anticoagulant activities. Therefore, marine algae derived SPs have great potential to be further developed as medicinal food products or nutraceuticals in the food industry. This contribution presents an overview of nutraceutical effects and potential health benefits of SPs derived from marine algae. Copyright © 2013 Elsevier B.V. All rights reserved.

  20. Multispectral sorter for rapid, nondestructive optical bioprospecting for algae biofuels

    Science.gov (United States)

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

    2014-03-01

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

  1. Taxonomic biodiversity of geniculate coralline red algae (Corallinales, Rhodophyta) from the Macaronesian region: summary and analysis

    Science.gov (United States)

    Rosas-Alquicira, Edgar F.; Riosmena-Rodríguez, Rafael; Afonso-Carrillo, Julio; Neto, Ana I.

    2011-06-01

    A catalog and critical review of species and infraspecific taxa of non-fossil geniculate coralline red algae (Corallinales, Rhodophyta) previously reported from the Macaronesian region are presented along with an assessment of species diversity in the region. Published records of geniculate coralline algae are included along with comments relating to type material. Within the catalog, taxa are organized alphabetically by genus and within this by final epithet. From the 31 taxa recorded, 4 are based on type collections from Macaronesian localities. The types of most species and infraspecific taxa reported from the region have yet to be re-examined in a modern context, and most Macaronesian records require verification. The biodiversity of Macaronesian geniculate coralline algae may be lower than current information indicates.

  2. Biogeochemical cycling of metals in freshwater algae from Manaus and Carajas, Brazil

    International Nuclear Information System (INIS)

    Konhauser, K.O.; Fyfe, W.S.

    1993-01-01

    Freshwater algae were analyzed in different riverine environments in Manaus and Carajas, Brazil. Filamentous algae from both locations were characterized by enhanced levels of a wide array of heavy metals. A comparison of the two main rivers in the Manaus area indicated that the algal samples from the solute-rich waters of the Rio Solimoes consistently contained higher metal concentrations than in the solute-deficient waters of the Rio Negro. A similar relationship also existed between algal samples collected from forested regions relative to adjacent deforested regions in the Carajas area. In the Rio Negro, diatoms were shown to be the most prolific eucaryotic microorganisms found in the study area. These siliceous algae were found adhering to a variety of submerged solid substrates, including wood, rocks, and leaves. The abundance of these unicellular micro-organisms suggested that the dissolved silicon levels of the Rio Negro were influenced by biological activity

  3. Biogeochemical cycling of metals in freshwater algae from Manaus and Carajas, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Konhauser, K.O.; Fyfe, W.S. (Univ. of Western Ontario, London (Canada). Dept. of Geology)

    Freshwater algae were analyzed in different riverine environments in Manaus and Carajas, Brazil. Filamentous algae from both locations were characterized by enhanced levels of a wide array of heavy metals. A comparison of the two main rivers in the Manaus area indicated that the algal samples from the solute-rich waters of the Rio Solimoes consistently contained higher metal concentrations than in the solute-deficient waters of the Rio Negro. A similar relationship also existed between algal samples collected from forested regions relative to adjacent deforested regions in the Carajas area. In the Rio Negro, diatoms were shown to be the most prolific eucaryotic microorganisms found in the study area. These siliceous algae were found adhering to a variety of submerged solid substrates, including wood, rocks, and leaves. The abundance of these unicellular micro-organisms suggested that the dissolved silicon levels of the Rio Negro were influenced by biological activity.

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

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, Douglas C.; Neuenschwander, Gary G.; Hart, Todd R.; Rotness, Leslie J.; Zacher, Alan H.; Santosa, Daniel M.; Valkenburt, Corinne; Jones, Susanne B.; Tjokro Rahardjo, Sandra A.

    2009-11-03

    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 Genifuel, which provided in-kind cost share to the project, are also included. The work conducted during this project involved developing and demonstrating on the bench-scale process technology at PNNL for catalytic hydrothermal gasification of lignin-rich biorefinery residues and algae. A technoeconomic assessment evaluated the use of the technology for energy recovery in a lignocellulosic ethanol plant.

  5. Investigation of uranium biosorption from aqueous solutions by Dictyopteris polypodioides brown algae

    International Nuclear Information System (INIS)

    Bampaiti, A.; Ege University, Izmir; Yusan, S.; Aytas, S.; Pavlidou, E.; Noli, F.

    2016-01-01

    The biosorption of uranium from aqueous solutions by Dictyopteris polypodioides brown algae was investigated. The effect of pH, uranium concentration, mass of the adsorbent, temperature and contact time on the removal efficiency were studied and the results were simulated by Langmuir, Freundlich and Dubinin-Radushkevich isotherm models. Kinetics data could be satisfactorily reproduced by the pseudo-second order equation and thermodynamic parameters were determined in order to evaluate the uranium uptake behavior. SEM/EDS and FTIR were additionally used to characterize the algae and comprehend the sorption process which can be described as a combination of several mechanisms, including physical sorption, ion exchange and complexation. (author)

  6. Biofuels from algae for sustainable development

    International Nuclear Information System (INIS)

    Demirbas, M. Fatih

    2011-01-01

    Microalgae are photosynthetic microorganisms that can produce lipids, proteins and carbohydrates in large amounts over short periods of time. These products can be processed into both biofuels and useful chemicals. Two algae samples (Cladophora fracta and Chlorella protothecoid) were studied for biofuel production. Microalgae appear to be the only source of renewable biodiesel that is capable of meeting the global demand for transport fuels. Microalgae can be converted to biodiesel, bioethanol, bio-oil, biohydrogen and biomethane via thermochemical and biochemical methods. Industrial reactors for algal culture are open ponds, photobioreactors and closed systems. Algae can be grown almost anywhere, even on sewage or salt water, and does not require fertile land or food crops, and processing requires less energy than the algae provides. Microalgae have much faster growth-rates than terrestrial crops. the per unit area yield of oil from algae is estimated to be from 20,000 to 80,000 liters per acre, per year; this is 7-31 times greater than the next best crop, palm oil. Algal oil can be used to make biodiesel for cars, trucks, and airplanes. The lipid and fatty acid contents of microalgae vary in accordance with culture conditions. The effect of temperature on the yield of hydrogen from two algae (C. fracta and C. protothecoid) by pyrolysis and steam gasification were investigated in this study. In each run, the main components of the gas phase were CO 2 , CO, H 2 , and CH 4 .The yields of hydrogen by pyrolysis and steam gasification processes of the samples increased with temperature. The yields of gaseous products from the samples of C. fracta and C. protothecoides increased from 8.2% to 39.2% and 9.5% to 40.6% by volume, respectively, while the final pyrolysis temperature was increased from 575 to 925 K. The percent of hydrogen in gaseous products from the samples of C. fracta and C. protothecoides increased from 25.8% to 44.4% and 27.6% to 48.7% by volume

  7. Marine algae as attractive source to skin care.

    Science.gov (United States)

    Berthon, Jean-Yves; Nachat-Kappes, Rachida; Bey, Mathieu; Cadoret, Jean-Paul; Renimel, Isabelle; Filaire, Edith

    2017-06-01

    As the largest organ in the human body, the skin has multiple functions of which one of the most important is the protection against various harmful stressors. The keratinised stratified epidermis and an underlying thick layer of collagen-rich dermal connective tissues are important components of the skin. The environmental stressors such as ultraviolet radiation (UVR) and pollution increase the levels of reactive oxygen species (ROS), contributing to clinical manifestations such as wrinkle formation and skin aging. Skin aging is related to the reduction of collagen production and decrease of several enzymatic activities including matrix metalloproteinases (MMPs), which degrade collagen structure in the dermis; and tissue inhibitor of metalloproteinases (TIMPs), which inhibit the action of MMPs. In addition to alterations of DNA, signal transduction pathways, immunology, UVR, and pollution activate cell surface receptors of keratinocytes and fibroblasts in the skin. This action leads to a breakdown of collagen in the extracellular matrix and a shutdown of new collagen synthesis. Therefore, an efficient antioxidants strategy is of major importance in dermis and epidermis layers. Marine resources have been recognised for their biologically active substances. Among these, marine algae are rich-sources of metabolites, which can be used to fight against oxidative stress and hence skin aging. These metabolites include, among others, mycosporine-like amino acids (MAAs), polysaccharides, sulphated polysaccharides, glucosyl glycerols, pigments, and polyphenols. This paper reviews the role of oxidative processes in skin damage and the action of the compounds from algae on the physiological processes to maintain skin health.

  8. Pretreatment of algae-laden and manganese-containing waters by oxidation-assisted coagulation: Effects of oxidation on algal cell viability and manganese precipitation.

    Science.gov (United States)

    Lin, Jr-Lin; Hua, Lap-Cuong; Wu, Yuting; Huang, Chihpin

    2016-02-01

    Preoxidation is manipulated to improve performance of algae and soluble manganese (Mn) removal by coagulation-sedimentation for water treatment plants (WTPs) when large amount of soluble Mn presents in algae-laden waters. This study aimed to investigate the effects of preoxidation on the performance of coagulation-sedimentation for the simultaneous removal of algae and soluble Mn, including ionic and complexed Mn. NaOCl, ClO2, and KMnO4 were used to pretreat such algae-laden and Mn containing waters. The variation of algal cell viability, residual cell counts, and concentrations of Mn species prior to and after coagulation-sedimentation step were investigated. Results show that NaOCl dosing was effective in reducing the viability of algae, but precipitated little Mn. ClO2 dosing had a strongest ability to lower algae viability and oxidize ionic and complexed soluble Mn, where KMnO4 dosing oxidized ionic and complexed Mn instead of reducing the viability of cells. Preoxidation by NaOCl only improved the algae removal by sedimentation, whereas most of soluble Mn still remained. On the other hand, ClO2 preoxidation substantially improved the performance of coagulation-sedimentation for simultaneous removal of algae and soluble Mn. Furthermore, KMnO4 preoxidation did improve the removal of algae by sedimentation, but left significant residual Mn in the supernatant. Images from FlowCAM showed changes in aspect ratio (AR) and transparency of algae-Mn flocs during oxidation-assisted coagulation, and indicates that an effective oxidation can improve the removal of most compact algae-Mn flocs by sedimentation. It suggests that an effective preoxidation for reducing algal cell viability and the concentration of soluble Mn is a crucial step for upgrading the performance of coagulation-sedimentation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. New records of benthic marine algae and Cyanobacteria for Costa Rica, and a comparison with other Central American countries

    Science.gov (United States)

    Bernecker, Andrea; Wehrtmann, Ingo S.

    2009-09-01

    We present the results of an intensive sampling program carried out from 2000 to 2007 along both coasts of Costa Rica, Central America. The presence of 44 species of benthic marine algae is reported for the first time for Costa Rica. Most of the new records are Rhodophyta (27 spp.), followed by Chlorophyta (15 spp.), and Heterokontophyta, Phaeophycea (2 spp.). Overall, the currently known marine flora of Costa Rica is comprised of 446 benthic marine algae and 24 Cyanobacteria. This species number is an under estimation, and will increase when species of benthic marine algae from taxonomic groups where only limited information is available (e.g., microfilamentous benthic marine algae, Cyanobacteria) are included. The Caribbean coast harbors considerably more benthic marine algae (318 spp.) than the Pacific coast (190 spp.); such a trend has been observed in all neighboring countries. Compared to other Central American countries, Costa Rica has the highest number of reported benthic marine algae; however, Panama may have a similarly high diversity after unpublished results from a Rhodophyta survey (Wysor, unpublished) are included. Sixty-two species have been found along both the Pacific and Caribbean coasts of Costa Rica; we discuss this result in relation to the emergence of the Central American Isthmus.

  10. The complete mitochondrial DNA sequences of Nephroselmis olivacea and Pedinomonas minor. Two radically different evolutionary patterns within green algae.

    Science.gov (United States)

    Turmel, M; Lemieux, C; Burger, G; Lang, B F; Otis, C; Plante, I; Gray, M W

    1999-09-01

    Green plants appear to comprise two sister lineages, Chlorophyta (classes Chlorophyceae, Ulvophyceae, Trebouxiophyceae, and Prasinophyceae) and Streptophyta (Charophyceae and Embryophyta, or land plants). To gain insight into the nature of the ancestral green plant mitochondrial genome, we have sequenced the mitochondrial DNAs (mtDNAs) of Nephroselmis olivacea and Pedinomonas minor. These two green algae are presumptive members of the Prasinophyceae. This class is thought to include descendants of the earliest diverging green algae. We find that Nephroselmis and Pedinomonas mtDNAs differ markedly in size, gene content, and gene organization. Of the green algal mtDNAs sequenced so far, that of Nephroselmis (45,223 bp) is the most ancestral (minimally diverged) and occupies the phylogenetically most basal position within the Chlorophyta. Its repertoire of 69 genes closely resembles that in the mtDNA of Prototheca wickerhamii, a later diverging trebouxiophycean green alga. Three of the Nephroselmis genes (nad10, rpl14, and rnpB) have not been identified in previously sequenced mtDNAs of green algae and land plants. In contrast, the 25,137-bp Pedinomonas mtDNA contains only 22 genes and retains few recognizably ancestral features. In several respects, including gene content and rate of sequence divergence, Pedinomonas mtDNA resembles the reduced mtDNAs of chlamydomonad algae, with which it is robustly affiliated in phylogenetic analyses. Our results confirm the existence of two radically different patterns of mitochondrial genome evolution within the green algae.

  11. Radiokinetic study in betony marine algae

    International Nuclear Information System (INIS)

    Azevedo Gouvea, V. de.

    1981-01-01

    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 concentration and loss of radionuclides such as 137 Cs, 51 Cr, 60 Co and 131 I were performed in 1000cm 3 aquarium under controlled laboratory conditions, using a single channel gamma counting system, to study the species of algae most frequently found in the region. The concentration and loss parameters for all the species and radionuclides studied were obtained from the normalized results. The loss parameters were computerwise adjusted using Powell's multiparametric method. (author)

  12. Hyperaccumulation of radioactive isotopes by marine algae

    International Nuclear Information System (INIS)

    Ishii, Toshiaki; Hirano, Shigeki; Watabe, Teruhisa

    2003-01-01

    Hyperaccumlators are effective indicator organisms for monitoring marine pollution by heavy metals and artificial radionuclides. We found a green algae, Bryopsis maxima that hyperaccumulate a stable and radioactive isotopes such as Sr-90, Tc-99, Ba-138, Re-187, and Ra-226. B. maxima showed high concentration factors for heavy alkali earth metals like Ba and Ra, compared with other marine algae in Japan. Furthermore, this species had the highest concentrations for Tc-99 and Re-187. The accumulation and excretion patterns of Sr-85 and Tc-95m were examined by tracer experiments. The chemical states of Sr and Re in living B. maxima were analyzed by HPLC-ICP/MS, LC/MS, and X-ray absorption fine structure analysis using synchrotron radiation. (author)

  13. Multiplicity of viral infection in brown algae

    OpenAIRE

    Stevens, Kim

    2014-01-01

    Brown algae are important primary producers and habitat formers in coastal environments and are believed to have evolved multicellularity independently of the other eukaryotes. The phaeoviruses that infect them form a stable lysogenic relationship with their host via genome integration, but have only been extensively studied in two genera: Ectocarpus and Feldmannia. In this study I aim to improve our understanding of the genetic diversity, host range and distribution of phaeoviruses. Seq...

  14. Algae-Derived Dietary Ingredients Nourish Animals

    Science.gov (United States)

    2015-01-01

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

  15. Electro-coagulation-flotation process for algae removal

    International Nuclear Information System (INIS)

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

    2010-01-01

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

  16. Regulating cellular trace metal economy in algae.

    Science.gov (United States)

    Blaby-Haas, Crysten E; Merchant, Sabeeha S

    2017-10-01

    As indispensable protein cofactors, Fe, Mn, Cu and Zn are at the center of multifaceted acclimation mechanisms that have evolved to ensure extracellular supply meets intracellular demand. Starting with selective transport at the plasma membrane and ending in protein metalation, metal homeostasis in algae involves regulated trafficking of metal ions across membranes, intracellular compartmentalization by proteins and organelles, and metal-sparing/recycling mechanisms to optimize metal-use efficiency. Overlaid on these processes are additional circuits that respond to the metabolic state as well as to the prior metal status of the cell. In this review, we focus on recent progress made toward understanding the pathways by which the single-celled, green alga Chlamydomonas reinhardtii controls its cellular trace metal economy. We also compare these mechanisms to characterized and putative processes in other algal lineages. Photosynthetic microbes continue to provide insight into cellular regulation and handling of Cu, Fe, Zn and Mn as a function of the nutritional supply and cellular demand for metal cofactors. New experimental tools such as RNA-Seq and subcellular metal imaging are bringing us closer to a molecular understanding of acclimation to supply dynamics in algae and beyond. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Functional properties of carotenoids originating from algae.

    Science.gov (United States)

    Christaki, Efterpi; Bonos, Eleftherios; Giannenas, Ilias; Florou-Paneri, Panagiota

    2013-01-15

    Carotenoids are isoprenoid molecules which are synthesised de novo by photosynthetic plants, fungi and algae and are responsible for the orange, yellow and some red colours of various fruits and vegetables. Carotenoids are lipophilic compounds, some of which act as provitamins A. These compounds can be divided into xanthophylls and carotenes. Many macroalgae and microalgae are rich in carotenoids, where these compounds aid in the absorption of sunlight. Industrially, these carotenoids are used as food pigments (in dairy products, beverages, etc.), as feed additives, in cosmetics and in pharmaceuticals, especially nowadays when there is an increasing demand by consumers for natural products. Production of carotenoids from algae has many advantages compared to other sources; for example, their production is cheap, easy and environmentally friendly; their extraction is easier, with higher yields, and there is no lack of raw materials or limited seasonal variation. Recently, there has been considerable interest in dietary carotenoids with respect to their antioxidant properties and their ability to reduce the incidence of some chronic diseases where free radicals are involved. Possibly, carotenoids protect cells from oxidative stress by quenching singlet oxygen damage with various mechanisms. Therefore, carotenoids derived from algae could be a leading natural resource in the research for potential functional ingredients. Copyright © 2012 Society of Chemical Industry.

  18. Contrasting effects of ocean acidification on tropical fleshy and calcareous algae

    Directory of Open Access Journals (Sweden)

    Maggie Dorothy Johnson

    2014-05-01

    Full Text Available Despite the heightened awareness of ocean acidification (OA effects on marine organisms, few studies empirically juxtapose biological responses to CO2 manipulations across functionally distinct primary producers, particularly benthic algae. Algal responses to OA may vary because increasing CO2 has the potential to fertilize photosynthesis but impair biomineralization. Using a series of repeated experiments on Palmyra Atoll, simulated OA effects were tested across a suite of ecologically important coral reef algae, including five fleshy and six calcareous species. Growth, calcification and photophysiology were measured for each species independently and metrics were combined from each experiment using a meta-analysis to examine overall trends across functional groups categorized as fleshy, upright calcareous, and crustose coralline algae (CCA. The magnitude of the effect of OA on algal growth response varied by species, but the direction was consistent within functional groups. Exposure to OA conditions generally enhanced growth in fleshy macroalgae, reduced net calcification in upright calcareous algae, and caused net dissolution in CCA. Additionally, three of the five fleshy seaweeds tested became reproductive upon exposure to OA conditions. There was no consistent effect of OA on algal photophysiology. Our study provides experimental evidence to support the hypothesis that OA will reduce the ability of calcareous algae to biomineralize. Further, we show that CO2 enrichment either will stimulate population or somatic growth in some species of fleshy macroalgae. Thus, our results suggest that projected OA conditions may favor non-calcifying algae and influence the relative dominance of fleshy macroalgae on reefs, perpetuating or exacerbating existing shifts in reef community structure.

  19. Contrasting effects of ocean acidification on tropical fleshy and calcareous algae.

    Science.gov (United States)

    Johnson, Maggie Dorothy; Price, Nichole N; Smith, Jennifer E

    2014-01-01

    Despite the heightened awareness of ocean acidification (OA) effects on marine organisms, few studies empirically juxtapose biological responses to CO2 manipulations across functionally distinct primary producers, particularly benthic algae. Algal responses to OA may vary because increasing CO2 has the potential to fertilize photosynthesis but impair biomineralization. Using a series of repeated experiments on Palmyra Atoll, simulated OA effects were tested across a suite of ecologically important coral reef algae, including five fleshy and six calcareous species. Growth, calcification and photophysiology were measured for each species independently and metrics were combined from each experiment using a meta-analysis to examine overall trends across functional groups categorized as fleshy, upright calcareous, and crustose coralline algae (CCA). The magnitude of the effect of OA on algal growth response varied by species, but the direction was consistent within functional groups. Exposure to OA conditions generally enhanced growth in fleshy macroalgae, reduced net calcification in upright calcareous algae, and caused net dissolution in CCA. Additionally, three of the five fleshy seaweeds tested became reproductive upon exposure to OA conditions. There was no consistent effect of OA on algal photophysiology. Our study provides experimental evidence to support the hypothesis that OA will reduce the ability of calcareous algae to biomineralize. Further, we show that CO2 enrichment either will stimulate population or somatic growth in some species of fleshy macroalgae. Thus, our results suggest that projected OA conditions may favor non-calcifying algae and influence the relative dominance of fleshy macroalgae on reefs, perpetuating or exacerbating existing shifts in reef community structure.

  20. Factors influencing stable isotopes and growth of algae in oil sands aquatic reclamation.

    Science.gov (United States)

    Boutsivongsakd, Monique; Farwell, Andrea J; Chen, Hao; Dixon, D George

    2015-01-01

    Previous studies reported (15)N enrichment of biota in reclamation wetlands that contain oil sands processed material (e.g., processed water and tailings); however, there is little information on the factors controlling (15)N enrichment in these systems. In this microcosm study, the aim was to examine stable C and N isotopes and growth (chlorophyll a [chl a] and dry weight) of algae as a function of exposure to different sources and concentrations of water-soluble fractions (WSF) derived from tailings. Two sources of tailings including mature fine tailings (MFT) and consolidated tailings (CT) and peat-mineral overburden were utilized to generate separate WSF that differed in water quality. In general, there was (15)N enrichment of filamentous algae along the increasing gradient of WSF/nutrient concentrations in both CT and peat microcosms, and among the different sources, algae were more (15)N enriched in CT WSF than in peat WSF. Growth of filamentous algae was inhibited at higher WSF concentrations, possibly due to reduced light availability at elevated levels of fine clay particles in MFT microcosms and colored dissolved organic carbon (DOC) in peat microcosms. Filamentous algae displayed lower biomass and (15)N depletion in 100% peat WSF. This study indicated that both the quality (source) and quantity of WSF affected algal growth and directly and/or indirectly influenced δ(15)N of algae. The distinct (15)N enrichment of primary producers derived from tailings suggest that stable N isotopes might be useful to trace exposure to oil sands processed material in biota that utilize these resources in reclaimed systems constructed with tailings or natural systems that receive tailings dyke seepage.

  1. Ecotoxicological effects of carbon nanomaterials on algae, fungi and plants.

    Science.gov (United States)

    Basiuk, Elena V; Ochoa-Olmos, Omar E; De la Mora-Estrada, León F

    2011-04-01

    The ecotoxicological effects of carbon nanomateriales (CNMs), namely fullerenes and carbon nanotubes, on algae, fungi and plants are analyzed. In different toxicity tests, both direct and indirect effects were found. The direct effects are determined by nanomaterial chemical composition and surface reactivity, which might catalyze redox reactions in contact with organic molecules and affect respiratory processes. Some indirect effects of carbon nanoparticles (CNPs) are physical restraints or release of toxic ions. Accumulation of CNPs in photosynthetic organs provokes obstruction in stomata, foliar heating and alteration in physiological processes. The phytotoxicity studies of CNMs should be focused on determining phytotoxicity mechanisms, size distribution of CNPs in solution, uptake and translocation of nanoparticles by plants, on characterization of their physical and chemical properties in rhizosphere and on root surfaces. More studies on plants and algae, as a part of food chain, are needed to understand profoundly the toxicity and health risks of CNMs as ecotoxicological stressors. Correct and detailed physical and chemical characterization of CNMs is very important to establish the exposure conditions matching the realistic ones. Ecotoxicity experiments should include examinations of both short and long-term effects. One must take into account that real carbon nanomaterials are complex mixtures of carbon forms and metal residues of variable chemistry and particle size, and the toxicity reported may reflect these byproducts/residues/impurities rather than the primary material structure. One more recommendation is not only to focus on the inherent toxicity of nanoparticles, but also consider their possible interactions with existing environmental contaminants.

  2. Halophytes, Algae, and Bacteria Food and Fuel Feedstocks

    Science.gov (United States)

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

    2009-01-01

    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.

  3. Brown algae as a model for plant organogenesis.

    Science.gov (United States)

    Bogaert, Kenny A; Arun, Alok; Coelho, Susana M; De Clerck, Olivier

    2013-01-01

    Brown algae are an extremely interesting, but surprisingly poorly explored, group of organisms. They are one of only five eukaryotic lineages to have independently evolved complex multicellularity, which they express through a wide variety of morphologies ranging from uniseriate branched filaments to complex parenchymatous thalli with multiple cell types. Despite their very distinct evolutionary history, brown algae and land plants share a striking amount of developmental features. This has led to an interest in several aspects of brown algal development, including embryogenesis, polarity, cell cycle, asymmetric cell division and a putative role for plant hormone signalling. This review describes how investigations using brown algal models have helped to increase our understanding of the processes controlling early embryo development, in particular polarization, axis formation and asymmetric cell division. Additionally, the diversity of life cycles in the brown lineage and the emergence of Ectocarpus as a powerful model organism, are affording interesting insights on the molecular mechanisms underlying haploid-diploid life cycles. The use of these and other emerging brown algal models will undoubtedly add to our knowledge on the mechanisms that regulate development in multicellular photosynthetic organisms.

  4. Solar-driven hydrogen production in green algae.

    Science.gov (United States)

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

    2011-01-01

    The twin problems of energy security and global warming make hydrogen an attractive alternative to traditional fossil fuels with its combustion resulting only in the release of water vapor. Biological hydrogen production represents a renewable source of the gas and can be performed by a diverse range of microorganisms from strict anaerobic bacteria to eukaryotic green algae. Compared to conventional methods for generating H(2), biological systems can operate at ambient temperatures and pressures without the need for rare metals and could potentially be coupled to a variety of biotechnological processes ranging from desalination and waste water treatment to pharmaceutical production. Photobiological hydrogen production by microalgae is particularly attractive as the main inputs for the process (water and solar energy) are plentiful. This chapter focuses on recent developments in solar-driven H(2) production in green algae with emphasis on the model organism Chlamydomonas reinhardtii. We review the current methods used to achieve sustained H(2) evolution and discuss possible approaches to improve H(2) yields, including the optimization of culturing conditions, reducing light-harvesting antennae and targeting auxiliary electron transport and fermentative pathways that compete with the hydrogenase for reductant. Finally, industrial scale-up is discussed in the context of photobioreactor design and the future prospects of the field are considered within the broader context of a biorefinery concept. Copyright © 2011 Elsevier Inc. All rights reserved.

  5. Microbial Community Analysis of Colored Snow from an Alpine Snowfield in Northern Japan Reveals the Prevalence of Betaproteobacteria with Snow Algae.

    Science.gov (United States)

    Terashima, Mia; Umezawa, Kazuhiro; Mori, Shoichi; Kojima, Hisaya; Fukui, Manabu

    2017-01-01

    Psychrophilic algae blooms can be observed coloring the snow during the melt season in alpine snowfields. These algae are important primary producers on the snow surface environment, supporting the microbial community that coexists with algae, which includes heterotrophic bacteria and fungi. In this study, we analyzed the microbial community of green and red-colored snow containing algae from Mount Asahi, Japan. We found that Chloromonas spp. are the dominant algae in all samples analyzed, and Chlamydomonas is the second-most abundant genus in the red snow. For the bacterial community profile, species belonging to the subphylum Betaproteobacteria were frequently detected in both green and red snow, while members of the phylum Bacteroidetes were also prominent in red snow. Furthermore, multiple independently obtained strains of Chloromonas sp. from inoculates of red snow resulted in the growth of Betaproteobacteria with the alga and the presence of bacteria appears to support growth of the xenic algal cultures under laboratory conditions. The dominance of Betaproteobacteria in algae-containing snow in combination with the detection of Chloromonas sp. with Betaproteobacteria strains suggest that these bacteria can utilize the available carbon source in algae-rich environments and may in turn promote algal growth.

  6. Determination of Volatile Compounds in Four Commercial Samples of Japanese Green Algae Using Solid Phase Microextraction Gas Chromatography Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Masayoshi Yamamoto

    2014-01-01

    Full Text Available Green algae are of great economic importance. Seaweed is consumed fresh or as seasoning in Japan. The commercial value is determined by quality, color, and flavor and is also strongly influenced by the production area. Our research, based on solid phase microextraction gas chromatography mass spectrometry (SPME-GC-MS, has revealed that volatile compounds differ intensely in the four varieties of commercial green algae. Accordingly, 41 major volatile compounds were identified. Heptadecene was the most abundant compound from Okayama (Ulva prolifera, Tokushima (Ulva prolifera, and Ehime prefecture (Ulva linza. Apocarotenoids, such as ionones, and their derivatives were prominent volatiles in algae from Okayama (Ulva prolifera and Tokushima prefecture (Ulva prolifera. Volatile, short chained apocarotenoids are among the most potent flavor components and contribute to the flavor of fresh, processed algae, and algae-based products. Benzaldehyde was predominant in seaweed from Shizuoka prefecture (Monostroma nitidum. Multivariant statistical analysis (PCA enabled simple discrimination of the samples based on their volatile profiles. This work shows the potential of SPME-GC-MS coupled with multivariant analysis to discriminate between samples of different geographical and botanical origins and form the basis for development of authentication methods of green algae products, including seasonings.

  7. Determination of volatile compounds in four commercial samples of Japanese green algae using solid phase microextraction gas chromatography mass spectrometry.

    Science.gov (United States)

    Yamamoto, Masayoshi; Baldermann, Susanne; Yoshikawa, Keisuke; Fujita, Akira; Mase, Nobuyuki; Watanabe, Naoharu

    2014-01-01

    Green algae are of great economic importance. Seaweed is consumed fresh or as seasoning in Japan. The commercial value is determined by quality, color, and flavor and is also strongly influenced by the production area. Our research, based on solid phase microextraction gas chromatography mass spectrometry (SPME-GC-MS), has revealed that volatile compounds differ intensely in the four varieties of commercial green algae. Accordingly, 41 major volatile compounds were identified. Heptadecene was the most abundant compound from Okayama (Ulva prolifera), Tokushima (Ulva prolifera), and Ehime prefecture (Ulva linza). Apocarotenoids, such as ionones, and their derivatives were prominent volatiles in algae from Okayama (Ulva prolifera) and Tokushima prefecture (Ulva prolifera). Volatile, short chained apocarotenoids are among the most potent flavor components and contribute to the flavor of fresh, processed algae, and algae-based products. Benzaldehyde was predominant in seaweed from Shizuoka prefecture (Monostroma nitidum). Multivariant statistical analysis (PCA) enabled simple discrimination of the samples based on their volatile profiles. This work shows the potential of SPME-GC-MS coupled with multivariant analysis to discriminate between samples of different geographical and botanical origins and form the basis for development of authentication methods of green algae products, including seasonings.

  8. Interspecific variation in total phenolic content in temperate brown algae

    Directory of Open Access Journals (Sweden)

    Anna Maria Mannino

    2017-09-01

    Full Text Available Marine algae synthesize secondary metabolites such as polyphenols that function as defense and protection mechanisms. Among brown algae, Fucales and Dictyotales (Phaeophyceae contain the highest levels of phenolic compounds, mainly phlorotannins, that play multiple roles. Four temperate brown algae (Cystoseira amentacea, Cystoseira compressa, Dictyopteris polypodioides and Padina pavonica were studied for total phenolic contents. Total phenolic content was determined colorimetrically with the Folin-Ciocalteu reagent. Significant differences in total phenolic content were observed between leathery and sheetlike algae and also within each morphological group. Among the four species, the sheet-like alga D. polypodioides, living in the upper infralittoral zone, showed the highest concentration of phenolic compounds. These results are in agreement with the hypothesis that total phenolic content in temperate brown algae is influenced by a combination of several factors, such as growth form, depth, and exposition to solar radiation.

  9. Algae to Economically Viable Low-Carbon-Footprint Oil.

    Science.gov (United States)

    Bhujade, Ramesh; Chidambaram, Mandan; Kumar, Avnish; Sapre, Ajit

    2017-06-07

    Algal oil as an alternative to fossil fuel has attracted attention since the 1940s, when it was discovered that many microalgae species can produce large amounts of lipids. Economics and energy security were the motivational factors for a spurt in algae research during the 1970s, 1990s, and early 2000s. Whenever crude prices declined, research on algae stopped. The scenario today is different. Even given low and volatile crude prices ($30-$50/barrel), interest in algae continues all over the world. Algae, with their cure-all characteristics, have the potential to provide sustainable solutions to problems in the energy-food-climate nexus. However, after years of effort, there are no signs of algae-to-biofuel technology being commercialized. This article critically reviews past work; summarizes the current status of the technology; and based on the lessons learned, provides a balanced perspective on a potential path toward commercialization of algae-to-oil technology.

  10. Physical characteristic of brown algae (Phaeophyta from madura strait as irreversible hydrocolloid impression material

    Directory of Open Access Journals (Sweden)

    Prihartini Widiyanti

    2012-09-01

    Full Text Available Background: Brown algae is a raw material for producing natrium alginates. One type of brown algae is Sargassum sp, a member of Phaeophyta division. Sargassum sp could be found in Madura strait Indonesia. Natrium alginate can be extracted from Sargassum sp. The demand of alginate in Indonesia is mainly fulfilled from abroad, meanwhile Sargassum sp is abundantly available. Purpose: The purpose of study were to explore the potency of brown alga Sargassum sp from Madura strait as hydrocolloid impression material and to examine its physical characteristic. Methods: The methods of research including extraction natrium alginate from Sargassum sp, synthesis of dental impression material and the test of porosity, density, viscosity, and water content of impression material which fulfilled the standard of material used in clinical application in dentistry. Results: Extraction result of Sargassum sp was natrium alginate powder with cream colour, odorless, and water soluble. The water content of natrium alginate was 21.64% and the viscosity was 0.7 cPs. The best porosity result in the sample with the addition of trinatrium phosphate 4% was 3.61%. Density value of impression material was 3 gr/cm3. Conclusion: The research suggested that brown algae Sargassum sp from Madura strait is potential as hydrocolloid impression material, due to its physical properties which close to dental impression material, but still need further research to optimize the physical characteristic.Latar belakang: Alga coklat adalah sumber bahan baku material natrium alginat. Salah satu jenis alga coklat adalah Sargassum sp yang merupakan anggota divisi Phaeophyta. Sargassum sp dapat ditemukan di Selat Madura Indonesia. Natrium alginat dapat diekstraksi dari Sargassum sp. Kebutuhan akan bahan ini di Indonesia sebagian besar dipenuhi dari impor, padahal ketersediaan Sargassum sp di Indonesia sangat melimpah. Tujuan: Penelitian ini bertujuan untuk mengeksplorasi potensi alga coklat

  11. Production and characterization of algae extract from Chlamydomonas reinhardtii

    Directory of Open Access Journals (Sweden)

    Weston Kightlinger

    2014-01-01

    Conclusions: This study showed that algae extract derived from C. reinhardtii is similar, if not superior, to commercially available yeast extract in nutrient content and effects on the growth and metabolism of E. coli and S. cerevisiae. Bacto™ yeast extract is valued at USD $0.15–0.35 per gram, if algae extract was sold at similar prices, it would serve as a high-value co-product in algae-based fuel processes.

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

    Science.gov (United States)

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

    2015-12-01

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

  13. Genome Annotation and Transcriptomics of Oil-Producing Algae

    Science.gov (United States)

    2015-03-16

    AFRL-OSR-VA-TR-2015-0103 GENOME ANNOTATION AND TRANSCRIPTOMICS OF OIL-PRODUCING ALGAE Sabeeha Merchant UNIVERSITY OF CALIFORNIA LOS ANGELES Final...2010 To 12-31-2014 4. TITLE AND SUBTITLE GENOME ANNOTATION AND TRANSCRIPTOMICS OF OIL-PRODUCING ALGAE 5a. CONTRACT NUMBER FA9550-10-1-0095 5b...NOTES 14. ABSTRACT Most algae accumulate triacylglycerols (TAGs) when they are starved for essential nutrients like N, S, P (or Si in the case of some

  14. Biosorption: An Interplay between Marine Algae and Potentially Toxic Elements—A Review

    Science.gov (United States)

    Bilal, Muhammad; Rasheed, Tahir; Raza, Ali; Nabeel, Faran

    2018-01-01

    In recent decades, environmental pollution has emerged as a core issue, around the globe, rendering it of fundamental concern to eco-toxicologists, environmental biologists, eco-chemists, pathologists, and researchers from other fields. The dissolution of polluting agents is a leading cause of environmental pollution of all key spheres including the hydrosphere, lithosphere, and biosphere, among others. The widespread occurrence of various pollutants including toxic heavy metals and other emerging hazardous contaminants is a serious concern. With increasing scientific knowledge, socioeconomic awareness, human health problems, and ecological apprehensions, people are more concerned about adverse health outcomes. Against this background, several removal methods have been proposed and implemented with the aim of addressing environmental pollution and sustainable and eco-friendly development. Among them, the biosorption of pollutants using naturally inspired sources, e.g., marine algae, has considerable advantages. In the past few years, marine algae have been extensively studied due to their natural origin, overall cost-effective ratio, and effectiveness against a broader pollutant range; thus, they are considered a potential alternative to the conventional methods used for environmental decontamination. Herein, an effort has been made to highlight the importance of marine algae as naturally inspired biosorbents and their role in biosorption. Biosorption mechanisms and factors affecting biosorption activities are also discussed in this review. The utilization of marine algae as a biosorbent for the removal of numerous potentially toxic elements has also been reviewed. PMID:29463058

  15. Biosorption: An Interplay between Marine Algae and Potentially Toxic Elements-A Review.

    Science.gov (United States)

    Bilal, Muhammad; Rasheed, Tahir; Sosa-Hernández, Juan Eduardo; Raza, Ali; Nabeel, Faran; Iqbal, Hafiz M N

    2018-02-19

    In recent decades, environmental pollution has emerged as a core issue, around the globe, rendering it of fundamental concern to eco-toxicologists, environmental biologists, eco-chemists, pathologists, and researchers from other fields. The dissolution of polluting agents is a leading cause of environmental pollution of all key spheres including the hydrosphere, lithosphere, and biosphere, among others. The widespread occurrence of various pollutants including toxic heavy metals and other emerging hazardous contaminants is a serious concern. With increasing scientific knowledge, socioeconomic awareness, human health problems, and ecological apprehensions, people are more concerned about adverse health outcomes. Against this background, several removal methods have been proposed and implemented with the aim of addressing environmental pollution and sustainable and eco-friendly development. Among them, the biosorption of pollutants using naturally inspired sources, e.g., marine algae, has considerable advantages. In the past few years, marine algae have been extensively studied due to their natural origin, overall cost-effective ratio, and effectiveness against a broader pollutant range; thus, they are considered a potential alternative to the conventional methods used for environmental decontamination. Herein, an effort has been made to highlight the importance of marine algae as naturally inspired biosorbents and their role in biosorption. Biosorption mechanisms and factors affecting biosorption activities are also discussed in this review. The utilization of marine algae as a biosorbent for the removal of numerous potentially toxic elements has also been reviewed.

  16. Cryptochrome photoreceptors in green algae: Unexpected versatility of mechanisms and functions.

    Science.gov (United States)

    Kottke, Tilman; Oldemeyer, Sabine; Wenzel, Sandra; Zou, Yong; Mittag, Maria

    2017-10-01

    Green algae have a highly complex and diverse set of cryptochrome photoreceptor candidates including members of the following subfamilies: plant, plant-like, animal-like, DASH and cryptochrome photolyase family 1 (CPF1). While some green algae encode most or all of them, others lack certain members. Here we present an overview about functional analyses of so far investigated cryptochrome photoreceptors from the green algae Chlamydomonas reinhardtii (plant and animal-like cryptochromes) and Ostreococcus tauri (CPF1) with regard to their biological significance and spectroscopic properties. Cryptochromes of both algae have been demonstrated recently to be involved to various extents in circadian clock regulation and in Chlamydomonas additionally in life cycle control. Moreover, CPF1 even performs light-driven DNA repair. The plant cryptochrome and CPF1 are UVA/blue light receptors, whereas the animal-like cryptochrome responds to almost the whole visible spectrum including red light. Accordingly, plant cryptochrome, animal-like cryptochrome and CPF1 differ fundamentally in their structural response to light as revealed by their visible and infrared spectroscopic signatures, and in the role of the flavin neutral radical acting as dark form or signaling state. Copyright © 2017 Elsevier GmbH. All rights reserved.

  17. Biosorption: An Interplay between Marine Algae and Potentially Toxic Elements—A Review

    Directory of Open Access Journals (Sweden)

    Muhammad Bilal

    2018-02-01

    Full Text Available In recent decades, environmental pollution has emerged as a core issue, around the globe, rendering it of fundamental concern to eco-toxicologists, environmental biologists, eco-chemists, pathologists, and researchers from other fields. The dissolution of polluting agents is a leading cause of environmental pollution of all key spheres including the hydrosphere, lithosphere, and biosphere, among others. The widespread occurrence of various pollutants including toxic heavy metals and other emerging hazardous contaminants is a serious concern. With increasing scientific knowledge, socioeconomic awareness, human health problems, and ecological apprehensions, people are more concerned about adverse health outcomes. Against this background, several removal methods have been proposed and implemented with the aim of addressing environmental pollution and sustainable and eco-friendly development. Among them, the biosorption of pollutants using naturally inspired sources, e.g., marine algae, has considerable advantages. In the past few years, marine algae have been extensively studied due to their natural origin, overall cost-effective ratio, and effectiveness against a broader pollutant range; thus, they are considered a potential alternative to the conventional methods used for environmental decontamination. Herein, an effort has been made to highlight the importance of marine algae as naturally inspired biosorbents and their role in biosorption. Biosorption mechanisms and factors affecting biosorption activities are also discussed in this review. The utilization of marine algae as a biosorbent for the removal of numerous potentially toxic elements has also been reviewed.

  18. Accumulation of 210Po by benthic marine algae

    International Nuclear Information System (INIS)

    Gouvea, R.C.; Branco, M.E.C.; Santos, P.L.

    1988-01-01

    The accumulation of polonium 210 Po by various species of benthic marine seaweeds collected from 4 different points on the coast of Rio de Janeiro, showed variations by species and algal groups. The highest value found was in red alga, Plocamium brasiliensis followed by other organisms of the same group. In the group of the brown alga, the specie Sargassum stenophylum was outstanding. The Chlorophyta presented the lowest content of 210 Po. The algae collected in open sea, revealed greater concentration factors of 210 Po than the same species living in bays. The siliceous residue remaining after mineralization of the algae did not interfere with the detection of polonium. (author)

  19. Importance of algae oil as a source of biodiesel

    International Nuclear Information System (INIS)

    Demirbas, Ayhan; Fatih Demirbas, M.

    2011-01-01

    Algae are the fastest-growing plants in the world. Industrial reactors for algal culture are open ponds, photobioreactors and closed systems. Algae are very important as a biomass source. Algae will some day be competitive as a source for biofuel. Different species of algae may be better suited for different types of fuel. Algae can be grown almost anywhere, even on sewage or salt water, and does not require fertile land or food crops, and processing requires less energy than the algae provides. Algae can be a replacement for oil based fuels, one that is more effective and has no disadvantages. Algae are among the fastest-growing plants in the world, and about 50% of their weight is oil. This lipid oil can be used to make biodiesel for cars, trucks, and airplanes. Microalgae have much faster growth-rates than terrestrial crops. the per unit area yield of oil from algae is estimated to be from 20,000 to 80,000 l per acre, per year; this is 7-31 times greater than the next best crop, palm oil. The lipid and fatty acid contents of microalgae vary in accordance with culture conditions. Most current research on oil extraction is focused on microalgae to produce biodiesel from algal oil. Algal-oil processes into biodiesel as easily as oil derived from land-based crops.

  20. Method and apparatus for lysing and processing algae

    Science.gov (United States)

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

    2013-03-05

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

  1. Chloroplast division checkpoint in eukaryotic algae

    Science.gov (United States)

    Sumiya, Nobuko; Fujiwara, Takayuki; Era, Atsuko; Miyagishima, Shin-ya

    2016-01-01

    Chloroplasts evolved from a cyanobacterial endosymbiont. It is believed that the synchronization of endosymbiotic and host cell division, as is commonly seen in existing algae, was a critical step in establishing the permanent organelle. Algal cells typically contain one or only a small number of chloroplasts that divide once per host cell cycle. This division is based partly on the S-phase–specific expression of nucleus-encoded proteins that constitute the chloroplast-division machinery. In this study, using the red alga Cyanidioschyzon merolae, we show that cell-cycle progression is arrested at the prophase when chloroplast division is blocked before the formation of the chloroplast-division machinery by the overexpression of Filamenting temperature-sensitive (Fts) Z2-1 (Fts72-1), but the cell cycle progresses when chloroplast division is blocked during division-site constriction by the overexpression of either FtsZ2-1 or a dominant-negative form of dynamin-related protein 5B (DRP5B). In the cells arrested in the prophase, the increase in the cyclin B level and the migration of cyclin-dependent kinase B (CDKB) were blocked. These results suggest that chloroplast division restricts host cell-cycle progression so that the cell cycle progresses to the metaphase only when chloroplast division has commenced. Thus, chloroplast division and host cell-cycle progression are synchronized by an interactive restriction that takes place between the nucleus and the chloroplast. In addition, we observed a similar pattern of cell-cycle arrest upon the blockage of chloroplast division in the glaucophyte alga Cyanophora paradoxa, raising the possibility that the chloroplast division checkpoint contributed to the establishment of the permanent organelle. PMID:27837024

  2. Interactions between arsenic species and marine algae

    Energy Technology Data Exchange (ETDEWEB)

    Sanders, J.G.

    1978-01-01

    The arsenic concentration and speciation of marine algae varies widely, from 0.4 to 23 ng.mg/sup -1/, with significant differences in both total arsenic content and arsenic speciation occurring between algal classes. The Phaeophyceae contain more arsenic than other algal classes, and a greater proportion of the arsenic is organic. The concentration of inorganic arsenic is fairly constant in macro-algae, and may indicate a maximum level, with the excess being reduced and methylated. Phytoplankton take up As(V) readily, and incorporate a small percentage of it into the cell. The majority of the As(V) is reduced, methylated, and released to the surrounding media. The arsenic speciation in phytoplankton and Valonia also changes when As(V) is added to cultures. Arsenate and phosphate compete for uptake by algal cells. Arsenate inhibits primary production at concentrations as low as 5 ..mu..g.1/sup -1/ when the phosphate concentration is low. The inhibition is competitive. A phosphate enrichment of > 0.3 ..mu..M alleviates this inhibition; however, the As(V) stress causes an increase in the cell's phosphorus requirement. Arsenite is also toxic to phytoplankton at similar concentrations. Methylated arsenic species did not affect cell productivity, even at concentrations of 25 ..mu..g.1/sup -1/. Thus, the methylation of As(V) by the cell produces a stable, non-reactive compound which is nontoxic. The uptake and subsequent reduction and methylation of As(V) is a significant factor in determining the arsenic biogeochemistry of productive systems, and also the effect that the arsenic may have on algal productivity. Therefore, the role of marine algae in determining the arsenic speciation of marine systems cannot be ignored. (ERB)

  3. Snow algae and lichen algae differ in their resistance to freezing temperature: An ice nucleation study

    Czech Academy of Sciences Publication Activity Database

    Hajek, J.; Kvíderová, Jana; Worland, R.; Barták, M.; Elster, Josef; Vaczi, P.

    2009-01-01

    Roč. 48, č. 4 (2009), s. 37-38 ISSN 0031-8884. [International Phycological Congress /9./. 02.08.2009-08.08.2009, Tokyo] R&D Projects: GA AV ČR IAA600050702; GA AV ČR KJB601630808 Institutional research plan: CEZ:AV0Z60050516 Keywords : ice nucleation * algae * freezing Subject RIV: EF - Botanics

  4. Ammonium removal using algae-bacteria consortia: the effect of ammonium concentration, algae biomass, and light.

    Science.gov (United States)

    Jia, Huijun; Yuan, Qiuyan

    2018-04-01

    In this study, the effects of ammonium nitrogen concentration, algae biomass concentration, and light conditions (wavelength and intensity) on the ammonium removal efficiency of algae-bacteria consortia from wastewater were investigated. The results indicated that ammonium concentration and light intensity had a significant impact on nitrification. It was found that the highest ammonia concentration (430 mg N/L) in the influent resulted in the highest ammonia removal rate of 108 ± 3.6 mg N/L/days, which was two times higher than the influent with low ammonia concentration (40 mg N/L). At the lowest light intensity of 1000 Lux, algae biomass concentration, light wavelength, and light cycle did not show a significant effect on the performance of algal-bacterial consortium. Furthermore, the ammonia removal rate was approximately 83 ± 1.0 mg N/L/days, which was up to 40% faster than at the light intensity of 2500 Lux. It was concluded that the algae-bacteria consortia can effectively remove nitrogen from wastewater and the removal performance can be stabilized and enhanced using the low light intensity of 1000 Lux that is also a cost-effective strategy.

  5. Toxicity of chlorinated benzenes to marine algae

    Science.gov (United States)

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

    1997-12-01

    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: MCBNannochloropsis 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.

  6. Diterpenes from the Brown Alga Dictyota crenulata

    Directory of Open Access Journals (Sweden)

    Valéria Laneuville Teixeira

    2008-06-01

    Full Text Available The crude extract of the Brazilian brown alga Dictyota crenulata was analyzed by NMR spectroscopy and HRGC-MS techniques. Seven diterpenes were identified: pachydictyol A, dictyodial, 4β-hydroxydictyodial A, 4β-acetoxydictyodial A, isopachydictyol A, dictyol C and dictyotadiol. Xeniane diterpenes have previously been found in D. crenulata from the Pacific Ocean. The results characterize D. crenulata as a species that provides prenylated guaiane (group I and xeniane diterpenes (group III, thus making it a new source of potential antiviral products.

  7. Hypopigmenting Effects of Brown Algae-Derived Phytochemicals: A Review on Molecular Mechanisms.

    Science.gov (United States)

    Azam, Mohammed Shariful; Choi, Jinkyung; Lee, Min-Sup; Kim, Hyeung-Rak

    2017-09-24

    There is a rapid increase in the demand for natural hypopigmenting agents from marine sources for cosmeceutical and pharmaceutical applications. Currently, marine macroalgae are considered as a safe and effective source of diverse bioactive compounds. Many research groups are exploring marine macroalgae to discover and characterize novel compounds for cosmeceutical, nutraceutical, and pharmaceutical applications. Many types of bioactive secondary metabolites from marine algae, including phlorotannins, sulfated polysaccharides, carotenoids, and meroterpenoids, have already been documented for their potential applications in the pharmaceutical industry. Among these metabolites, phlorotannins from brown algae have been widely screened for their pharmaceutical and hypopigmenting effects. Unfortunately, the majority of these articles did not have detailed investigations on molecular targets, which is critical to fulfilling the criteria for their cosmeceutical and pharmaceutical use. Very recently, a few meroterpenoids have been discovered from Sargassum sp., with the examination of their anti-melanogenic properties and mechanisms. Despite the scarcity of in vivo and clinical investigations of molecular mechanistic events of marine algae-derived hypopigmenting agents, identifying the therapeutic targets and their validation in humans has been a major challenge for future studies. In this review, we focused on available data representing molecular mechanisms underlying hypopigmenting properties of potential marine brown alga-derived compounds.

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

    International Nuclear Information System (INIS)

    Zbikowski, Radoslaw; Szefer, Piotr; Latala, Adam

    2006-01-01

    The concentrations of heavy metals (Cd, Cu, Ni, Pb, Zn and Mn) and macroelements (K, Na, Ca and Mg) were determined in green alga Enteromorpha sp. from the coastal zone of the southern Baltic including Gulf of Gdansk and Vistula Lagoon in 2000-2003. In order to estimate the degree of accumulation of each element by the green alga, concentration and discrimination factors (CFs) with respect to seawater were calculated. The results of factor analysis (FA) and ANOVA clearly indicate geographical differences between concentrations of chemical elements. Enteromorpha sp. from Vistula Lagoon and the southern Baltic exhibited higher levels of Mn and Ni, and Na and K, respectively. Anthropogenic impact of Cu, Pb and Zn, possibly originated from municipal sewage, was identified in alga samples collected in the Gulf of Gdansk, especially in the vicinity of Gdynia. From comparison our data with those published earlier results that Pb content in Enteromorpha sp. from the Gulf of Gdansk decreased within 1978-2003 reflecting reducing use of leaded petrol in Baltic countries in this period. The alga Enteromorpha sp. can be used for biomonitoring surveys of metal contaminants in coastal areas of the Baltic Sea. - Enteromorpha sp. can be used as efficient biomonitor for chemical elements in coastal areas of the Baltic Sea

  9. Larval settlement preferences of Acropora palmata and Montastraea faveolata in response to diverse red algae

    Science.gov (United States)

    Ritson-Williams, R.; Arnold, S. N.; Paul, V. J.; Steneck, R. S.

    2014-03-01

    Settlement specificity can regulate recruitment but remains poorly understood for coral larvae. We studied larvae of the corals, Acropora palmata and Montastraea faveolata, to determine their rates of settlement and metamorphosis in the presence of ten species of red algae, including eight species of crustose coralline algae, one geniculated coralline and one encrusting peyssonnelid. Twenty to forty percent of larvae of A. palmata settled on coralline surfaces of Hydrolithon boergesenii, Lithoporella atlantica, Neogoniolithon affine, and Titanoderma prototypum, whereas none settled and metamorphosed on Neogoniolithon mamillare. Larvae of M. faveolata had 13-25 % settlement onto the surface of Amphiroa tribulus, H. boergesenii, N. affine, N. munitum, and T. prototypum, but had no settlement on the surface of N. mamillare, Porolithon pachydermum, and a noncoralline crust Peyssonnelia sp. Some of these algal species were common on Belizean reefs, but the species that induced the highest rates of larval settlement and metamorphosis tended to be rare and primarily found in low-light environments. The shallow coral, A. palmata, and the deeper coral, M. faveolata, both had increased larval settlement rates in the presence of only a few species of red algae found at deeper depths suggesting that patterns of coral distribution can only sometimes be related to the distribution of red algae species.

  10. Genomic insights from the oleaginous model alga Nannochloropsis gaditana.

    Science.gov (United States)

    Jinkerson, Robert E; Radakovits, Randor; Posewitz, Matthew C

    2013-01-01

    Nannochloropsis species have emerged as leading phototrophic microorganisms for the production of biofuels. Several isolates produce large quantities of triacylglycerols, grow rapidly, and can be cultivated at industrial scales. Recently, the mitochondrial, plastid and nuclear genomes of Nannochloropsis gaditana were sequenced. Genomic interrogation revealed several key features that likely facilitate the oleaginous phenotype observed in Nannochloropsis, including an over-representation of genes involved in lipid biosynthesis. Here we present additional analyses on gene orientation, vitamin B12 requiring enzymes, the acetyl-CoA metabolic node, and codon usage in N. gaditana. Nuclear genome transformation methods are established with exogenous DNA integration occurring via either random incorporation or by homologous recombination, making Nannochloropsis amenable to both forward and reverse genetic engineering. Completion of a draft genomic sequence, establishment of transformation techniques, and robust outdoor growth properties have positioned Nannochloropsis as a new model alga with significant potential for further development into an integrated photons-to-fuel production platform.

  11. The Occurrence of Hormesis in Plants and Algae

    DEFF Research Database (Denmark)

    Cedergreen, Nina; Streibig, Jens C; Kudsk, Per

    2007-01-01

    This paper evaluated the frequency, magnitude and dose/concentration range of hormesis in four species: The aquatic plant Lemna minor, the micro-alga Pseudokirchneriella subcapitata and the two terrestrial plants Tripleurospermum inodorum and Stellaria media exposed to nine herbicides and one...... compared to relative growth rates. Evaluating hormesis for relative growth rates for all species showed that 25% to 76% of the curves for each species had treatments above 105% of the control. Fitting the data with a dose-response model including a parameter for hormesis showed that the average growth...... increase ranged from 9±1% to 16±16% of the control growth rate, while if measured on a dry weight basis the response increase was 38±13% and 43±23% for the two terrestrial species. Hormesis was found in >70% of the curves with the herbicides glyphosate and metsulfuron-methyl, and in >50% of the curves...

  12. Energy from algae using microbial fuel cells

    KAUST Repository

    Velasquez-Orta, Sharon B.

    2009-08-15

    Bioelectricity production froma phytoplankton, Chlorella vulgaris, and a macrophyte, Ulva lactuca was examined in single chamber microbial fuel cells (MFCs). MFCs were fed with the two algae (as powders), obtaining differences in energy recovery, degradation efficiency, and power densities. C. vulgaris produced more energy generation per substrate mass (2.5 kWh/kg), but U. lactuca was degraded more completely over a batch cycle (73±1% COD). Maximum power densities obtained using either single cycle or multiple cycle methods were 0.98 W/m2 (277 W/m3) using C. vulgaris, and 0.76 W/m2 (215 W/m3) using U. lactuca. Polarization curves obtained using a common method of linear sweep voltammetry (LSV) overestimated maximum power densities at a scan rate of 1 mV/s. At 0.1 mV/s, however, the LSV polarization data was in better agreement with single- and multiple-cycle polarization curves. The fingerprints of microbial communities developed in reactors had only 11% similarity to inocula and clustered according to the type of bioprocess used. These results demonstrate that algae can in principle, be used as a renewable source of electricity production in MFCs. © 2009 Wiley Periodicals, Inc.

  13. Isolation and Characterization of Blue Green Algae from Egyptian ...

    African Journals Online (AJOL)

    meldemellawy

    2014-02-20

    Feb 20, 2014 ... aminotransferase (AMT) domains of the mycE and ndaF genes (Jungblut et al., 2006) allowing detection of microcystin and nodularin-producing cyanobacteria. MATERIALS AND METHODS. Isolation and cultivation of blue green algae. Blue green algae had been isolated from soil of Rice field in river.

  14. Monetary value of the impacts of filamentous green algae on ...

    African Journals Online (AJOL)

    This paper presents estimates of the monetary value of the impact of eutrophication (algae) on commercial agriculture in two different catchments in South Africa. A production function approach is applied to estimate the monetary value of the impact of filamentous green algae on commercial agriculture in the Dwars River, ...

  15. Dissolved Air Flotation Process for Algae Removal | Mulaku ...

    African Journals Online (AJOL)

    This study investigated the performance of the Dissolved Air Flotation (DAF) process as an alternative to sedimentation for algae removal in surface water treatment in Kenya. Batch DAF experiments were carried out in the laboratory using algae laden surface water samples collected from the river and laboratory cultured ...

  16. Persistence and proliferation of some unicellular algae in drinking ...

    African Journals Online (AJOL)

    Drinking water systems have a complex structure and are characterised by the absence of light, the presence of disinfectants and by low levels of nutrients. Several kinds of bacteria, protozoa, algae and fungi can be found in tap water. Little is known about the ecology of algae in drinking water systems, although their ...

  17. Algae Cultivation for Carbon Capture and Utilization Workshop Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2017-05-01

    The Algae Cultivation for Carbon Capture and Utilization Workshop Summary Report summarizes a workshop hosted by the U.S. Department of Energy's Bioenergy Technologies Office on May 23–24, 2017, in Orlando, Florida. The event gathered stakeholder input through facilitated discussions focused on innovative technologies and business strategies for growing algae on waste carbon dioxide resources.

  18. Study on the effect of irradiation on algae by proteomics

    International Nuclear Information System (INIS)

    Choi, Jong Il; Yoon, Yo Han; Kim, Jae Hun

    2010-06-01

    Algae has been utilized as food material from long time ago, and recently newly recognized as functional materials and the source of bio-fuel. But, the study on the algae is just beginning and the study on protein expression and growth by the change of condition was not reported. In this study, the effect of radiation on the protein expression was investigated for the protection mechanisms and new genome source and furthermore, isolation of new mutant strains. To monitor the growth of algae, absorbance and FDA staining methods were developed and the content of lipid of algae species were measured. With these methods, the radiation sensitivity of algae species was determined. To investigate the proteome of algae, 2D-electrophoresis methods was applied. From the comparison of proteomes, the radiation specific expressed protein was identified as thioredoxin-h and its nucleotide sequences was defined. The expression of thioredoxin-h was further defined on the mRNA level. Also, the extract of algae species was analyzed for its antioxidant activity and polyphenolic content. The changes in antioxidant activity of extract by radiation was investigated. From the radiation experiments, mutant Spirogyra species having higher resistant against radical stress was obtained. The mutant strain has higher antioxidant activity. This results can provide the proteome date and mutation technology of algae and further contribute in the activation of fishery industry and national health enhancement

  19. EnAlgae Decision Support Toolset: model validation

    NARCIS (Netherlands)

    Kenny, Philip; Visser, de Chris; Skarka, Johannes; Sternberg, Kirstin; Schipperus, Roelof; Silkina, Alla; Ginnever, Naomi

    2015-01-01

    One of the drivers behind the EnAlgae project is recognising and addressing the need for increased availability of information about developments in applications of algae biotechnology for energy, particularly in the NW Europe area, where activity has been less intense than in other areas of the

  20. Evaluation of the activated carbon prepared from the algae ...

    African Journals Online (AJOL)

    Evaluation of the activated carbon prepared from the algae Gracilaria for the biosorption of Cu(II) from aqueous solutions. ... African Journal of Biotechnology ... This study shows the benefit of using activated carbon from marine red algae as a low cost sorbent for the removal of copper from aqueous solution wastewater.

  1. Potential of wastewater grown algae for biodiesel production and CO

    African Journals Online (AJOL)

    Potential of wastewater grown algae for biodiesel production and CO 2 sequestration. ... African Journal of Biotechnology ... Mixed algae sample showed the highest CO2 fixation rate, followed by Chlorella sp., Scenedesmus incrassatulus, Scenedesmus dimorphus and Chroococcus cohaerens (2.807, 1.627, 1.501, 1.270 ...

  2. Rare species of fungi parasiting on algae. III.

    Directory of Open Access Journals (Sweden)

    Joanna Z. Kadłubowska

    2014-08-01

    Full Text Available The investigations csrried out on algae revealed the following species of fungi from the order of Chytridialis Hawksworth et al. (1995 parasitizing on algae: Rhizophydium subgulosum, R. ganlosporum, R. planctonicum, Entophlyctis rhizina and Harpochytrium hedinii. These species arc new to Poland. The figure of resting spore of Entophlyctis rhizina is the fint graphic documentation of this species.

  3. Rare species of fungi parasiting on algae. III.

    OpenAIRE

    Joanna Z. Kadłubowska

    2014-01-01

    The investigations csrried out on algae revealed the following species of fungi from the order of Chytridialis Hawksworth et al. (1995) parasitizing on algae: Rhizophydium subgulosum, R. ganlosporum, R. planctonicum, Entophlyctis rhizina and Harpochytrium hedinii. These species arc new to Poland. The figure of resting spore of Entophlyctis rhizina is the fint graphic documentation of this species.

  4. Comparison Uptake of Cadmium (II from Aqueous Solution, onto Algae Brown Fucus Serratus and Cystoseira Indica

    Directory of Open Access Journals (Sweden)

    Naser Jafari

    2015-01-01

    Full Text Available The cadmium metal not only has detrimental effects on the nervous system, the kidneys, and the human fetus but is also lethal because of its carcinogenic effects. Biological absorption of cadmium has a number of advantages over conventional methods that include high removal efficiency for eliminating heavy metals from dilute solutions, availability and abundance of the required materials in nature, and reproducibility and reusability of the materials. In this study, the biosorption of cadmium (II ions onto the dry biomass of two brown algae, Cystoseira indica and Fucus serratus, was investigated. Cystoseira indica was collected from the coastal areas of the Oman Sea and Fucus serratus was collected from the coastal area of the Atlantic Ocean. The algae were first dried, washed three times with tap water, and finally washed with distilled water without ions before they were isolated in pieces 0.5-1.5 mm in diameter. In all the experiments, distilled water was used to which known amounts of cadmium were added before the algae were introduced into the solution. The metal ion concentrations in the solution were measured using the atomic absorption spectrophotometer before and after the metal came into contact with the algae. The optimum pH for the adsorption of cadmium was found to be 3/0 ± 5/6 and 3/0 ± 5/5 for Cystoseira indica and Fucus serratus, respectively. The maximum metal uptakes by both algae were observed in acidic pH conditions. The time required for the biosorption of the metal to reach equilibrium was 360 minutes for Cystoseira indica and 300 minutes Fucus serratus. The adsorption capacities for Cystoseira indica and Fucus serratus using the Langmuir isotherm were determined as 44/58 and 54/95 mg /g, respectively. Moreover, the functional groups involved in cadmium uptake in both algae were identified. Finally, the results of this study showed that Fucus serratus algae had a higher capacity for adsorbing cadmium ions than did

  5. Investigation about Role of Algae in Kazeroon Sasan Spring Odor

    Directory of Open Access Journals (Sweden)

    A Hamzeian

    2016-05-01

    Full Text Available Introduction: As odor for potable water is unpleasant for costumers, it needs to do researches for finding the reasons of odorous water. Sasan spring that is located in, near kazeroon city, Fars, Iran, is potable water resource for Kazeroon and Booshehr city and many other villages. Water in Sasan spring has the odor problem. With regards to important   role of algae on ado r problems in this study the role of algae on   odor was investigated. Methods: After regular sampling, the TON (threshold odor number was indicated and algae species was distinguished and the number of total algae and any species  of algae was numbers by microscopic direct numbering method .as the algae mass  is related to nitrogen and phosphor concentration, results of concentration Of nitrogen and phosphor in this spring that was examined regularity by water company was investigated and compared to concentration of these component that are need for algae growing.   Results: results shows that TON was in range  of 4.477 to 6.2 that indicated  oderous limit . Regression and diagram between TON and number of total algae showed the linear relationship. The concentration of nitrogen and phosphor, showed adequate condition for algal grow. Result of determination of algae species showed high population of Oscilatoria and Microcystis species, which are known as essential case of mold odor in water resources. Investigation on geological maps in the region around the Sasan spring, show alluvium source and is effected by surface part of it’s around land. Conclusion: because of the algae was determined as the essential cause of odor   in the spring, and algal growth is related to nutrients, and because of the surface pollution can penetrate in the alluvium lands around the spring, and effect the water in spring, so nutrient control and management is the essential way for odor control in the spring.

  6. Cultivation of phagotrophic algae with waste activated sludge as a fast approach to reclaim waste organics.

    Science.gov (United States)

    Li, Cong; Xiao, Suo; Ju, Lu-Kwang

    2016-03-15

    Substantial energy is reserved in waste activated sludge (WAS) organics but much of it is difficult to recover because the solid organics require long time to solubilize. In this work we introduced the new approach of recovering WAS organics into the biomass of phagotrophic algae. Phagotrophic algae have the unique ability to grow by ingesting insoluble organic particles including microbial cells. This phagotrophic ability renders the solubilization of WAS organics unnecessary and makes this approach remarkably fast. The approach consists of two stages: a short anaerobic digestion treatment followed by the algal growth on treated WAS. The short anaerobic digestion was exploited to release discrete bacteria from WAS flocs. Phagotrophic algae could then grow rapidly with the released bacteria as well as the solubilized nutrients in the treated WAS. The results showed that WAS organics could be quickly consumed by phagotrophic algae. Among all studied conditions the highest WAS volatile solids (VS) reduction was achieved with 72 h anaerobic digestion and 24 h algal growth. In this optimal process, 28% of WAS VS was reduced, and 41% and 20% of the reduced VS were converted into algal biomass and lipids, respectively. In comparison, only 18% WAS VS were reduced after the same time of aerobic digestion without algae addition. Through this approach, the amount of WAS organics requiring further treatment for final disposal is significantly reduced. With the production of significant amounts of algal biomass and lipids, WAS treatment is expected to be more economical and sustainable in material recycling. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Coralline algae elevate pH at the site of calcification under ocean acidification.

    Science.gov (United States)

    Cornwall, Christopher E; Comeau, Steeve; McCulloch, Malcolm T

    2017-10-01

    Coralline algae provide important ecosystem services but are susceptible to the impacts of ocean acidification. However, the mechanisms are uncertain, and the magnitude is species specific. Here, we assess whether species-specific responses to ocean acidification of coralline algae are related to differences in pH at the site of calcification within the calcifying fluid/medium (pH cf ) using δ 11 B as a proxy. Declines in δ 11 B for all three species are consistent with shifts in δ 11 B expected if B(OH) 4 - was incorporated during precipitation. In particular, the δ 11 B ratio in Amphiroa anceps was too low to allow for reasonable pH cf values if B(OH) 3 rather than B(OH) 4 - was directly incorporated from the calcifying fluid. This points towards δ 11 B being a reliable proxy for pH cf for coralline algal calcite and that if B(OH) 3 is present in detectable proportions, it can be attributed to secondary postincorporation transformation of B(OH) 4 - . We thus show that pH cf is elevated during calcification and that the extent is species specific. The net calcification of two species of coralline algae (Sporolithon durum, and Amphiroa anceps) declined under elevated CO 2 , as did their pH cf . Neogoniolithon sp. had the highest pH cf , and most constant calcification rates, with the decrease in pH cf being ¼ that of seawater pH in the treatments, demonstrating a control of coralline algae on carbonate chemistry at their site of calcification. The discovery that coralline algae upregulate pH cf under ocean acidification is physiologically important and should be included in future models involving calcification. © 2017 John Wiley & Sons Ltd.

  8. Endolithic algae of semi-desert sandstones: systematic, biogeographic and ecophysiologic investigations

    International Nuclear Information System (INIS)

    Bell, R.A.

    1986-01-01

    Investigations were conducted into the ecology of an unusual algal community in northern Arizona. These microorganisms are called endolithic algae because they occur beneath the surface of rocks. Eighteen taxa, including representatives of both eukaryotic and prokaryotic genera, were isolated from below the surface of eight sandstones in four semi-desert and cold temperate biomes of the Colorado Plateau. As the macroclimate of the area changes from cold temperature desert scrub to cold temperate forest the taxonomic composition of the endolithic algal communities shifts from domination by coccoid blue-green algae to domination by coccoid and sarcinoid green algae. The algal communities varied in generic composition, chlorophyll a content, and in their location within the different sandstones. Investigations into the microclimate of the endolithic algal zone in two adjacent but differently-colored sections (white and brown) of Coconino sandstone have demonstrated differences between the environment above the rock surface and that just beneath the surface. In seasonal samples of the Coconino sandstone, chlorophyll a content ranged from 50 to 100 mg x m -2 in the white rock and 8 to 45 mg x m -2 in the brown rock. Primary production (as measured by 14 CO 2 incorporation) displayed marked seasonal patterns that appear to be correlated to the environmental conditions within the rocks as opposed to those outside the rocks. The widespread distribution of certain algae in the endolithic habitats of the Colorado Plateau and their presence in rocks at quite distant locations suggests that the endolithic habitat may be utilized by algae whenever it provides more favorable conditions than the surrounding surfaces

  9. Desiccation stress and tolerance in green algae: consequences for ultrastructure, physiological and molecular mechanisms

    Science.gov (United States)

    Holzinger, Andreas; Karsten, Ulf

    2013-01-01

    Although most green algae typically occur in aquatic ecosystems, many species also live partly or permanently under aeroterrestrial conditions, where the cells are exposed to the atmosphere and hence regularly experience dehydration. The ability of algal cells to survive in an air-dried state is termed desiccation tolerance. The mechanisms involved in desiccation tolerance of green algae are still poorly understood, and hence the aim of this review is to summarize recent findings on the effects of desiccation and osmotic water loss. Starting from structural changes, physiological, and biochemical consequences of desiccation will be addressed in different green-algal lineages. The available data clearly indicate a range of strategies, which are rather different in streptophycean and non-streptophycean green algae. While members of the Trebouxiophyceae exhibit effective water loss-prevention mechanisms based on the biosynthesis and accumulation of particular organic osmolytes such as polyols, these compounds are so far not reported in representatives of the Streptophyta. In members of the Streptophyta such as Klebsormidium, the most striking observation is the appearance of cross-walls in desiccated samples, which are strongly undulating, suggesting a high degree of mechanical flexibility. This aids in maintaining structural integrity in the dried state and allows the cell to maintain turgor pressure for a prolonged period of time during the dehydration process. Physiological strategies in aeroterrestrial green algae generally include a rapid reduction of photosynthesis during desiccation, but also a rather quick recovery after rewetting, whereas aquatic species are sensitive to drying. The underlying mechanisms such as the affected molecular components of the photosynthetic machinery are poorly understood in green algae. Therefore, modern approaches based on transcriptomics, proteomics, and/or metabolomics are urgently needed to better understand the molecular

  10. Desiccation stress and tolerance in green algae: Consequences for ultrastructure, physiological and molecular mechanisms

    Directory of Open Access Journals (Sweden)

    Andreas eHolzinger

    2013-08-01

    Full Text Available Although most green algae typically occur in aquatic ecosystems, many species also live partly or permanently under aeroterrestrial conditions, where the cells are exposed to the atmosphere and hence regularly experience dehydration. The ability of algal cells to survive in an air-dried state is termed desiccation tolerance. The mechanisms involved in desiccation tolerance of green algae are still poorly understood, and hence the aim of this review is to summarize recent findings on the effects of desiccation and osmotic water loss. Starting from structural changes, physiological and biochemical consequences of desiccation will be addressed in different green-algal lineages. The available data clearly indicate a range of strategies, which are rather different in streptophycean and non-streptophycean green algae. For example, Trebouxiophyceae exhibit effective water loss-prevention mechanisms based on the biosynthesis and accumulation of particular organic osmolytes such as polyols, these compounds are so far not reported in representatives of the Streptophyta. In members of the Streptophyta such as Klebsormidium, the most striking observation is the appearance of cross-walls in desiccated samples, which are strongly undulating, suggesting a high degree of mechanical flexibility. This allows the cell to maintain turgor pressure for a prolonged period of time during the dehydration process. Physiological strategies in aeroterrestrial green algae generally include a rapid reduction of photosynthesis during desiccation, but also a rather quick recovery after rewetting, whereas aquatic species are sensitive to drying. The underlying mechanisms such as the affected molecular components of the photosynthetic machinery are poorly understood in green algae. Therefore, modern approaches based on transcriptomics, proteomics and/or metabolomics are urgently needed to better understand the molecular mechanisms involved in desiccation-stress physiology of

  11. Characterization of phosphorus forms in lake macrophytes and algae by solution (31)P nuclear magnetic resonance spectroscopy.

    Science.gov (United States)

    Feng, Weiying; Zhu, Yuanrong; Wu, Fengchang; Meng, Wei; Giesy, John P; He, Zhongqi; Song, Lirong; Fan, Mingle

    2016-04-01

    Debris from aquatic macrophytes and algae are important recycling sources of phosphorus (P), which can result in continuing blooms of algae by recycling bioavailable P in the eutrophic lakes. However, knowledge of forms of P in aquatic macrophytes and algae and their contribution to internal loads of P in lakes is limited. Without such knowledge, it is difficult to develop appropriate strategies to remediate and or restore aquatic ecosystems that have become eutrophic. Therefore, in this work, P was extracted from six types of aquatic macrophytes and algae collected from Tai Lake of China and characterized by use of solution (31)P-nuclear magnetic resonance (NMR) spectroscopy. When extracted by 0.5 M NaOH-25 mM EDTA, extraction recovery of total P(TP) and organic P(Po) exceeded 90 %. Concentrations of Po in algae and aquatic macrophytes were 5552 mg kg(-1) and 1005 mg kg(-1) and accounted for 56.0 and 47.2 % of TP, respectively. When Po, including condensed P, was characterized by solution (31)P-NMR Po in algae included orthophosphate monoesters (79.8 %), pyrophosphate (18.2 %), and orthophosphate diester (2.0 %), and Po in aquatic macrophytes included orthophosphate monoesters (90.3 %), pyrophosphate (4.2 %), and orthophosphate diester (5.5 %). Additionally, orthophosphate monoesters in algal debris mainly included β-glycerophosphate (44.1 %), α-glycerophosphate (13.5 %), and glucose 6-phosphate (13.5 %). Orthophosphate monoesters in aquatic macrophytes mainly included β-glycerophosphate (27.9 %), α-glycerophosphate (24.6 %), and adenosine 5' monophosphate (8.2 %). Results derived from this study will be useful in better understanding nutrient cycling, relevant eutrophication processes, and pollution control for freshwater lakes.

  12. Comparative Energetics of Carbon Storage Molecules in Green Algae

    Energy Technology Data Exchange (ETDEWEB)

    Laurens, Lieve M [National Renewable Energy Laboratory (NREL), Golden, CO (United States); McKie-Krisberg, Zaid M. [City University of New York; Huang, Andy [City University of New York; Polle, Jurgen E. W. [City University of New York

    2018-02-28

    Several members of the green algae possess the ability to produce lipids and/or high value compounds in significant quantities. While for several of these green algal species induction of increased lipid production has been shown, and cultivation of species for high value molecules occurs at production scale, the molecular mechanisms governing over-accumulation of molecules synthesized from isoprenoid precursors, carotenoids, for example, have received far less attention. Here, we present a calculation of the required ATP equivalencies per carbon atom and reducing power equivalencies as NADH/NADPH (NAD(P)H) per carbon atom for the isoprenoid molecules ..beta..-carotene (C40), astaxanthin (C40), and squalene (C30). We compared energetic requirements of carbohydrates, triacylglycerol, and isoprenoid molecules under a gradient of conditions of cellular stress. Our calculations revealed slightly less ATP and NAD(P)H equivalency per carbon atom between triacylglycerol and the three isoprenoid molecules. Based on our results, we propose that the driving force for differences in accumulation patterns of carotenoids vs. triacylglycerols in algal cells under stress is largely dependent on the presence and regulation of bypass mechanisms at metabolic junction bottlenecks, like pyruvate dehydrogenase (PDH), within particular species. We provide a discussion of several molecular mechanisms that may influence carbon partitioning within different groups of green algae, including metabolic inhibition through accumulation of specific substrates related to ATP and reducing equivalent production (NAD(P)H) as well as cellular compartmentalization. This work contributes to the ongoing discussion of cellular homeostatic regulation during stress, as well as the potential mechanisms driving long-term carbon storage as it relates to energy and redox states within the algal cell.

  13. Lack of susceptibility of transgenic mice carrying the human c-Ha-ras proto-oncogene (rasH2 mice) to phenolphthalein in a 6-month carcinogenicity study.

    Science.gov (United States)

    Koujitani, T; Yasuhara, K; Usui, T; Nomura, T; Onodera, H; Takagi, H; Hirose, M; Mitsumori, K

    2000-05-01

    Phenolphthalein has carcinogenic activity, causing malignant lymphomas in B6C3F1 mice at a dietary dose of 3000 ppm in a 2-year carcinogenicity study and in heterozygous p53-deficient female mice at the same dose in a 6-month study. To examine whether phenolphthalein carcinogenic potential can be detected in male and female transgenic (Tg) mice carrying the human c-Ha-ras gene (rasH2 mice) and their wild-type littermates (non-Tg mice), a diet containing 3000, 6000 or 12000 ppm was given for 6 months. Unequivocal induction of neoplastic lesions was not apparent, suggesting that rasH2 mice are resistant to the induction of malignant lymphomas by the treatment of phenolphthalein.

  14. Photoregulation of photosystem II activity mediated by cytoplasmic streaming in Chara and its relation to pH bands.

    Science.gov (United States)

    Bulychev, Alexander A; Komarova, Anna V

    2017-05-01

    Chloroplasts in vivo exposed to strong light export assimilates and excess reducing power to the cytoplasm for metabolic conversions and allocation to neighboring and distant organelles. The cytoplasmic streaming, being particularly fast in characean internodes, distributes the exported metabolites from brightly illuminated cell spots to light-limited regions, which is evident from the transient increase in chlorophyll fluorescence of shaded areas in response to illumination of distant cell regions situated upstream the liquid flow. It is not yet known whether long-distance communications between anchored chloroplasts are interfered by pH banding that commonly arises in characean internodes under the action of continuous or fluctuating light. In this study, microfluorometry, pH-microsensors, and local illumination were combined to examine long-distance transport and subsequent reentry of photosynthetic metabolites, including triose phosphates, into chloroplasts of cell regions producing external alkaline and acid bands. The lateral transmission of metabolic signals between distant chloroplasts was found to operate effectively in cell areas underlying acid zones but was almost fully blocked under alkaline zones. The rates of linear electron flow in chloroplasts of these regions were nearly equal under dim background light, but differed substantially at high light when availability of CO 2 , rather than irradiance, was the rate-limiting factor. Different productions of assimilates by chloroplasts underlying CO 2 -sufficient acid and CO 2 -deficient alkaline zones were a cause for contrasting manifestations of long-distance transport of photosynthetic metabolites. Nonuniform cytoplasmic pH in cells exhibiting pH bands might contribute to different activities of metabolic translocators under high and low pH zones. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Algae façade as green building method: application of algae as a method to meet the green building regulation

    Science.gov (United States)

    Poerbo, Heru W.; Martokusumo, Widjaja; Donny Koerniawan, M.; Aulia Ardiani, Nissa; Krisanti, Susan

    2017-12-01

    The Local Government of Bandung city has stipulated a Green Building regulation through the Peraturan Walikota Number 1023/2016. Signed by the mayor in October 2016, Bandung became the first city in Indonesia that put green building as mandatory requirement in the building permit (IMB) process. Green Building regulation is intended to have more efficient consumption of energy and water, improved indoor air quality, management of liquid and solid waste etc. This objective is attained through various design method in building envelope, ventilation and air conditioning system, lighting, indoor transportation system, and electrical system. To minimize energy consumption of buildings that have large openings, sun shading device is often utilized together with low-E glass panes. For buildings in hot humid tropical climate, this method reduces indoor air temperature and thus requires less energy for air conditioning. Indoor air quality is often done by monitoring the carbon dioxide levels. Application of algae as part of building system façade has recently been introduced as replacement of large glass surface in the building façade. Algae are not yet included in the green building regulation because it is relatively new. The research will investigate, with the help of the modelling process and extensive literature, how effective is the implementation of algae in building façade to reduce energy consumption and improve its indoor air quality. This paper is written based on the design of ITB Innovation Park as an ongoing architectural design-based research how the algae-integrated building façade affects the energy consumption.

  16. Antileishmanial properties of tropical marine algae extracts.

    Science.gov (United States)

    Freile-Pelegrin, Y; Robledo, D; Chan-Bacab, M J; Ortega-Morales, B O

    2008-07-01

    Aqueous and organic extracts of twenty-seven species of marine algae (14 species of Rhodophyta, 5 species of Phaeophyta and 8 species of Chlorophyta) collected from the Gulf of Mexico and Caribbean coast of the Yucatan Peninsula (Mexico) were evaluated for their antileishmanial in vitro activity against Leishmania mexicana promastigote forms. The cytotoxicity of these extracts was also assessed using brine shrimp. Organic extracts from Laurencia microcladia (Rhodophyta), Dictyota caribaea, Turbinaria turbinata and Lobophora variegata (Phaeophyta) possessed promising in vitro activity against L. mexicana promastigotes (LC(50) values ranging from 10.9 to 49.9 microg/ml). No toxicity of algal extracts against Artemia salina was observed with LC50 ranging from 119 to >or=1000 microg/ml. Further studies on bio-guided fractionation, isolation and characterization of pure compounds from these species as well as in vivo experiments are needed and are already in progress.

  17. An algae-covered alligator rests warily

    Science.gov (United States)

    2000-01-01

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

  18. Harmful impact of filamentous algae (Spirogyra sp. on juvenile crayfish

    Directory of Open Access Journals (Sweden)

    Ulikowski Dariusz

    2015-12-01

    Full Text Available The aim of this study was to determine the impact of filamentous algae on the growth and survival of juvenile narrow-clawed crayfish, Astacus leptodactylus (Esch., in rearing basins. Three stocking variants were used: A - basins with a layer of filamentous algae without imitation mineral substrate; B - basins with a layer of filamentous algae with imitation mineral substrate; C - basins without filamentous algae but with mineral substrate. The crayfish were reared from June 12 to October 10 under natural thermal conditions and fed a commercial feed. The results indicated that the presence of the filamentous algae did not have a statistically significant impact on the growth of the juvenile crayfish (P > 0.05. The presence of the filamentous algae had a strong negative impact on juvenile crayfish survival and stock biomass (P < 0.05. The layer of gravel and small stones that imitated the mineral substrate of natural aquatic basins somewhat neutralized the disadvantageous impact the filamentous algae had on the crayfish.

  19. A screening method for cardiovascular active compounds in marine algae.

    Science.gov (United States)

    Agatonovic-Kustrin, S; Kustrin, E; Angove, M J; Morton, D W

    2018-05-18

    The interaction of bioactive compounds from ethanolic extracts of selected marine algae samples, separated on chromatographic plates, with nitric/nitrous acid was investigated. The nature of bioactive compounds in the marine algae extracts was characterised using UV absorption spectra before and after reaction with diluted nitric acid, and from the characteristic colour reaction after derivatization with anisaldehyde. It was found that diterpenes from Dictyota dichotoma, an edible brown algae, and sterols from green algae Caulerpa brachypus, bind nitric oxide and may act as a nitric oxide carrier. Although the carotenoid fucoxanthin, found in all brown marine algae also binds nitric oxide, the bonds between nitrogen and the fucoxanthin molecule are much stronger. Further studies are required to evaluate the effects of diterpenes from Dictyota dichotoma and sterols from green algae Caulerpa brachypus to see if they have beneficial cardiovascular effects. The method reported here should prove useful in screening large numbers of algae species for compounds with cardiovascular activity. Copyright © 2018 Elsevier B.V. All rights reserved.

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

    Science.gov (United States)

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

    2014-08-01

    Members of various algal lineages are known to be strong producers of atmospherically relevant halogen emissions, that is a consequence of their capability to store and metabolize halogens. This study uses a noninvasive, synchrotron-based technique, X-ray absorption spectroscopy, for addressing in vivo bromine speciation in the brown algae Ectocarpus siliculosus, Ascophyllum nodosum, and Fucus serratus, the red algae Gracilaria dura, G. gracilis, Chondrus crispus, Osmundea pinnatifida, Asparagopsis armata, Polysiphonia elongata, and Corallina officinalis, the diatom Thalassiosira rotula, the dinoflagellate Lingulodinium polyedrum and a natural phytoplankton sample. The results highlight a diversity of fundamentally different bromine storage modes: while most of the stramenopile representatives and the dinoflagellate store mostly bromide, there is evidence for Br incorporated in nonaromatic hydrocarbons in Thalassiosira. Red algae operate various organic bromine stores - including a possible precursor (by the haloform reaction) for bromoform in Asparagopsis and aromatically bound Br in Polysiphonia and Corallina. Large fractions of the bromine in the red algae G. dura and C. crispus and the brown alga F. serratus are present as Br(-) defects in solid KCl, similar to what was reported earlier for Laminaria parts. These results are discussed according to different defensive strategies that are used within algal taxa to cope with biotic or abiotic stresses. © 2014 Phycological Society of America.

  1. Photophysiology and cellular composition of sea ice algae

    International Nuclear Information System (INIS)

    Lizotte, M.P.

    1989-01-01

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

  2. Dereplication and chemotaxonomical studies of marine algae of the Ochrophyta and Rhodophyta phyla.

    Science.gov (United States)

    Brkljača, Robert; Gӧker, Emrehan Semih; Urban, Sylvia

    2015-04-30

    Dereplication and chemotaxonomic studies of six marine algae of the Ochrophyta and one of the Rhodophyta phyla resulted in the detection of 22 separate compounds. All 16 secondary metabolites, including four new compounds (16-19), could be rapidly dereplicated using HPLC-NMR and HPLC-MS methodologies in conjunction with the MarinLit database. This study highlights the advantages of using NMR data (acquired via HPLC-NMR) for database searching and for the overall dereplication of natural products.

  3. Natural products from marine algae of the genus Osmundaria (Rhodophyceae, Ceramiales).

    Science.gov (United States)

    Osako, Kelvin; Teixeira, Valéria Laneuville

    2013-04-01

    The present work is a review of the natural products isolated from red marine algae of the genus Osmundaria (including Vidalia), which intends to encompass their occurrence in the species of this genus, the possible synonymies, their geographic distribution, their structural variety and their biological potential as prototypes for the pharmaceutical industry and as active principles of cosmetics. At the end, we provide a table with these natural products and their biological activities.

  4. Viruses of eukaryotic green algae. Final technical report, June 1, 1989--February 1, 1992

    Energy Technology Data Exchange (ETDEWEB)

    Van Etten, J.L.

    1992-12-31

    We have isolated and partially characterized many large, polyhedral, DNA containing, plaque forming viruses which infect certain unicellular, eukaryotic, chlorella-like green algae. These viruses have several unique features, including the fact that they code for DNA site-specific endonucleases and DNA methyltransferases. The primary objectives of this study were to identify, clone, and characterize some of the virus-encoded DNA methyltransferases and DNA restriction endonucleases in order to understand their biological function.

  5. [New additions to the marine algae of Mochima National Park, Sucre, Venezuela].

    Science.gov (United States)

    Silva, Soraida; Brito, Leonor; Lemus, Andrés

    2003-06-01

    The marine algal flora from the eastern coast of Mochima National Park, Sucre, Venezuela was studied with a total of 51 taxa identified, including eight new additions of red algae which are Erythrotrichia carnea (Dillwyn) J. Agardh, Sahlingia subintegra (Rosenvinge) Kornmann, Liagora ceranoides Lamouroux, Asparagopsis taxiformis (Delile) Trevisan, Dasya corymbifera J. Agardh, Chondria dasyphylla (Woodward) C. Agardh, Herposiphonia secunda f. tenella (C. Agardh) M.J. Wynne and Polysiphonia subtilissima Montagne. Morphological and anatomical aspects of the specimens are described and illustrated.

  6. Bromophycoic acids: bioactive natural products from a Fijian red alga Callophycus sp.

    Science.gov (United States)

    Teasdale, Margaret E; Shearer, Tonya L; Engel, Sebastian; Alexander, Troy S; Fairchild, Craig R; Prudhomme, Jacques; Torres, Manuel; Le Roch, Karine; Aalbersberg, William; Hay, Mark E; Kubanek, Julia

    2012-09-21

    Bioassay-guided fractionation of extracts from a Fijian red alga in the genus Callophycus resulted in the isolation of five new compounds of the diterpene-benzoate class. Bromophycoic acids A-E (1-5) were characterized by NMR and mass spectroscopic analyses and represent two novel carbon skeletons, one with an unusual proposed biosynthesis. These compounds display a range of activities against human tumor cell lines, malarial parasites, and bacterial pathogens including low micromolar suppression of MRSA and VREF.

  7. Synthesis and Characterization of Arsenolipids: Naturally Occurring Arsenic Compounds in Fish and Algae

    OpenAIRE

    Taleshi, Mojtaba S.; Seidler-Egdal, Rune K.; Jensen, Kenneth B.; Schwerdtle, Tanja; Francesconi, Kevin A.

    2014-01-01

    Arsenic-containing lipids (arsenolipids) are natural products present in fish and algae. Because these compounds occur in foods, there is considerable interest in their human toxicology. We report the synthesis and characterization of seven arsenic-containing lipids, including six natural products. The compounds comprise dimethylarsinyl groups attached to saturated long-chain hydrocarbons (three compounds), saturated long-chain fatty acids (two compounds), and monounsaturated long chain fatty...

  8. Uptake of technetium by marine algae: autoradiographic localization

    Energy Technology Data Exchange (ETDEWEB)

    Bonotto, S.; Nuyts, G.; Robbrecht, V.; Cogneau, M.; Ben, D. van der

    1988-02-01

    The uptake of technetium (sup(95m)Tc) by marine algae was localized by autoradiography. In the brown (Ascophyllum nodosum, Fucus spiralis and F. vesiculosus) as well as in the red (Porphyra umbilicalis) species, the distribution of technetium was heterogeneous, this radioelement being mostly accumulated in the parts of the plant which bear reproductive cells or which contain young tissues. Since brown algae have high concentration factors, they could constitute an important link in the transfer of technetium through the food chain. On the contrary, the edible alga Porphyra umbilicalis shows a very low incorporation of technetium.

  9. Dinitrogen fixation by blue-green algae from paddy fields

    International Nuclear Information System (INIS)

    Thomas, Joseph

    1977-01-01

    Recent work using radioactive nitrogen on the blue-green algae of paddy fields has been reviewed. These algae fix dinitrogen and photoassimilate carbon evolving oxygen, thereby augmenting nitrogen and carbon status of the soil and also providing oxygen to the water-logged rice paddies. Further studies using radioactive isotopes 13 N, 24 Na and 22 Na on their nitrogen fixation, nitrogen assimilation pathways; regulation of nitrogenase, heterocysts production and sporulation and sodium transport and metabolism have been carried out and reported. The field application of blue green algae for N 2 fixation was found to increase the status of soil nitrogen and yield of paddy. (M.G.B.)

  10. The biotechnological ways of blue-green algae complex processing

    OpenAIRE

    Nykyforov, Volodymyr; Malovanyy, Myroslav; Kozlovskaya, Tatyana; Novokhatko, Olha; Digtiar, Sergii

    2016-01-01

    The results of long­term research of various ways and methods of collection and processing of blue­green algae that cause “bloom” of the Dnieper reservoirs were presented. The possibility and feasibility of the blue­green algae biomass processing to biogas by methanogenesis were substantiated. It was found experimentally that preliminary mechanical cavitation of the blue­green algae biomass increases the biogas yield by 21.5 %. It was determined that the biogas produced contains up to 72 % of...

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

    Science.gov (United States)

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

    1995-01-01

    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.

  12. DNA barcoding of a new record of epi-endophytic green algae ...

    Indian Academy of Sciences (India)

    Epi-endophytic green algae comprise one of the most diverse and phylogenetically primitive groups of green algae and are considered to be ubiquitous in the world's oceans; however, no reports of these algae exist from India. Here we report the serendipitous discovery of Ulvella growing on intertidal green algae ...

  13. The toxicity of plastic nanoparticles to green algae as influenced by surface modification, medium hardness and cellular adsorption

    DEFF Research Database (Denmark)

    Nolte, Tom M.; Hartmann, Nanna B.; Kleijn, J. Mieke

    2017-01-01

    To investigate processes possibly underlying accumulation and ecological effects of plastic nano-particles we have characterized their interaction with the cell wall of green algae. More specifically, we have investigated the influence of particle surface functionality and water hardness (Ca2...... of nanoparticle bio-adsorption for green algae. The results show that the toxicity of nanoparticles can be better described and assessed by using appropriate dose metrics including material properties, complexation/agglomeration behavior and cellular attachment and adsorption. The applied methodology provides......+ concentration) on particle adsorption to algae cell walls. Polystyrene nanoparticles with different functional groups (non-functionalized, −COOH and −NH2) as well as coated (starch and PEG) gold nanoparticles were applied in these studies. Depletion measurements and atomic force microscopy (AFM) showed...

  14. Drift algae, an invasive snail and elevated temperature reduce ecological performance of a warm-temperate seagrass, through additive effects

    DEFF Research Database (Denmark)

    Hoffle, H.; Wernberg, T.; Thomsen, M. S.

    2012-01-01

    Seagrasses are under pressure from multiple concurrent threats, including rising temperatures, invasive species and nutrient-driven algal accumulations. We quantified the abundance of drift algae and the invasive snail Batillaria australis in 3 Halophila ovalis seagrass beds in the Swan River....... The survey showed that drift algae varied considerably between sites and sampling times, and sites experienced average loads of 0.4 to 0.8 kg fresh wt m(-2) and extreme loads up to 2.5 kg fresh wt m(-2). In contrast, invasive snails were constantly abundant at all sites at all collection times (mean......, suggesting increased risk of hypoxia. Invasive snails reduced the biomass of H. ovalis leaves and roots, increased leaf plastochrone interval and decreased the depth of the sulphide horizon. Finally, elevated temperature increased leaf loss and reduced leaf biomass, and, in the presence of drift algae, also...

  15. Sterol composition of the Adriatic Sea algae Ulva lactuca, Codium dichotomum, Cystoseira adriatica and Fucus virsoides

    Directory of Open Access Journals (Sweden)

    RADOMIR KAPETANOVIC

    2005-12-01

    Full Text Available The sterol composition of two green algae and two brown algae from the South Adriatic was determined. In the green alga Ulva lactuca, the principal sterols were cholesterol and isofucosterol. In the brown alga Cystoseira adriatica, the main sterols were cholesterol and stigmast-5-en-3ß-ol, while the characteristic sterol of the brown algae, fucosterol, was found only in low concentration. The sterol fractions of the green alga Codium dichotomum and the brown alga Fucus virsoides contained practically only one sterol each, comprising more than 90 % of the total sterols (clerosterol in the former and fucosterol in the latter.

  16. Potassium 4-(hydroxymethyl)-benzenosulfonate: a novel metabolite isolated from the marine red alga Bostrychia tenella (Rhodomelaceae, ceramiales); 4-(Hidroximetil)-Benzenossulfonato de potassio: metabolito inedito isolado da alga marinha Bostrychia tenella (Rhodomelaceae, ceramiales)

    Energy Technology Data Exchange (ETDEWEB)

    Felicio, Rafael de; Debonsi, Hosana Maria [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Ciencias Farmaceuticas. Dept. de Fisica e Quimica]. E-mail: hosana@fcfrp.usp.br; Yokoya, Nair Sumie [Instituto de Botanica de Sao Paulo, SP (Brazil). Secao de Ficologia

    2008-07-01

    Chemical investigation of the dichloromethane/methanol extract of the marine alga Bostrychia tenella has led to the isolation of two aromatic compounds, the new sulfate metabolite potassium 4-(hydroxymethyl)-benzenosulfonate (1) and the compound 1-methoxyphenethyl alcohol (2), described previously as a synthetic product. Their structures were determined by spectroscopic methods including NMR, MS, IR and by comparison with literature data. (author)

  17. Bicarbonate produced from carbon capture for algae culture.

    Science.gov (United States)

    Chi, Zhanyou; O'Fallon, James V; Chen, Shulin

    2011-11-01

    Using captured CO(2) to grow microalgae is limited by the high cost of CO(2) capture and transportation, as well as significant CO(2) loss during algae culture. Moreover, algae grow poorly at night, but CO(2) cannot be temporarily stored until sunrise. To address these challenges, we discuss a process where CO(2) is captured as bicarbonate and used as feedstock for algae culture, and the carbonate regenerated by the culture process is used as an absorbent to capture more CO(2). This process would significantly reduce carbon capture costs because it does not require additional energy for carbonate regeneration. Furthermore, not only would transport of the aqueous bicarbonate solution cost less than for that of compressed CO(2), but using bicarbonate would also provide a superior alternative for CO(2) delivery to an algae culture system. Copyright © 2011 Elsevier Ltd. All rights reserved.

  18. Extreme Low Light Requirement for Algae Growth Underneath Sea Ice

    DEFF Research Database (Denmark)

    Hancke, Kasper; Lund-Hansen, Lars C.; Lamare, Maxim L.

    2018-01-01

    Microalgae colonizing the underside of sea ice in spring are a key component of the Arctic foodweb as they drive early primary production and transport of carbon from the atmosphere to the ocean interior. Onset of the spring bloom of ice algae is typically limited by the availability of light......, and the current consensus is that a few tens-of-centimeters of snow is enough to prevent sufficient solar radiation to reach underneath the sea ice. We challenge this consensus, and investigated the onset and the light requirement of an ice algae spring bloom, and the importance of snow optical properties...... for light penetration. Colonization by ice algae began in May under >1 m of first-year sea ice with approximate to 1 m thick snow cover on top, in NE Greenland. The initial growth of ice algae began at extremely low irradiance (...

  19. Kalaärimeeste kohus algas venitamisega / Hindrek Riikoja

    Index Scriptorium Estoniae

    Riikoja, Hindrek

    2007-01-01

    Harju maakohtus algas kohtuprotsess veterinaar- ja toiduameti endise asejuhi Vladimir Razumovski väidetava altkäemaksuvõtmise üle, kus on süüdistavaid eraisikuid ja ettevõtjaid. Lisa: Kes on kohtu all?

  20. Ectocarpus: a model organism for the brown algae.

    Science.gov (United States)

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

    2012-02-01

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

  1. Potential pharmacological applications of polyphenolic derivatives from marine brown algae.

    Science.gov (United States)

    Thomas, Noel Vinay; Kim, Se-Kwon

    2011-11-01

    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. Copyright © 2011 Elsevier B.V. All rights reserved.

  2. Exploring the potential of using algae in cosmetics.

    Science.gov (United States)

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

    2015-05-01

    The applications of microalgae in cosmetic products have recently received more attention in the treatment of skin problems, such as aging, tanning and pigment disorders. There are also potential uses in the areas of anti-aging, skin-whitening, and pigmentation reduction products. While algae species have already been used in some cosmetic formulations, such as moisturizing and thickening agents, algae remain largely untapped as an asset in this industry due to an apparent lack of utility as a primary active ingredient. This review article focuses on integrating studies on algae pertinent to skin health and beauty, with the purpose of identifying serviceable algae functions in practical cosmetic uses. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Chemical examination of the Red alga Acanthophora spicifera

    Digital Repository Service at National Institute of Oceanography (India)

    Wahidullah, S.; Kamat, S.Y.

    Analyses of petroleum ether and chloroform extracts of the marine alga Acanthophora spicifera exhibiting antifertility activity led to the isolation of sterols and fatty acids as well as the rare dipeptides aurantiamides. All the compounds were...

  4. Chemical examination of the brown alga Stoechospermum marginatum (C. Agardh)

    Digital Repository Service at National Institute of Oceanography (India)

    Wahidullah, S.; DeSouza, L.; Kamat, S.Y.

    The crude methalonic extract of marine algae Stoechospermum marginatum from west coast of India was found to have spasmolytic activity. Search for the pharmacologically active compounds led to the isolation of steroids, fatty acids and an ester...

  5. The role of algae in agriculture: a mathematical study.

    Science.gov (United States)

    Tiwari, P K; Misra, A K; Venturino, Ezio

    2017-06-01

    Synthetic fertilizers and livestock manure are nowadays widely used in agriculture to improve crop yield but nitrogen and phosphorous runoff resulting from their use compromises water quality and contributes to eutrophication phenomena in waterbeds within the countryside and ultimately in the ocean. Alternatively, algae could play an important role in agriculture where they can be used as biofertilizers and soil stabilizers. To examine the possible reuse of the detritus generated by dead algae as fertilizer for crops, we develop three mathematical models building upon each other. A system is proposed in which algae recover waste nutrients (nitrogen and phosphorus) for reuse in agricultural production. The results of our study show that in so doing, the crop yield may be increased and simultaneously the density of algae in the lake may be reduced. This could be a way to mitigate and possibly solve the environmental and economic issues nowadays facing agriculture.

  6. Modelization of tritium transfer into the organic compartments of algae

    International Nuclear Information System (INIS)

    Bonotto, S.; Gerber, G.B.; Arapis, G.; Kirchmann, R.

    1982-01-01

    Uptake of tritium oxide and its conversion into organic tritium was studied in four different types of algae with widely varying size and growth characteristics (Acetabularia acetabulum, Boergesenia forbesii, two strains of Chlamydomonas and Dunaliella bioculata). Water in the cell and the vacuales equilibrates rapidly with external tritium water. Tritium is actively incorporated into organically bound form as the organisms grow. During the stationary phase, incorporation of tritium is slow. There exists a discrimination against the incorporation of tritium into organically bound form. A model has been elaborated taking in account these different factors. It appears that transfer of organic tritium by algae growing near the sites of release would be significant only for actively growing algae. Algae growing slowly may, however, be useful as cumulative indicators of discontinuous tritium release. (author)

  7. Scenario analysis of large scale algae production in tubular photobioreactors

    NARCIS (Netherlands)

    Slegers, P.M.; Beveren, van P.J.M.; Wijffels, R.H.; Straten, van G.; Boxtel, van A.J.B.

    2013-01-01

    Microalgae productivity in tubular photobioreactors depends on algae species, location, tube diameter, biomass concentration, distance between tubes and for vertically stacked systems, the number of horizontal tubes per stack. A simulation model for horizontal and vertically stacked horizontal

  8. Studies on allergenic algae of Delhi area: botanical aspects.

    Science.gov (United States)

    Mittal, A; Agarwal, M K; Shivpuri, D N

    1979-04-01

    To study distribution of algae in and around Delhi aerobiological surveys were undertaken for two consecutive years (September, 1972, to August, 1974). The surveys were accomplished by (a) slide exposure method and (b) culture plate exposure method. A total of 850 slides were exposed using Durham's gravity sampling device. Of these, 560 slides were exposed during 1973 (272 slides at two meter and 288 at ten meter height) and the rest (290 slides) were exposed during 1974 at ten meter height. A total of 858 culture plates were exposed (276 for one hour and 282 for two hours) during 1973 and the rest (300 culture plates) were exposed during 1974 at ten meter height for two hours duration only. Air was found to be rich in algae flora during the months of September to November. The dominant forms of algae present were all blue greens. This might be due to the relative greater resistance of blue green algae to unfavorable conditions.

  9. Lab on a chip technologies for algae detection: a review.

    Science.gov (United States)

    Schaap, Allison; Rohrlack, Thomas; Bellouard, Yves

    2012-08-01

    Over the last few decades, lab on a chip technologies have emerged as powerful tools for high-accuracy diagnosis with minute quantities of liquid and as tools for exploring cell properties in general. In this paper, we present a review of the current status of this technology in the context of algae detection and monitoring. We start with an overview of the detection methods currently used for algae monitoring, followed by a review of lab on a chip devices for algae detection and classification, and then discuss a case study based on our own research activities. We conclude with a discussion on future challenges and motivations for algae-oriented lab on a chip technologies. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Screening of complex fucoidans from four brown algae species as procoagulant agents.

    Science.gov (United States)

    Zhang, Zhenqing; Till, Susanne; Knappe, Sabine; Quinn, Catherine; Catarello, James; Ray, G Joseph; Scheiflinger, Friedrich; Szabo, Christina M; Dockal, Michael

    2015-01-22

    Fucoidans are complex sulfated polysaccharides extracted from brown algae. Depending on the concentration, they have been shown to stimulate and inhibit blood coagulation in vitro. Promotion of coagulation is mediated by blocking tissue factor pathway inhibitor (TFPI). We screened fucoidan extracts from four brown algae species in vitro with respect to their potential to improve coagulation in bleeding disorders. The fucoidans' pro- and anticoagulant activities were assessed by global hemostatic and standard clotting assays. Results showed that fucoidans improved coagulation parameters. Some fucoidans also activated the contact pathway of coagulation, an undesired property reported for sulfated glycosaminoglycans. Chemical evaluation of fucoidans' complex and variable structure included molecular weight (Mw), polydispersity (polyD), structural heterogeneity, and organic and inorganic impurities. Herewith, we describe a screening strategy that facilitates the identification of crude fucoidan extracts with desired biological and structural properties for improvement of compromised coagulation like in hemophilia. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Algae Drive Enhanced Darkening of Bare Ice on the Greenland Ice Sheet

    Science.gov (United States)

    Stibal, Marek; Box, Jason E.; Cameron, Karen A.; Langen, Peter L.; Yallop, Marian L.; Mottram, Ruth H.; Khan, Alia L.; Molotch, Noah P.; Chrismas, Nathan A. M.; Calı Quaglia, Filippo; Remias, Daniel; Smeets, C. J. P. Paul; van den Broeke, Michiel R.; Ryan, Jonathan C.; Hubbard, Alun; Tranter, Martyn; van As, Dirk; Ahlstrøm, Andreas P.

    2017-11-01

    Surface ablation of the Greenland ice sheet is amplified by surface darkening caused by light-absorbing impurities such as mineral dust, black carbon, and pigmented microbial cells. We present the first quantitative assessment of the microbial contribution to the ice sheet surface darkening, based on field measurements of surface reflectance and concentrations of light-absorbing impurities, including pigmented algae, during the 2014 melt season in the southwestern part of the ice sheet. The impact of algae on bare ice darkening in the study area was greater than that of nonalgal impurities and yielded a net albedo reduction of 0.038 ± 0.0035 for each algal population doubling. We argue that algal growth is a crucial control of bare ice darkening, and incorporating the algal darkening effect will improve mass balance and sea level projections of the Greenland ice sheet and ice masses elsewhere.

  12. Temperature-dependent toxicity of artemisinin toward the macrophyte Lemna minor and the algae Pseudokirchneriella subcapitata

    DEFF Research Database (Denmark)

    Jessing, Karina Knudsmark; Andresen, Marianne; Cedergreen, Nina

    2014-01-01

    - and groundwater. To make better risk assessments of A. annua which is cultivated under varying climatic conditions, the temperature-dependent toxicity of artemisinin toward the green algae Pseudokirchneriella subcapitata and the macrophyte Lemna minor was evaluated at temperatures ranging from 10 to 30°C....... To include a possible effect of temperature on the degradation rate of artemisinin, artemisinin concentrations were measured during the experiment and toxicity was related to the time-weighted averages of exposure concentrations. The toxicity of artemisinin toward the macrophyte L. minor and the algae P......Artemisinin, an antimalarial compound derivated from the cultivated plant Artemisia annua L., is produced in situ through cultivation of A. annua under different climatic conditions. The bioactive compound artemisinin has been observed to spread to the surroundings as well as to leach to surface...

  13. Wastewater use in algae production for generation of renewable resources: a review and preliminary results

    Science.gov (United States)

    2013-01-01

    Microalgae feedstock production can be integrated with wastewater and industrial sources of carbon dioxide. This study reviews the literature on algae grown on wastewater and includes a preliminary analysis of algal production based on anaerobic digestion sludge centrate from the Howard F. Curren Advanced Wastewater Treatment Plant (HFC AWTP) in Tampa, Florida and secondary effluent from the City of Lakeland wastewater treatment facilities in Lakeland, Florida. It was demonstrated that a mixed culture of wild algae species could successfully be grown on wastewater nutrients and potentially scaled to commercial production. Algae have demonstrated the ability to naturally colonize low-nutrient effluent water in a wetland treatment system utilized by the City of Lakeland. The results from these experiments show that the algae grown in high strength wastewater from the HFC AWTP are light-limited when cultivated indoor since more than 50% of the outdoor illumination is attenuated in the greenhouse. An analysis was performed to determine the mass of algae that can be supported by the wastewater nutrients (mainly nitrogen and phosphorous) available from the two Florida cities. The study was guided by the growth and productivity data obtained for algal growth in the photobioreactors in operation at the University of South Florida. In the analysis, nutrients and light are assumed to be limited, while CO2 is abundantly available. There is some limitation on land, especially since the HFC AWTP is located at the Port of Tampa. The temperature range in Tampa is assumed to be suitable for algal growth year round. Assuming that the numerous technical challenges to achieving commercial-scale algal production can be met, the results presented suggest that an excess of 71 metric tons per hectare per year of algal biomass can be produced. Two energy production options were considered; liquid biofuels from feedstock with high lipid content, and biogas generation from anaerobic

  14. Wastewater use in algae production for generation of renewable resources: a review and preliminary results.

    Science.gov (United States)

    Dalrymple, Omatoyo K; Halfhide, Trina; Udom, Innocent; Gilles, Benjamin; Wolan, John; Zhang, Qiong; Ergas, Sarina

    2013-01-05

    Microalgae feedstock production can be integrated with wastewater and industrial sources of carbon dioxide. This study reviews the literature on algae grown on wastewater and includes a preliminary analysis of algal production based on anaerobic digestion sludge centrate from the Howard F. Curren Advanced Wastewater Treatment Plant (HFC AWTP) in Tampa, Florida and secondary effluent from the City of Lakeland wastewater treatment facilities in Lakeland, Florida. It was demonstrated that a mixed culture of wild algae species could successfully be grown on wastewater nutrients and potentially scaled to commercial production. Algae have demonstrated the ability to naturally colonize low-nutrient effluent water in a wetland treatment system utilized by the City of Lakeland. The results from these experiments show that the algae grown in high strength wastewater from the HFC AWTP are light-limited when cultivated indoor since more than 50% of the outdoor illumination is attenuated in the greenhouse.An analysis was performed to determine the mass of algae that can be supported by the wastewater nutrients (mainly nitrogen and phosphorous) available from the two Florida cities. The study was guided by the growth and productivity data obtained for algal growth in the photobioreactors in operation at the University of South Florida. In the analysis, nutrients and light are assumed to be limited, while CO2 is abundantly available. There is some limitation on land, especially since the HFC AWTP is located at the Port of Tampa. The temperature range in Tampa is assumed to be suitable for algal growth year round. Assuming that the numerous technical challenges to achieving commercial-scale algal production can be met, the results presented suggest that an excess of 71 metric tons per hectare per year of algal biomass can be produced. Two energy production options were considered; liquid biofuels from feedstock with high lipid content, and biogas generation from anaerobic

  15. Diversity and ecology of filamentous green conjugate algae

    OpenAIRE

    Strouhalová, Pavla

    2016-01-01

    Filamentous conjugating algae have a cosmopolitan distribution. They often inhabit fragile freshwater habitats such as temporary hydrated ditches or puddles of melting snow. Occurrence in this environment entails having to deal with extreme conditions. That helps them to variously adaptation and also the formation of resistant stages. Algae belonging to this group have an important role in nature, because they are often the first species that inhabit newly created habitats and consequently al...

  16. Cytotoxicity of Algae Extracts on Normal and Malignant Cells

    OpenAIRE

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

    2011-01-01

    Algae preparations are commonly used in alternative medicine. We examined the effects of algae extracts on normal hematopoietic cells and leukemia cells. Ethanol extracts were prepared of Dunaliella salina (Dun), Astaxanthin (Ast), Spirulina platensis (Spir), and Aphanizomenon flos-aquae (AFA). Cell viability effects were completed by Annexin staining. Ast and AFA inhibited HL-60 and MV-4-11 whereas Dun and Spir had no effect. Primary AML blasts demonstrated increased apoptosis in AFA. ...

  17. Algae Reefs in Shark Bay, Western Australia, Australia

    Science.gov (United States)

    1990-01-01

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

  18. Using the marine unicellular algae in biological monitoring

    OpenAIRE

    Kapkov V. I.; Shoshina E. V.; Belenikina O. A.

    2017-01-01

    The possibility of using marine unicellular algae from natural plankton community in biomonitoring of pollution by heavy metals has been investigated. Algae of different taxa from the Mediterranean Sea have been allocated to culture. In the laboratory the culture conditions – i. e. growth medium, temperature, photoperiod, level of artificial light and initial density – have been selected for every species. The impact of heavy metals (Hg, Cd, Cu, Pb) in the form of chloride salts on the growth...

  19. The Non-Photosynthetic Algae Helicosporidium spp.: Emergence of a Novel Group of Insect Pathogens

    Directory of Open Access Journals (Sweden)

    Aurélien Tartar

    2013-07-01

    Full Text Available Since the original description of Helicosporidium parasiticum in 1921, members of the genus Helicosporidium have been reported to infect a wide variety of invertebrates, but their characterization has remained dependent on occasional reports of infection. Recently, several new Helicosporidium isolates have been successfully maintained in axenic cultures. The ability to produce large quantity of biological material has led to very significant advances in the understanding of Helicosporidium biology and its interactions with insect hosts. In particular, the unique infectious process has been well documented; the highly characteristic cyst and its included filamentous cell have been shown to play a central role during host infection and have been the focus of detailed morphological and developmental studies. In addition, phylogenetic analyses inferred from a multitude of molecular sequences have demonstrated that Helicosporidium are highly specialized non-photosynthetic algae (Chlorophyta: Trebouxiophyceae, and represent the first described entomopathogenic algae. This review provides an overview of (i the morphology of Helicosporidium cell types, (ii the Helicosporidium life cycle, including the entire infectious sequence and its impact on insect hosts, (iii the phylogenetic analyses that have prompted the taxonomic classification of Helicosporidium as green algae, and (iv the documented host range for this novel group of entomopathogens.

  20. The Non-Photosynthetic Algae Helicosporidium spp.: Emergence of a Novel Group of Insect Pathogens.

    Science.gov (United States)

    Tartar, Aurélien

    2013-07-17

    Since the original description of Helicosporidium parasiticum in 1921, members of the genus Helicosporidium have been reported to infect a wide variety of invertebrates, but their characterization has remained dependent on occasional reports of infection. Recently, several new Helicosporidium isolates have been successfully maintained in axenic cultures. The ability to produce large quantity of biological material has led to very significant advances in the understanding of Helicosporidium biology and its interactions with insect hosts. In particular, the unique infectious process has been well documented; the highly characteristic cyst and its included filamentous cell have been shown to play a central role during host infection and have been the focus of detailed morphological and developmental studies. In addition, phylogenetic analyses inferred from a multitude of molecular sequences have demonstrated that Helicosporidium are highly specialized non-photosynthetic algae (Chlorophyta: Trebouxiophyceae), and represent the first described entomopathogenic algae. This review provides an overview of (i) the morphology of Helicosporidium cell types, (ii) the Helicosporidium life cycle, including the entire infectious sequence and its impact on insect hosts, (iii) the phylogenetic analyses that have prompted the taxonomic classification of Helicosporidium as green algae, and (iv) the documented host range for this novel group of entomopathogens.

  1. The TOR Signaling Network in the Model Unicellular Green Alga Chlamydomonas reinhardtii

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    María Esther Pérez-Pérez

    2017-07-01

    Full Text Available Cell growth is tightly coupled to nutrient availability. The target of rapamycin (TOR kinase transmits nutritional and environmental cues to the cellular growth machinery. TOR functions in two distinct multiprotein complexes, termed TOR complex 1 (TORC1 and TOR complex 2 (TORC2. While the structure and functions of TORC1 are highly conserved in all eukaryotes, including algae and plants, TORC2 core proteins seem to be missing in photosynthetic organisms. TORC1 controls cell growth by promoting anabolic processes, including protein synthesis and ribosome biogenesis, and inhibiting catabolic processes such as autophagy. Recent studies identified rapamycin-sensitive TORC1 signaling regulating cell growth, autophagy, lipid metabolism, and central metabolic pathways in the model unicellular green alga Chlamydomonas reinhardtii. The central role that microalgae play in global biomass production, together with the high biotechnological potential of these organisms in biofuel production, has drawn attention to the study of proteins that regulate cell growth such as the TOR kinase. In this review we discuss the recent progress on TOR signaling in algae.

  2. The TOR Signaling Network in the Model Unicellular Green Alga Chlamydomonas reinhardtii.

    Science.gov (United States)

    Pérez-Pérez, María Esther; Couso, Inmaculada; Crespo, José L

    2017-07-12

    Cell growth is tightly coupled to nutrient availability. The target of rapamycin (TOR) kinase transmits nutritional and environmental cues to the cellular growth machinery. TOR functions in two distinct multiprotein complexes, termed TOR complex 1 (TORC1) and TOR complex 2 (TORC2). While the structure and functions of TORC1 are highly conserved in all eukaryotes, including algae and plants, TORC2 core proteins seem to be missing in photosynthetic organisms. TORC1 controls cell growth by promoting anabolic processes, including protein synthesis and ribosome biogenesis, and inhibiting catabolic processes such as autophagy. Recent studies identified rapamycin-sensitive TORC1 signaling regulating cell growth, autophagy, lipid metabolism, and central metabolic pathways in the model unicellular green alga Chlamydomonas reinhardtii . The central role that microalgae play in global biomass production, together with the high biotechnological potential of these organisms in biofuel production, has drawn attention to the study of proteins that regulate cell growth such as the TOR kinase. In this review we discuss the recent progress on TOR signaling in algae.

  3. Biodiesel Production From Algae to Overcome the Energy Crisis

    Directory of Open Access Journals (Sweden)

    Suliman Khan

    2017-10-01

    Full Text Available The use of energy sources has reached at the level that whole world is relying on it. Being the major source of energy, fuels are considered the most important. The fear of diminishing the available sources thirst towards biofuel production has increased during last decades. Considering the food problems, algae gain the most attention to be used as biofuel producers. The use of crop and food-producing plants will never be a best fit into the priorities for biofuel production as they will disturb the food needs. Different types of algae having the different production abilities. Normally algae have 20%–80% oil contents that could be converted into different types of fuels such as kerosene oil and biodiesel. The diesel production from algae is economical and easy. Different species such as tribonema, ulothrix and euglena have good potential for biodiesel production. Gene technology can be used to enhance the production of oil and biodiesel contents and stability of algae. By increasing the genetic expressions, we can find the ways to achieve the required biofuel amounts easily and continuously to overcome the fuels deficiency. The present review article focusses on the role of algae as a possible substitute for fossil fuel as an ideal biofuel reactant.

  4. Radionuclides and trace metals in eastern Mediterranean Sea algae

    Energy Technology Data Exchange (ETDEWEB)

    Al-Masri, M.S. E-mail: msmasri@aec.org.sy; Mamish, S.; Budier, Y

    2003-07-01

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

  5. Micro-algae: French players discuss the matter

    International Nuclear Information System (INIS)

    Bouveret, T.

    2013-01-01

    About 75000 species of algae have been reported so far, the domains of application are huge and investment are increasing all around the world. One of the difficulties is to find the most appropriate algae to a specific application. Some development programs have failed scientifically or economically for instance the production of protein for animal food from the chlorella algae or the production of bio-fuel from C14-C18 chains, from zeaxanthine and from phycoerytrine. On the other side some research programs have led to promising industrial applications such as the production of food for fish and farm animals. Some research fields are completely innovative such as the use of micro-algae for the construction of bio-walls for buildings. Micro-algae are diverse and fragile. Photo-bioreactors have been designed to breed fragile algae like some types of chlorophycees used in bio-fuel and in cosmetics, a prototype has been tested for 15 months and its production is about 2 kg of dry matter a day. (A.C.)

  6. Biofuels and algae; Biocarburants, la promesse des algues

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2011-07-15

    Bio-fuels based on micro-algae are promising, their licensing for being used in plane fuels in a mix containing 50% of fossil kerosene is expected in the coming months. In United-States research on bio-fuels has been made more important since 2006 when 2 policies were launched: 'Advanced energy initiative' and 'Twenty-in-ten', the latter aiming to develop alternative fuels. In Europe less investment has been made concerning micro-algae fuels but research programs were launched in Spain, United-Kingdom and France. In France 3 important projects were launched: SHAMASH (2006-2010) whose aim is to produce lipidic fuels from micro-algae, ALGOHUB (2008-2013) whose aim is to use micro-algae as a raw material for humane and animal food, medicine and cosmetics, SYMBIOSE (2009-2011) whose aim is the optimization of the production of methane through the anaerobic digestion of micro-algae, SALINALGUE (2010-2016) whose aim is to grow micro-algae for the production of bio-energies and bio-products. (A.C.)

  7. Radionuclides and trace metals in eastern Mediterranean Sea algae

    International Nuclear Information System (INIS)

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

    2003-01-01

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

  8. Integrating Algae with Bioenergy Carbon Capture and Storage (ABECCS) Increases Sustainability

    Science.gov (United States)

    Beal, Colin M.; Archibald, Ian; Huntley, Mark E.; Greene, Charles H.; Johnson, Zackary I.

    2018-03-01

    Bioenergy carbon capture and storage (BECCS) has been proposed to reduce atmospheric CO2 concentrations, but concerns remain about competition for arable land and freshwater. The synergistic integration of algae production, which does not require arable land or freshwater, with BECCS (called "ABECCS") can reduce CO2 emissions without competing with agriculture. This study presents a technoeconomic and life-cycle assessment for colocating a 121-ha algae facility with a 2,680-ha eucalyptus forest for BECCS. The eucalyptus biomass fuels combined heat and power (CHP) generation with subsequent amine-based carbon capture and storage (CCS). A portion of the captured CO2 is used for growing algae and the remainder is sequestered. Biomass combustion supplies CO2, heat, and electricity, thus increasing the range of sites suitable for algae cultivation. Economic, energetic, and environmental impacts are considered. The system yields as much protein as soybeans while generating 61.5 TJ of electricity and sequestering 29,600 t of CO2 per year. More energy is generated than consumed and the freshwater footprint is roughly equal to that for soybeans. Financial break-even is achieved for product value combinations that include 1) algal biomass sold for 1,400/t (fishmeal replacement) with a 68/t carbon credit and 2) algal biomass sold for 600/t (soymeal replacement) with a 278/t carbon credit. Sensitivity analysis shows significant reductions to the cost of carbon sequestration are possible. The ABECCS system represents a unique technology for negative emissions without reducing protein production or increasing water demand, and should therefore be included in the suite of technologies being considered to address global sustainability.

  9. Is the tier-1 effect assessment for herbicides protective for aquatic algae and vascular plant communities?

    Science.gov (United States)

    van Wijngaarden, René P A; Arts, Gertie H P

    2018-01-01

    In the aquatic tier-1 effect assessment for plant protection products with an herbicidal mode of action in Europe, it is usually algae and/or vascular plants that determine the environmental risks. This tier includes tests with at least 2 algae and 1 macrophyte (Lemna). Although such tests are considered to be of a chronic nature (based on the duration of the test in relation to the life cycle of the organism), the measurement endpoints derived from the laboratory tests with plants (including algae) and used in the first-tier effect assessment for herbicides are acute effect concentrations affecting 50% of the test organisms (EC50 values) and not no-observed-effect concentrations (NOECs) or effect concentrations affecting 10% of the test organisms (EC10) values. Other European legislative frameworks (e.g., the Water Framework Directive) use EC10 values. The present study contributes to a validation of the tiered herbicide risk assessment approach by comparing the standard first-tier effect assessment with results of microcosm and mesocosm studies. We evaluated EC50 and EC10 values for standard test algae and macrophytes based on either the growth rate endpoint (E r C50) or the lowest available endpoint for growth rate or biomass/yield (E r /E y C50). These values were compared with the regulatory acceptable concentrations for the threshold option as derived from microcosm and mesocosm studies. For these studies, protection is maintained if growth rate is taken as the regulatory endpoint instead of the lowest value of either growth rate or biomass/yield in conjunction with the standard assessment factor of 10. Based on a limited data set of 14 herbicides, we did not identify a need to change the current practice. Environ Toxicol Chem 2018;37:175-183. © 2017 SETAC. © 2017 SETAC.

  10. Photoprotection strategies of the alga Nannochloropsis gaditana.

    Science.gov (United States)

    Chukhutsina, Volha U; Fristedt, Rikard; Morosinotto, Tomas; Croce, Roberta

    2017-07-01

    Nannochloropsis spp. are algae with high potential for biotechnological applications due to their capacity to accumulate lipids. However, little is known about their photosynthetic apparatus and acclimation/photoprotective strategies. In this work, we studied the mechanisms of non-photochemical quenching (NPQ), the fast response to high light stress, in Nannochloropsis gaditana by "locking" the cells in six different states during quenching activation and relaxation. Combining biochemical analysis with time-resolved fluorescence spectroscopy, we correlated each NPQ state with the presence of two well-known NPQ components: de-epoxidized xanthophylls and stress-related antenna proteins (LHCXs). We demonstrated that after exposure to strong light, the rapid quenching that takes place in the antennas of both photosystems was associated with the presence of LHCXs. At later stages, quenching occurs mainly in the antennas of PSII and correlates with the amount of de-epoxidised xanthophylls. We also observed changes in the distribution of excitation energy between photosystems, which suggests redistribution of excitation between photosystems as part of the photo-protective strategy. A multistep model for NPQ induction and relaxation in N. gaditana is discussed. Copyright © 2017. Published by Elsevier B.V.

  11. Is the Future Really in Algae?

    Science.gov (United States)

    Trent, Jonathan

    2011-01-01

    Having just emerged from the warmest decade on record and watching as the oceans acidify, global resources peak, the world's population continues to climb, and nearly half of all known species face extinction by the end of the century. We stand on the threshold of one of the most important transition in human history-the transition from hunting-and-gathering our energy to cultivating sustainable, carbon-neutral, environmentally-friendly energy supplies. Can we "cultivate" enerm without competing with agriculture for land, freshwater, or fertilizer? Can we develop an "ecology of technology" that optimizes our use of limited resources? Is human activity compatible with improved conditions in the world's oceans? Will our ingenuity prevail in time to make a difference for our children and the children of all species? With support from NASA ARMD and the California Energy Commission, a group of dedicated scientists and engineers are working on a project called OMEGA (Offshore Membrane Enclosures for Growing Algae), to provide practical answers to these critical questions and to leave a legacy of hope for the oceans and for the future.

  12. Detection of Cyanotoxins in Algae Dietary Supplements

    Directory of Open Access Journals (Sweden)

    Audrey Roy-Lachapelle

    2017-02-01

    Full Text Available Algae dietary supplements are marketed worldwide as natural health products. Although their proprieties have been claimed as beneficial to improve overall health, there have been several previous reports of contamination by cyanotoxins. These products generally contain non-toxic cyanobacteria, but the methods of cultivation in natural waters without appropriate quality controls allow contamination by toxin producer species present in the natural environment. In this study, we investigated the presence of total microcystins, seven individual microcystins (RR, YR, LR, LA, LY, LW, LF, anatoxin-a, dihydroanatoxin-a, epoxyanatoxin-a, cylindrospermopsin, saxitoxin, and β-methylamino-l-alanine in 18 different commercially available products containing Spirulina or Aphanizomenon flos-aquae. Total microcystins analysis was accomplished using a Lemieux oxidation and a chemical derivatization using dansyl chloride was needed for the simultaneous analysis of cylindrospermopsin, saxitoxin, and β-methylamino-l-alanine. Moreover, the use of laser diode thermal desorption (LDTD and ultra-high performance liquid chromatography (UHPLC both coupled to high resolution mass spectrometry (HRMS enabled high performance detection and quantitation. Out of the 18 products analyzed, 8 contained some cyanotoxins at levels exceeding the tolerable daily intake values. The presence of cyanotoxins in these algal dietary supplements reinforces the need for a better quality control as well as consumer’s awareness on the potential risks associated with the consumption of these supplements.

  13. The toxicity of plastic nanoparticles to green algae as influenced by surface modification, medium hardness and cellular adsorption

    Energy Technology Data Exchange (ETDEWEB)

    Nolte, Tom M., E-mail: T.Nolte@science.ru.nl [Department of Environmental Engineering, Technical University of Denmark, Miljøvej, B113, 2800 Kgs. Lyngby (Denmark); Radboud University Nijmegen, Institute for Water and Wetland Research, Department of Environmental Science, P.O. Box 9010, NL-6500 GL, Nijmegen (Netherlands); Hartmann, Nanna B. [Department of Environmental Engineering, Technical University of Denmark, Miljøvej, B113, 2800 Kgs. Lyngby (Denmark); Kleijn, J. Mieke [Physical Chemistry Soft Matter, Wageningen University, Stippeneng 4, NL-6708WE Wageningen (Netherlands); Garnæs, Jørgen [Danish Fundamental Metrology, Matematiktorvet 307, 2800 Kgs. Lyngby (Denmark); Meent, Dik van de [Radboud University Nijmegen, Institute for Water and Wetland Research, Department of Environmental Science, P.O. Box 9010, NL-6500 GL, Nijmegen (Netherlands); National Institute of Public Health and the Environment RIVM, P.O. Box 1, 3720 BA, Bilthoven (Netherlands); Jan Hendriks, A. [Radboud University Nijmegen, Institute for Water and Wetland Research, Department of Environmental Science, P.O. Box 9010, NL-6500 GL, Nijmegen (Netherlands); Baun, Anders [Department of Environmental Engineering, Technical University of Denmark, Miljøvej, B113, 2800 Kgs. Lyngby (Denmark)

    2017-02-15

    Highlights: • P. subcapitata cultures were exposed to plastic nanoparticles in adsorption assays. • UV/Vis and AFM showed ionic strength and surface chemistry influence adsorption of anionic and neutral nanoplastics. • Growth inhibition of algae is antagonistically influenced by carboxylate-modified polystyrene and calcium. • Physico-chemical characterization and proper dose metrics can be used to predict ecotoxicity. - Abstract: To investigate processes possibly underlying accumulation and ecological effects of plastic nano-particles we have characterized their interaction with the cell wall of green algae. More specifically, we have investigated the influence of particle surface functionality and water hardness (Ca{sup 2+} concentration) on particle adsorption to algae cell walls. Polystyrene nanoparticles with different functional groups (non-functionalized, −COOH and −NH{sub 2}) as well as coated (starch and PEG) gold nanoparticles were applied in these studies. Depletion measurements and atomic force microscopy (AFM) showed that adsorption of neutral and positively charged plastic nanoparticles onto the cell wall of P. subcapitata was stronger than that of negatively charged plastic particles. Results indicated that binding affinity is a function of both inter-particle and particle-cell wall interactions which are in turn influenced by the medium hardness and particle concentration. Physicochemical modelling using DLVO theory was used to interpret the experimental data, using also values for interfacial surface free energies. Our study shows that material properties and medium conditions play a crucial role in the rate and state of nanoparticle bio-adsorption for green algae. The results show that the toxicity of nanoparticles can be better described and assessed by using appropriate dose metrics including material properties, complexation/agglomeration behavior and cellular attachment and adsorption. The applied methodology provides an efficient

  14. Lipid oxidation in base algae oil and water-in-algae oil emulsion: Impact of natural antioxidants and emulsifiers.

    Science.gov (United States)

    Chen, Bingcan; Rao, Jiajia; Ding, Yangping; McClements, David Julian; Decker, Eric Andrew

    2016-07-01

    The impact of natural hydrophilic antioxidants, metal chelators, and hydrophilic antioxidant/metal chelator mixture on the oxidative stability of base algae oil and water-in-algae oil emulsion was investigated. The results showed that green tea extract and ascorbic acid had greatest protective effect against algae oil oxidation and generated four day lag phase, whereas rosmarinic acid, grape seed extract, grape seed extract polymer, deferoxamine (DFO), and ethylenediaminetetraacetic acid (EDTA) had no significant protective effect. Besides, there was no synergistic effect observed between natural antioxidants and ascorbic acid. The emulsifiers are critical to the physicochemical stability of water-in-algae oil emulsions. Polyglycerol polyricinoleate (PGPR) promoted the oxidation of emulsion. Conversely, the protective effect on algae oil oxidation was appreciated when defatted soybean lecithin (PC 75) or defatted lyso-lecithin (Lyso-PC) was added. The role of hydrophilic antioxidants in emulsion was similar to that in algae oil except EDTA which demonstrated strong antioxidative effect in emulsion. The results could provide information to build up stable food products containing polyunsaturated fatty acids (PUFA). Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. SOIL ALGAE OF BLADE OF COIL IN DONETSK REGION

    Directory of Open Access Journals (Sweden)

    Maltseva I.A.

    2011-12-01

    Full Text Available On territory of Donbass for more than 200 years the underground coal mining has produced, accompanied by the formation of the mine dumps. Finding ways to reduce their negative impact on the environment should be based on their comprehensive study. The soil algae are active participants in the syngenetic processes in industrial dumps of different origin. The purpose of this paper is to identify the species composition and dominant algae groups in dump mine SH/U5 “Western” in the western part of Donetsk.The test blade is covered with vegetation to the middle from all sides, and on the north side of 20-25 m to the top. The vegetation cover of the lower and middle tiers of all the exposures range in 70-80%. Projective vegetation cover of upper tiers of the northern, north-eastern and north-western exposures are in the range of 20-40%, other – 5-10%. We revealed some 38 algae species as a result of our research in southern, northern, western, and eastern slopes of the blade “Western”. The highest species diversity has Chlorophyta - 14 species (36.8% of the total number of species, then Cyanophyta - 9 (23,7%, Bacillariophyta - 7 (18,4%, Xantophyta - 5 (13.2%, and Eustigmatophyta - 3 (7.9%. The dominants are represented by Hantzschia amphyoxys (Ehrenberg Grunow in Cleve et Grunow, Bracteacoccus aerius, Klebsormidium flaccidum (Kützing Silva et al., Phormidium autumnale, Pinnularia borealis Ehrenberg, Planothidium lanceolatum (Brebisson in Kützing Bukhtiyarova, Xanthonema exile (Klebs Silva.It should be noted that the species composition of algae groups in different slopes of the blade was significantly different. Jacquard coefficient was calculated for algae communities varied in the range of 15,4-39,1%. The smallest number of algae species was observed on the southern slope of the blade (14 species, maximum was registered in the areas of north and west slopes. Differences in the species composition of algae were also observed in three

  16. The effects of preparing methods and enzyme supplementation on the utilization of brown marine algae (Sargassum dentifebium meal in the diet of laying hens

    Directory of Open Access Journals (Sweden)

    Mohammed A. Al-Harthi

    2011-10-01

    Full Text Available Brown marine algae (BMA; Sargassum dentifebium were collected from Jeddah on the shores of the Red Sea and sun dried at an average daily temperature of 40°C until constant weight was obtained. Part of the sun dried brown marine algae was subsequently processed by boiling (BBMA;boiled brown marine algae in water and by autoclaving (ABMA; autoclaved brown marine algae. The SBMA, BBMA and ABMA were included in laying hen diet during weeks 23-42 of age at concentrations of 0.0%, 3.0% and 6.0%. The diets were given with or without enzyme supplementation. This resulted in 3 (preparation methods × 2 (concentrations of supplemented BMA, i.e. 3 and 6 % × 2 (with and without enzyme supplementation diet programs plus two control groups (with and without enzyme supplementation for a total of 14 treatments. Each treatment was represented by six replicates of five hens each. Sun dried or autocalved brown marine algae at 3% without enzyme supplementation in the laying hen diet could be fed to laying hens without any adverse effect on laying performance. However, enzyme supplementation to a diet containing 6% autocalved brown marine algae improved productive performance and eggshell quality.

  17. Algae biodiesel life cycle assessment using current commercial data.

    Science.gov (United States)

    Passell, Howard; Dhaliwal, Harnoor; Reno, Marissa; Wu, Ben; Ben Amotz, Ami; Ivry, Etai; Gay, Marcus; Czartoski, Tom; Laurin, Lise; Ayer, Nathan

    2013-11-15

    Autotrophic microalgae represent a potential feedstock for transportation fuels, but life cycle assessment (LCA) studies based on laboratory-scale or theoretical data have shown mixed results. We attempt to bridge the gap between laboratory-scale and larger scale biodiesel production by using cultivation and harvesting data from a commercial algae producer with ∼1000 m(2) production area (the base case), and compare that with a hypothetical scaled up facility of 101,000 m(2) (the future case). Extraction and separation data are from Solution Recovery Services, Inc. Conversion and combustion data are from the Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation Model (GREET). The LCA boundaries are defined as "pond-to-wheels". Environmental impacts are quantified as NER (energy in/energy out), global warming potential, photochemical oxidation potential, water depletion, particulate matter, and total NOx and SOx. The functional unit is 1 MJ of energy produced in a passenger car. Results for the base case and the future case show an NER of 33.4 and 1.37, respectively and GWP of 2.9 and 0.18 kg CO2-equivalent, respectively. In comparison, petroleum diesel and soy diesel show an NER of 0.18 and 0.80, respectively and GWP of 0.12 and 0.025, respectively. A critical feature in this work is the low algal productivity (3 g/m(2)/day) reported by the commercial producer, relative to the much higher productivities (20-30 g/m(2)/day) reported by other sources. Notable results include a sensitivity analysis showing that algae with an oil yield of 0.75 kg oil/kg dry biomass in the future case can bring the NER down to 0.64, more comparable with petroleum diesel and soy biodiesel. An important assumption in this work is that all processes are fully co-located and that no transport of intermediate or final products from processing stage to stage is required. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. Morphological and community changes of turf algae in competition with corals

    Science.gov (United States)

    Cetz-Navarro, Neidy P.; Quan-Young, Lizette I.; Espinoza-Avalos, Julio

    2015-08-01

    The morphological plasticity and community responses of algae competing with corals have not been assessed. We evaluated eight morphological characters of four species of stoloniferous clonal filamentous turf algae (FTA), including Lophosiphonia cristata (Lc) and Polysiphonia scopulorum var. villum (Psv), and the composition and number of turf algae (TA) in competition for space with the coral Orbicella spp. under experimental and non-manipulated conditions. All FTA exhibited morphological responses, such as increasing the formation of new ramets (except for Psv when competing with O. faveolata). Opposite responses in the space between erect axes were found when Psv competed with O. faveolata and when Lc competed with O. annularis. The characters modified by each FTA species, and the number and composition of TA species growing next to coral tissue differed from that of the TA growing at ≥3 cm. The specific and community responses indicate that some species of TA can actively colonise coral tissue and that fundamental competitive interactions between the two types of organisms occur within the first millimetres of the coral-algal boundary. These findings suggest that the morphological plasticity, high number, and functional redundancy of stoloniferous TA species favour their colonisation of coral tissue and resistance against coral invasion.

  19. ETOILE regulates developmental patterning in the filamentous brown alga Ectocarpus siliculosus.

    Science.gov (United States)

    Le Bail, Aude; Billoud, Bernard; Le Panse, Sophie; Chenivesse, Sabine; Charrier, Bénédicte

    2011-04-01

    Brown algae are multicellular marine organisms evolutionarily distant from both metazoans and land plants. The molecular or cellular mechanisms that govern the developmental patterning in brown algae are poorly characterized. Here, we report the first morphogenetic mutant, étoile (etl), produced in the brown algal model Ectocarpus siliculosus. Genetic, cellular, and morphometric analyses showed that a single recessive locus, ETL, regulates cell differentiation: etl cells display thickening of the extracellular matrix (ECM), and the elongated, apical, and actively dividing E cells are underrepresented. As a result of this defect, the overrepresentation of round, branch-initiating R cells in the etl mutant leads to the rapid induction of the branching process at the expense of the uniaxial growth in the primary filament. Computational modeling allowed the simulation of the etl mutant phenotype by including a modified response to the neighborhood information in the division rules used to specify wild-type development. Microarray experiments supported the hypothesis of a defect in cell-cell communication, as primarily Lin-Notch-domain transmembrane proteins, which share similarities with metazoan Notch proteins involved in binary cell differentiation were repressed in etl. Thus, our study highlights the role of the ECM and of novel transmembrane proteins in cell-cell communication during the establishment of the developmental pattern in this brown alga.

  20. On reproduction in red algae: further research needed at the molecular level.

    Science.gov (United States)

    García-Jiménez, Pilar; Robaina, Rafael R

    2015-01-01

    Multicellular red algae (Rhodophyta) have some of the most complex life cycles known in living organisms. Economically valuable seaweeds, such as phycocolloid producers, have a triphasic (gametophyte, carposporophyte, and tetrasporophyte) life cycle, not to mention the intricate alternation of generations in the edible "sushi-alga" nori. It is a well-known fact that reproductive processes are controlled by one or more abiotic factor(s), including day length, light quality, temperature, and nutrients. Likewise, endogenous chemical factors such as plant growth regulators have been reported to affect reproductive events in some red seaweeds. Still, in the genomic era and given the high throughput techniques at our disposal, our knowledge about the endogenous molecular machinery lags far behind that of higher plants. Any potential effective control of the reproductive process will entail revisiting most of these results and facts to answer basic biological questions as yet unresolved. Recent results have shed light on the involvement of several genes in red alga reproductive events. In addition, a working species characterized by a simple filamentous architecture, easy cultivation, and accessible genomes may also facilitate our task.

  1. Toward systems biology in brown algae to explore acclimation and adaptation to the shore environment.

    Science.gov (United States)

    Tonon, Thierry; Eveillard, Damien; Prigent, Sylvain; Bourdon, Jérémie; Potin, Philippe; Boyen, Catherine; Siegel, Anne

    2011-12-01

    Brown algae belong to a phylogenetic lineage distantly related to land plants and animals. They are almost exclusively found in the intertidal zone, a harsh and frequently changing environment where organisms are submitted to marine and terrestrial constraints. In relation with their unique evolutionary history and their habitat, they feature several peculiarities, including at the level of their primary and secondary metabolism. The establishment of Ectocarpus siliculosus as a model organism for brown algae has represented a framework in which several omics techniques have been developed, in particular, to study the response of these organisms to abiotic stresses. With the recent publication of medium to high throughput profiling data, it is now possible to envision integrating observations at the cellular scale to apply systems biology approaches. As a first step, we propose a protocol focusing on integrating heterogeneous knowledge gained on brown algal metabolism. The resulting abstraction of the system will then help understanding how brown algae cope with changes in abiotic parameters within their unique habitat, and to decipher some of the mechanisms underlying their (1) acclimation and (2) adaptation, respectively consequences of (1) the behavior or (2) the topology of the system resulting from the integrative approach.

  2. RESOLVING EVOLUTIONARY RELATIONSHIPS AMONG THE BROWN ALGAE USING CHLOROPLAST AND NUCLEAR GENES(1).

    Science.gov (United States)

    Phillips, Naomi; Burrowes, Renaud; Rousseau, Florence; De Reviers, Bruno; Saunders, Gary W

    2008-04-01

    The brown algae are one of the largest and most important groups of primary producers in benthic coastal marine environments. Despite their biological importance, consensus regarding their taxonomic or evolutionary relationships remains elusive. Our goal was to produce a taxon-rich two-gene (rbcL and LSU rDNA) phylogeny. Key species were sequenced to represent each order and family in the analyses across all 19 orders and ∼40 families, including selected outgroups Schizocladiophyceae and Xanthophyceae. Our results are in sharp contrast to traditional phylogenetic concepts; the Ectocarpales are not an early diverging clade, nor do the Fucales diverge early from other brown algae. Rather, Choristocarpus is sister to the remaining brown algae. Other groups traditionally considered to have primitive features are actually recently diverged lineages, turning traditional phylogenetic concepts upside down. Additionally, our results allow for the assessment, in the broadest context, of many of the historical and more recent taxonomic changes, resulting in several emended groups along with proposals for two new orders (Onslowiales, Nemodermatales) and one new family (Phaeosiphoniellaceae). © 2008 Phycological Society of America.

  3. Cell death upon H(2)O(2) induction in the unicellular green alga Micrasterias.

    Science.gov (United States)

    Darehshouri, A; Affenzeller, M; Lütz-Meindl, U

    2008-11-01

    In the present study, we investigated whether the unicellular green alga Micrasterias denticulata is capable of executing programmed cell death (PCD) upon experimental induction, and which morphological, molecular and physiological hallmarks characterise this. This is particularly interesting as unicellular freshwater green algae growing in shallow bog ponds are exposed to extreme environmental conditions, and the capacity to perform PCD may be an important strategy to guarantee survival of the population. The theoretically 'immortal' alga Micrasterias is an ideal object for such investigations as it has served as a cell biological model system for many years and details on its growth properties, physiology and ultrastructure throughout the cell cycle are well known. Treatments with low concentrations of H(2)O(2) are known to induce PCD in other organisms, resulting in severe ultrastructural changes to organelles, as observed in TEM. These include deformation and part disintegration of mitochondria, abnormal dilatation of cisternal rims of dictyosomes, occurrence of multivesicular bodies, an increase in the number of ER compartments, and slight condensation of chromatin. Additionally, a statistically significant increase in caspase-3-like activity was detected, which was abrogated by a caspase-3 inhibitor. Photosynthetic activity measured by fast chlorophyll fluorescence decreased as a consequence of H(2)O(2) exposure, whereas pigment composition, except for a reduction in carotenoids, was the same as in untreated controls. TUNEL positive staining and ladder-like degradation of DNA, both frequently regarded as a hallmark of PCD in higher plants, could only be detected in dead Micrasterias cells.

  4. Evolution of Individuality: A Case Study in the Volvocine Green Algae

    Directory of Open Access Journals (Sweden)

    Erik R. Hanschen

    2017-01-01

    Full Text Available While numerous criteria have been proposed in definitions of biological individuality, it is not clear whether these criteria reflect the evolutionary processes that underlie transitions in individuality. We consider the evolution of individuality during the transition from unicellular to multicellular life. We assume that “individuality” (however it is defined has changed in the volvocine green algae lineage during the transition from single cells, to simple multicellular colonies with four to one hundred cells, to more complex multicellular organisms with thousands of differentiated cells. We map traits associated with the various proposed individuality criteria onto volvocine algae species thought to be similar to ancestral forms arising during this transition in individuality. We find that the fulfillment of some criteria, such as genetic homogeneity and genetic uniqueness, do not change across species, while traits underpinning other aspects of individuality, including degrees of integration, group-level fitness and adaptation, and group indivisibility, change dramatically. We observe that different kinds of individuals likely exist at different levels of organization (cell and group in the same species of algae. Future research should focus on the causes and consequences of variation in individuality.

  5. Genomic analysis of organismal complexity in the multicellular green alga Volvox carteri

    Energy Technology Data Exchange (ETDEWEB)

    Prochnik, Simon E.; Umen, James; Nedelcu, Aurora; Hallmann, Armin; Miller, Stephen M.; Nishii, Ichiro; Ferris, Patrick; Kuo, Alan; Mitros, Therese; Fritz-Laylin, Lillian K.; Hellsten, Uffe; Chapman, Jarrod; Simakov, Oleg; Rensing, Stefan A.; Terry, Astrid; Pangilinan, Jasmyn; Kapitonov, Vladimir; Jurka, Jerzy; Salamov, Asaf; Shapiro, Harris; Schmutz, Jeremy; Grimwood, Jane; Lindquist, Erika; Lucas, Susan; Grigoriev, Igor V.; Schmitt, Rudiger; Kirk, David; Rokhsar, Daniel S.

    2010-07-01

    Analysis of the Volvox carteri genome reveals that this green alga's increased organismal complexity and multicellularity are associated with modifications in protein families shared with its unicellular ancestor, and not with large-scale innovations in protein coding capacity. The multicellular green alga Volvox carteri and its morphologically diverse close relatives (the volvocine algae) are uniquely suited for investigating the evolution of multicellularity and development. We sequenced the 138 Mb genome of V. carteri and compared its {approx}14,500 predicted proteins to those of its unicellular relative, Chlamydomonas reinhardtii. Despite fundamental differences in organismal complexity and life history, the two species have similar protein-coding potentials, and few species-specific protein-coding gene predictions. Interestingly, volvocine algal-specific proteins are enriched in Volvox, including those associated with an expanded and highly compartmentalized extracellular matrix. Our analysis shows that increases in organismal complexity can be associated with modifications of lineage-specific proteins rather than large-scale invention of protein-coding capacity.

  6. Use of Spring-Coiled Shaped Green Algae for Determination of 137Cs and Potassium Bioaccumulation

    International Nuclear Information System (INIS)

    Gonen, R.; Katorza, E.; German, U.; Pelled, O.; Dody, A.; Marco, R.; Cohen, E.; Alfassi, Z.B.

    2006-01-01

    One of the useful technologies for removing pollutants from the environment is phyto remediation. By this method, living or dead plants (including various algae and cyanobacteria) are used to concentrate pollutants from soil or from water sources by biologically active or by passive processes. We isolated from one of the water pools in the Negev green filamentous algae. They exhibited a regular spring-coiled shape typical to Spirulina filaments, but lacked the beaded filaments seen in Anabaena which belongs also to the cyanobacteria. The easily growing algae at the high temperatures of the Negev summers (35-45 degrees C) and under extremely alkaline conditions (pH=9-11), were used to test their potential to accumulate radio-isotopes. We performed our investigations by using 137 Cs, which is a fission product and is regarded as an environmental contaminant. Cesium, Rubidium, Lithium and Sodium follow the uptake route of the macro nutrient potassium and appear to share the K + transport carrier, therefore they are easily transported into plant cells. Potassium is generally considered as an effective inhibitor for radio-cesium uptake by plant roots. It was also shown that C.a. and Mag depressed the Cs uptake). Bioaccumulation factors were used to predict radionuclide concentrations in whole organisms or their tissues

  7. Environmental behavior and ecotoxicity of engineered nanoparticles to algae, plants, and fungi.

    Science.gov (United States)

    Navarro, Enrique; Baun, Anders; Behra, Renata; Hartmann, Nanna B; Filser, Juliane; Miao, Ai-Jun; Quigg, Antonietta; Santschi, Peter H; Sigg, Laura

    2008-07-01

    Developments in nanotechnology are leading to a rapid proliferation of new materials that are likely to become a source of engineered nanoparticles (ENPs) to the environment, where their possible ecotoxicological impacts remain unknown. The surface properties of ENPs are of essential importance for their aggregation behavior, and thus for their mobility in aquatic and terrestrial systems and for their interactions with algae, plants and, fungi. Interactions of ENPs with natural organic matter have to be considered as well, as those will alter the ENPs aggregation behavior in surface waters or in soils. Cells of plants, algae, and fungi possess cell walls that constitute a primary site for interaction and a barrier for the entrance of ENPs. Mechanisms allowing ENPs to pass through cell walls and membranes are as yet poorly understood. Inside cells, ENPs might directly provoke alterations of membranes and other cell structures and molecules, as well as protective mechanisms. Indirect effects of ENPs depend on their chemical and physical properties and may include physical restraints (clogging effects), solubilization of toxic ENP compounds, or production of reactive oxygen species. Many questions regarding the bioavailability of ENPs, their uptake by algae, plants, and fungi and the toxicity mechanisms remain to be elucidated.

  8. Mechanistic approaches for evaluating the toxicity of reactive organochlorines and epoxides in green algae.

    Science.gov (United States)

    Niederer, Christian; Behra, Renata; Harder, Angela; Schwarzenbach, René P; Escher, Beate I

    2004-03-01

    Reactive electrophilic chemicals, such as reactive organochlorine compounds or epoxides, react specifically with a broad spectrum of nucleophilic biomolecules, including proteins and DNA. Conventional toxicity tests for algae, involving the observation of growth inhibition, i.e., the inhibition of cell multiplication, after several days, yield unreliable information for risk assessment because reactive compounds hydrolyze to different extents during the exposure period. The diversity of their modes of toxic action further complicates effect assessment and calls for methods yielding additional information on the mechanisms of toxicity. One of the primary targets of reactive chemicals in cells is the tripeptide glutathione (GSH), which is important for detoxification but can also be regarded as a toxicity sensor because changes in glutathione levels indicate stress. A vital system for algae is the photosynthetic system, which is indirectly affected by reactive chemicals. The test systems developed in this study for the assessment of reactive toxicity toward algae were therefore based not only on nonspecific toxicity indicators like growth inhibition but also on indicators for disturbance of photosynthesis (inhibition of photosystem II quantum yield) and glutathione metabolism. The application of the developed test systems on Scenedesmus vacuolatus after short-term exposure of 2 h showed that these tests can be used as fast screening tests for algal toxicity and in mode-of-action-based test batteries.

  9. Microbial deposition of gold nanoparticles by the metal-reducing bacterium Shewanella algae

    International Nuclear Information System (INIS)

    Konishi, Y.; Tsukiyama, T.; Tachimi, T.; Saitoh, N.; Nomura, T.; Nagamine, S.

    2007-01-01

    Microbial reduction and deposition of gold nanoparticles was achieved at 25 deg. C over the pH range 2.0-7.0 using the mesophilic bacterium Shewanella algae in the presence of H 2 as the electron donor. The reductive deposition of gold by the resting cells of S. algae was a fast process: 1 mM AuCl 4 - ions were completely reduced to elemental gold within 30 min. At a solution pH of 7, gold nanoparticles 10-20 nm in size were deposited in the periplasmic space of S. algae cells. At pH 2.8, gold nanoparticles 15-200 nm in size were deposited on the bacterial cells, and the biogenic nanoparticles exhibited a variety of shapes that included nanotriangles: in particular, single crystalline gold nanotriangles 100-200 nm in size were microbially deposited. At a solution pH of 2.0, gold nanoparticles about 20 nm in size were deposited intracellularly, and larger gold particles approximately 350 nm in size were deposited extracellularly. The solution pH was an important factor in controlling the morphology of the biogenic gold particles and the location of gold deposition. Microbial deposition of gold nanoparticles is potentially attractive as an environmentally friendly alternative to conventional methods

  10. On reproduction in red algae: further research needed at the molecular level

    Directory of Open Access Journals (Sweden)

    Pilar eGarcía-Jiménez

    2015-02-01

    Full Text Available Multicellular red algae (Rhodophyta have some of the most complex life cycles known in living organisms. Economically valuable seaweeds, such as phycocolloid producers, have a triphasic (gametophyte, carposporophyte and tetrasporophyte life cycle, not to mention the intricate alternation of generations in the edible sushi-alga nori. It is a well-known fact that reproductive processes are controlled by one or more abiotic factor(s, including day length, light quality, temperature and nutrients. Likewise, endogenous chemical factors such as plant growth regulators have been reported to affect reproductive events in some red seaweeds. Still, in the genomic era and given the high throughput techniques at our disposal, our knowledge about the endogenous molecular machinery lags far behind that of higher plants. Any potential effective control of the reproductive process will entail revisiting most of these results and facts to answer basic biological questions as yet unresolved. Recent results have shed light on the involvement of several genes in red alga reproductive events. In addition, a working species characterized by a simple filamentous architecture, easy cultivation and accessible genomes may also facilitate our task.

  11. Harvesting, oil extraction, and conversion of local filamentous algae growing in wastewater into biodiesel

    Energy Technology Data Exchange (ETDEWEB)

    Grayburn, W.S.; Holbrook, G.P. [Department of Biological Sciences, Northern Illinois University, DeKalb, IL 60115 (United States); Tatara, R.A. [Department of Technology, Northern Illinois University, DeKalb, IL 60115 (United States); Rosentrater, K.A. [Department of Agricultural and Biosystems Engineering, Iowa State University, Ames, IA 50011 (United States)

    2013-07-01

    Algae are known to be a potential feedstock in the production of biodiesel fuel. Although much of the focus has been on microalgal species, macroalgae are also suitable as a source of lipids. In this study, a locally abundant (central Illinois) filamentous algae has been harvested from a water treatment plant; dried to about 10% of its initial weight; pulverized in a hammermill; and treated with methanol to extract the oil. The algae are a combination of several coexisting species including Cladophora sp. and Rhizoclonium. Oil yields ranged from 3% to 6%, by weight, of the dried mass. This oil was reacted by transesterification to yield fatty acid methyl esters (biodiesel fuel) with an overall mass conversion efficiency of 68%. A B5 blend of this algal biodiesel and petrodiesel was run in a 13.4-kW test engine. Measurements indicated similar performance compared to pure petrodiesel in terms of fuel efficiency and carbon dioxide and carbon monoxide exhaust emissions. Significantly, there was a 22% reduction in nitrogen oxides when using the B5 fuel. It has been demonstrated that filamentous macroalgae may be cultivated as biodiesel feedstock and have inherent advantages such as an ability to remove phosphorus and nitrogen compounds from wastewater, simplicity of harvesting, and natural resistance to local aquatic grazers and competing organisms.

  12. Impact of Summer Cattle Grazing on the Sierra Nevada Watershed: Aquatic Algae and Bacteria

    Directory of Open Access Journals (Sweden)

    Robert W. Derlet

    2012-01-01

    Full Text Available Introduction. We evaluated periphytic algal and microbial communities to assess the influence of human and cattle impact on Sierra water quality. Methods. 64 sites (lakes and streams from Lake Tahoe to Sequoia National Park, California were sampled for suspended indicator bacteria and algae following standardized procedures. The potential for nonpoint pollution was divided into three categories: cattle-grazing areas (C, recreation use areas (R, or remote wildlife areas (W. Results. Periphyton was found at 100% of C sites, 89% of R sites, but only 25% of W sites. Eleven species of periphytic algae were identified, including Zygnema, Ulothrix, Chlorella, Spirogyra, mixed Diatoms, and Cladophoria. Mean benthic algae coverage was 66% at C sites compared to 2% at W sites (100 CFU/100 mL: C = 91%, R = 8%, W = 0 (<0.05. Conclusion. Higher periphytic algal biomass and uniform presence of periphyton-attached E. coli corresponded to watersheds exposed to summer cattle grazing. These differences suggest cattle grazing compromises water quality.

  13. The value of algae as a substrate for intertidal invertebrates in the White Sea

    Directory of Open Access Journals (Sweden)

    Chovgan O. V.

    2017-06-01

    Full Text Available The paper is devoted to researching zoobenthos communities of the intertidal zone, where the role of the substrate is represented by littoral phytobenthos. Macrophytes are subject to changes in time and are part of the trophic structure of marine communities as comparing with an inert ground substrate. The comprehensive study of littoral biocenoses allows reveal interrelation of benthic organisms with the vegetable substrate where they inhabit. The aim of the work is the investigation of structure and distribution features of epibenthic communities on the littoral macrophytes of the Chupa inlet (the White Sea. The investigations were conducted at The White Sea Biological Station "Kartesh" (WSBS during the summer period of three years (2012–2015. The material was being collected on the intertidal zone of the Levaya bay, Kruglaya bay, and Sel'dyanaya bay of the Chupa inlet by the method of vertical transects using the accounting frame (0.25 m2 in the three-fold repetition. In the processing of samples, the abundance of algae and epibionts has been defined; the biomass and number of macrophytes and invertebrates have been measured. In the course of the work, it has been revealed that Fucus algae create a favorable habitat for epibenthos including moving animals. A variety of seaweed substrates contributes to increase of invertebrates' biomass. The only exceptions are parts of the bays, where seaweed Ascophyllum nodosum and Pelvetia caniculata are abundant. These algae are not favourable substrate for most of epibenthic organisms and serve as habitat mainly of sedentary invertebrates due to the morphology of the thallus. Mussels Mytilus edulis are dominant invertebrates in the communities, where Fucus is the substrate. Filamentous algae contribute to active development of Hydrobia ulvae communities.

  14. Crustose coralline algae and associated microbial biofilms deter seaweed settlement on coral reefs

    Science.gov (United States)

    Gomez-Lemos, Luis A.; Diaz-Pulido, Guillermo

    2017-06-01

    Crustose coralline algae (CCA), a group of calcifying red algae found commonly in benthic marine ecosystems worldwide, perform essential ecological functions on coral reefs, including creating benthic substrate, stabilizing the reef structure and inducing coral settlement. An important feature of CCA is the ability to keep their surfaces free of epiphytic algae, thereby reducing algal overgrowth and allowing them access to light. However, the mechanisms by which CCA prevent settlement of opportunistic seaweeds (fleshy macroalgae) are not fully understood, nor is whether these mechanisms vary among CCA species. In our study based on the Great Barrier Reef, we demonstrate that three common CCA species ( Titanoderma pustulatum, Porolithon onkodes and Neogoniolithon sp.) have a remarkable ability to deter settlement of seaweed spores. We provide experimental evidence that the CCA use allelopathy and microbial inhibition against the settlement of spores of the brown seaweed Padina boergesenii. Methanol extracts of allelopathic compounds from T. pustulatum, Po. onkodes and Neogoniolithon sp. significantly reduced the settlement of Pa. boergesenii spores by 4.3 times, 3.0 and 3.8 times, respectively. Further, we found that microbial biofilms, while having a lower inhibitory effect than allelopathic compounds, also reduced seaweed settlement of Pa. boergesenii. Our study demonstrates that allelopathy and microbial inhibition, in addition to epithallial tissue sloughing, are mechanisms employed by CCA to prevent the settlement of epiphytic algae. Understanding the mechanisms by which CCA avoid seaweed overgrowth contributes to our understanding of the dynamics of seaweed proliferations on reefs and to the ecological knowledge of this important group of reef-building organisms.

  15. Origin and evolution of chloroplast group I introns in lichen algae.

    Science.gov (United States)

    Del Hoyo, Alicia; Álvarez, Raquel; Gasulla, Francisco; Casano, Leonardo Mario; Del Campo, Eva María

    2018-02-01

    The history of group I introns is characterized by repeated horizontal transfers, even among phylogenetically distant species. The symbiogenetic thalli of lichens are good candidates for the horizontal transfer of genetic material among distantly related organisms, such as fungi and green algae. The main goal of this study was to determine whether there were different trends in intron distribution and properties among Chlorophyte algae based on their phylogenetic relationships and living conditions. Therefore, we investigated the occurrence, distribution and properties of group I introns within the chloroplast LSU rDNA in 87 Chlorophyte algae including lichen and free-living Trebouxiophyceae compared to free-living non-Trebouxiophyceae species. Overall, our findings showed that there was high diversity of group I introns and homing endonucleases (HEs) between Trebouxiophyceae and non-Trebouxiophyceae Chlorophyte algae, with divergence in their distribution patterns, frequencies and properties. However, the differences between lichen Trebouxiophyceae and free-living Trebouxiophyceae were smaller. An exception was the cL2449 intron, which was closely related to ω elements in yeasts. Such introns seem to occur more frequently in lichen Trebouxiophyceae compared to free-living Trebouxiophyceae. Our data suggest that lichenization and maintenance of lichen symbiosis for millions of years of evolution may have facilitated horizontal transfers of specific introns/HEs between symbionts. The data also suggest that sequencing of more chloroplast genes harboring group I introns in diverse algal groups may help us to understand the group I intron/HE transmission process within these organisms. © 2017 Phycological Society of America.

  16. Defluviitalea phaphyphila sp. nov., a Novel Thermophilic Bacterium That Degrades Brown Algae.

    Science.gov (United States)

    Ji, Shi-Qi; Wang, Bing; Lu, Ming; Li, Fu-Li

    2016-02-01

    Brown algae are one of the largest groups of oceanic primary producers for CO2 removal and carbon sinks for coastal regions. However, the mechanism for brown alga assimilation remains largely unknown in thermophilic microorganisms. In this work, a thermophilic alginolytic community was enriched from coastal sediment, from which an obligate anaerobic and thermophilic bacterial strain, designated Alg1, was isolated. Alg1 shared a 16S rRNA gene identity of 94.6% with Defluviitalea saccharophila LIND6LT2(T). Phenotypic, chemotaxonomic, and phylogenetic studies suggested strain Alg1 represented a novel species of the genus Defluviitalea, for which the name Defluviitalea phaphyphila sp. nov. is proposed. Alg1 exhibited an intriguing ability to convert carbohydrates of brown algae, including alginate, laminarin, and mannitol, to ethanol and acetic acid. Three gene clusters participating in this process were predicted to be in the genome, and candidate enzymes were successfully expressed, purified, and characterized. Six alginate lyases were demonstrated to synergistically deconstruct alginate into unsaturated monosaccharide, followed by one uronic acid reductase and two 2-keto-3-deoxy-d-gluconate (KDG) kinases to produce pyruvate. A nonclassical mannitol 1-phosphate dehydrogenase, catalyzing D-mannitol 1-phosphate to fructose 1-phosphate in the presence of NAD(+), and one laminarase also were disclosed. This work revealed that a thermophilic brown alga-decomposing system containing numerous novel thermophilic alginate lyases and a unique mannitol 1-phosphate dehydrogenase was adopted by the natural ethanologenic strain Alg1 during the process of evolution in hostile habitats. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  17. Effects of reduced dissolved oxygen concentrations on physiology and fluorescence of hermatypic corals and benthic algae.

    Science.gov (United States)

    Haas, Andreas F; Smith, Jennifer E; Thompson, Melissa; Deheyn, Dimitri D

    2014-01-01

    While shifts from coral to seaweed dominance have become increasingly common on coral reefs and factors triggering these shifts successively identified, the primary mechanisms involved in coral-algae interactions remain unclear. Amongst various potential mechanisms, algal exudates can mediate increases in microbial activity, leading to localized hypoxic conditions which may cause coral mortality in the direct vicinity. Most of the processes likely causing such algal exudate induced coral mortality have been quantified (e.g., labile organic matter release, increased microbial metabolism, decreased dissolved oxygen availability), yet little is known about how reduced dissolved oxygen concentrations affect competitive dynamics between seaweeds and corals. The goals of this study were to investigate the effects of different levels of oxygen including hypoxic conditions on a common hermatypic coral Acropora yongei and the common green alga Bryopsis pennata. Specifically, we examined how photosynthetic oxygen production, dark and daylight adapted quantum yield, intensity and anatomical distribution of the coral innate fluorescence, and visual estimates of health varied with differing background oxygen conditions. Our results showed that the algae were significantly more tolerant to extremely low oxygen concentrations (2-4 mg L(-1)) than corals. Furthermore corals could tolerate reduced oxygen concentrations, but only until a given threshold determined by a combination of exposure time and concentration. Exceeding this threshold led to rapid loss of coral tissue and mortality. This study concludes that hypoxia may indeed play a significant role, or in some cases may even be the main cause, for coral tissue loss during coral-algae interaction processes.

  18. Effects of reduced dissolved oxygen concentrations on physiology and fluorescence of hermatypic corals and benthic algae

    Directory of Open Access Journals (Sweden)

    Andreas F. Haas

    2014-01-01

    Full Text Available While shifts from coral to seaweed dominance have become increasingly common on coral reefs and factors triggering these shifts successively identified, the primary mechanisms involved in coral-algae interactions remain unclear. Amongst various potential mechanisms, algal exudates can mediate increases in microbial activity, leading to localized hypoxic conditions which may cause coral mortality in the direct vicinity. Most of the processes likely causing such algal exudate induced coral mortality have been quantified (e.g., labile organic matter release, increased microbial metabolism, decreased dissolved oxygen availability, yet little is known about how reduced dissolved oxygen concentrations affect competitive dynamics between seaweeds and corals. The goals of this study were to investigate the effects of different levels of oxygen including hypoxic conditions on a common hermatypic coral Acropora yongei and the common green alga Bryopsis pennata. Specifically, we examined how photosynthetic oxygen production, dark and daylight adapted quantum yield, intensity and anatomical distribution of the coral innate fluorescence, and visual estimates of health varied with differing background oxygen conditions. Our results showed that the algae were significantly more tolerant to extremely low oxygen concentrations (2–4 mg L−1 than corals. Furthermore corals could tolerate reduced oxygen concentrations, but only until a given threshold determined by a combination of exposure time and concentration. Exceeding this threshold led to rapid loss of coral tissue and mortality. This study concludes that hypoxia may indeed play a significant role, or in some cases may even be the main cause, for coral tissue loss during coral-algae interaction processes.

  19. Presence of skeletal banding in a reef-building tropical crustose coralline alga.

    Directory of Open Access Journals (Sweden)

    Bonnie Lewis

    Full Text Available The presence of banding in the skeleton of coralline algae has been reported in many species, primarily from temperate and polar regions. Similar to tree rings, skeletal banding can provide information on growth rate, age, and longevity; as well as records of past environmental conditions and the coralline alga's growth responses to such changes. The aim of this study was to explore the presence and characterise the nature of banding in the tropical coralline alga Porolithon onkodes, an abundant and key reef-building species on the Great Barrier Reef (GBR Australia, and the Indo-Pacific in general. To achieve this we employed various methods including X-ray diffraction (XRD to determine seasonal mol% magnesium (Mg, mineralogy mapping to investigate changes in dominant mineral phases, scanning electron microscopy-electron dispersive spectroscopy (SEM-EDS, and micro-computed tomography (micro-CT scanning to examine changes in cell size and density banding, and UV light to examine reproductive (conceptacle banding. Seasonal variation in the Mg content of the skeleton did occur and followed previously recorded variations with the highest mol% MgCO3 in summer and lowest in winter, confirming the positive relationship between seawater temperature and mol% MgCO3. Rows of conceptacles viewed under UV light provided easily distinguishable bands that could be used to measure vertical growth rate (1.4 mm year-1 and age of the organism. Micro-CT scanning showed obvious banding patterns in relation to skeletal density, and mineralogical mapping revealed patterns of banding created by changes in Mg content. Thus, we present new evidence for seasonal banding patterns in the tropical coralline alga P. onkodes. This banding in the P. onkodes skeleton can provide valuable information into the present and past life history of this important reef-building species, and is essential to assess and predict the response of these organisms to future climate and

  20. Two-Step Evolution of Endosymbiosis between Hydra and Algae

    KAUST Repository

    Ishikawa, Masakazu

    2016-07-09

    In the Hydra vulgaris group, only 2 of the 25 strains in the collection of the National Institute of Genetics in Japan currently show endosymbiosis with green algae. However, whether the other non-symbiotic strains also have the potential to harbor algae remains unknown. The endosymbiotic potential of non-symbiotic strains that can harbor algae may have been acquired before or during divergence of the strains. With the aim of understanding the evolutionary process of endosymbiosis in the H. vulgaris group, we examined the endosymbiotic potential of non-symbiotic strains of the H. vulgaris group by artificially introducing endosymbiotic algae. We found that 12 of the 23 non-symbiotic strains were able to harbor the algae until reaching the grand-offspring through the asexual reproduction by budding. Moreover, a phylogenetic analysis of mitochondrial genome sequences showed that all the strains with endosymbiotic potential grouped into a single cluster (cluster γ). This cluster contained two strains (J7 and J10) that currently harbor algae; however, these strains were not the closest relatives. These results suggest that evolution of endosymbiosis occurred in two steps; first, endosymbiotic potential was gained once in the ancestor of the cluster γ lineage; second, strains J7 and J10 obtained algae independently after the divergence of the strains. By demonstrating the evolution of the endosymbiotic potential in non-symbiotic H. vulgaris group strains, we have clearly distinguished two evolutionary steps. The step-by-step evolutionary process provides significant insight into the evolution of endosymbiosis in cnidarians.

  1. [Toxicity of Coptis chinensis Rhizome Extracts to Green Algae].

    Science.gov (United States)

    Chen, Ya-nan; Yuan, Ling

    2015-05-01

    Coptis chinensis contains antiseptic alkaloids and thus its rhizomes and preparations are widely used for the treatment of.fish diseases. In order to realize the risk of water ecosystems produced by this medical herb and preparations used in aquaculture, the present experiment was carried out to study the toxicity of Coptis chinensis rhizome extract (CRE) to Scenedesmus oblique and Chlorella pyrenoidosa grown in culture solution with 0.00 (CK), 0.088 (Tl), 0.44 (T2) and 1.76 mg · L(-1) (T3) of CRE, respectively. The results show that low concentration of CRE (T1) inhibited the growth rate of the alga and high CRE (T2 and T3) ceased growth and reproductions. CRE also decreased the chlorophyll and proteins in alga cells, indicating the inhibition of photosynthesis and protein biosynthesis, which could be direct reasons for the low growth rate and death of green alga. The efflux of protons and substances from alga cells led to pH reduction and conductivity increment in culture solution with CRE. Furthermore, the activity of superoxide dismutase in alga increased at the beginning of CRE in T1 and T2 treatments but decreased as time prolonged which was in contrast to high CRE treatment. And the long exposure to low CRE treatment behaved otherwise. This suggests that the low concentration of CRE could induce the resistant reactions in alga at initial time but high CRE concentration or long exposure even at low CRE concentration could inhibit the enzyme synthesis. Similarly, malondialdehyde in alga increased as CRE concentrations increased in culture solutions, implying the damage and high permeability of cell membrane. In general, Chlorella pyrenoidosa was more sensitive to CRE. The abuse of rhizomes and preparations in aquaculture and intensive cultivation of Coptis chinensis plants in a large scale might produce ecological risks to primary productivity of water ecosystems.

  2. Two-step evolution of endosymbiosis between hydra and algae.

    Science.gov (United States)

    Ishikawa, Masakazu; Shimizu, Hiroshi; Nozawa, Masafumi; Ikeo, Kazuho; Gojobori, Takashi

    2016-10-01

    In the Hydra vulgaris group, only 2 of the 25 strains in the collection of the National Institute of Genetics in Japan currently show endosymbiosis with green algae. However, whether the other non-symbiotic strains also have the potential to harbor algae remains unknown. The endosymbiotic potential of non-symbiotic strains that can harbor algae may have been acquired before or during divergence of the strains. With the aim of understanding the evolutionary process of endosymbiosis in the H. vulgaris group, we examined the endosymbiotic potential of non-symbiotic strains of the H. vulgaris group by artificially introducing endosymbiotic algae. We found that 12 of the 23 non-symbiotic strains were able to harbor the algae until reaching the grand-offspring through the asexual reproduction by budding. Moreover, a phylogenetic analysis of mitochondrial genome sequences showed that all the strains with endosymbiotic potential grouped into a single cluster (cluster γ). This cluster contained two strains (J7 and J10) that currently harbor algae; however, these strains were not the closest relatives. These results suggest that evolution of endosymbiosis occurred in two steps; first, endosymbiotic potential was gained once in the ancestor of the cluster γ lineage; second, strains J7 and J10 obtained algae independently after the divergence of the strains. By demonstrating the evolution of the endosymbiotic potential in non-symbiotic H. vulgaris group strains, we have clearly distinguished two evolutionary steps. The step-by-step evolutionary process provides significant insight into the evolution of endosymbiosis in cnidarians. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Investigating the feasibility of growing algae for fuel in Southern nevada

    Science.gov (United States)

    Moazeni, Faegheh

    Microalgae capable of growing in waste are adequate to be mass-cultivated for biodiesel, avoiding fertilizers and clean water, two obstacles to sustainability of the feedstock production. This study replaces fertilizers and clean water with waste products. The investigated wastes include (1) the liquid fraction of sewage after solids and particles are removed, known as centrate, and (2) algal biomass residue, i.e. the algae remaining at the end of the lipids extraction process at biofuel plants. These wastes contain sufficient amount of nitrogen and phosphorus required for algal growth. This study proposes a system in which centrate would be used as an initial source of water and nutrients for microalgal growth. The generated biomass waste can be continuously recycled, serving as a fertilizer. If so desired, the centrate can be reverted back into the system from time to time as a nutrition supplement and as a make-up water source, particularly in open ponds that face evaporation. Of the six studied algae, i.e. Chlorella sorokiniana, Encyonema caespitosum, Nitzschia thermalis, Scenedesmus sp., Synechocystis sp., and Limnothrix sp., mostly isolated from the habitats influenced by municipal wastewater in and around the Las Vegas Valley, two green algae were eligible. In the laboratory, the green algae C. sorokiniana and Scenedesmus sp. grew in the media composed of centrate or algal residue faster than in the mineral medium BG11, optimized for algal growth. The enhanced productivity is mainly attributed to the photosynthesis known for mixotrophic process and the presence of organic carbon in the waste which serves as an extra source of energy. Tolerance for hard water and strong light and, in the case of C. sorokiniana , an unusually high optimum temperature between 32 and 35°C are also attributing factors to the enhanced productivity of algae. These studied species are particularly suited for cultivation in their native southwestern United States, particularly

  4. Marine Algae as Source of Novel Antileishmanial Drugs: A Review

    Directory of Open Access Journals (Sweden)

    Lauve Rachel Tchokouaha Yamthe

    2017-10-01

    Full Text Available Leishmaniasis is a vector-borne neglected tropical disease caused by protozoan parasites of the Leishmania genus and transmitted by the female Phlebotomus and Lutzomyia sand flies. The currently prescribed therapies still rely on pentavalent antimonials, pentamidine, paromomycin, liposomal amphotericin B, and miltefosine. However, their low efficacy, long-course treatment regimen, high toxicity, adverse side effects, induction of parasite resistance and high cost require the need for better drugs given that antileishmanial vaccines may not be available in the near future. Although most drugs are still derived from terrestrial sources, the interest in marine organisms as a potential source of promising novel bioactive natural agents has increased in recent years. About 28,000 compounds of marine origin have been isolated with hundreds of new chemical entities. Recent trends in drug research from natural resources indicated the high interest of aquatic eukaryotic photosynthetic organisms, marine algae in the search for new chemical entities given their broad spectrum and high bioactivities including antileishmanial potential. This current review describes prepared extracts and compounds from marine macroalgae along with their antileishmanial activity and provides prospective insights for antileishmanial drug discovery.

  5. In vivo localization studies in the stramenopile alga Nannochloropsis oceanica.

    Science.gov (United States)

    Moog, Daniel; Stork, Simone; Reislöhner, Sven; Grosche, Christopher; Maier, Uwe-G

    2015-02-01

    The tiny eustigmatophyte Nannochloropsis sp. recently emerged as a promising model organism for biotechnology as it possesses a considerably high cellular oil content interesting for biodiesel production. Furthermore, the alga was shown to be genetically well accessible providing powerful tools for biotechnological engineering as well as basic research. Nannochloropsis sp. can be transformed very efficiently taking advantage of homologous recombination, however, so far it remained unclear whether these organisms are also suitable model systems for in vivo protein localization studies due to their small cell size. Here we present, to our knowledge, the first protein localization studies based on the expression of chimeric fluorescent fusion proteins in the genus Nannochloropsis using N. oceanica CCMP1779 as a model organism. Besides expressing a cytosolic green fluorescent protein (GFP), the reporter could be directed into subcellular structures such as the mitochondria, the endoplasmic reticulum and secretory pathway as well as the complex plastid including the periplastidal compartment and the stroma via fusion of specific N-terminal targeting sequences. These results expand the potential of N. oceanica as a model system in biotechnology as well as cellular biology for which now an almost complete molecular tool set exists. Copyright © 2015 Elsevier GmbH. All rights reserved.

  6. An improved method for karyotype analyses of marine algae

    Science.gov (United States)

    Wang, Juan; Dai, Jixun

    2008-05-01

    Modified carbol fuchsin staining method was successfully introduced into the karyotype analyses of marine algae, including Porphyra, Undaria pinnatifida and Laminaria japonica. Haploid chromosomes were numbered clearly in the vegetative, spermatangial and conchosporangial cells of P. haitanensis and P. yezoensis. Diploid chromosomes were observed and numbered in immature conchosporangial cells of P. haitanensis and P. yezoensis. Pit-connections of Porphyra were also clearly demonstrated. Prophase chromosomes of conchocelis cells were also clearly stained with modified carbol fuchsin. One molar per liter hydrochloric hydrolysis at 60°C for 7-8 min is necessary for getting transparent cytoplasm for conchosporangial karyotype analysis of Porphyra. Staining effects of the three methods using iron alum acetocarmine, aceto-iron-haematoxylin-chloral hydrate and modified carbol fuchsin were compared on the vegetative, spermatangial and conchosporangial cells of Porphyra and the gametophytes of U. pinnatifida and L. japonica. Among the three methods, the modified carbol fuchsin method gave the best result of deep staining and good contrast between nucleus and cytoplasm.

  7. Marine Algae as Source of Novel Antileishmanial Drugs: A Review.

    Science.gov (United States)

    Tchokouaha Yamthe, Lauve Rachel; Appiah-Opong, Regina; Tsouh Fokou, Patrick Valere; Tsabang, Nole; Fekam Boyom, Fabrice; Nyarko, Alexander Kwadwo; Wilson, Michael David

    2017-10-29

    Leishmaniasis is a vector-borne neglected tropical disease caused by protozoan parasites of the Leishmania genus and transmitted by the female Phlebotomus and Lutzomyia sand flies. The currently prescribed therapies still rely on pentavalent antimonials, pentamidine, paromomycin, liposomal amphotericin B, and miltefosine. However, their low efficacy, long-course treatment regimen, high toxicity, adverse side effects, induction of parasite resistance and high cost require the need for better drugs given that antileishmanial vaccines may not be available in the near future. Although most drugs are still derived from terrestrial sources, the interest in marine organisms as a potential source of promising novel bioactive natural agents has increased in recent years. About 28,000 compounds of marine origin have been isolated with hundreds of new chemical entities. Recent trends in drug research from natural resources indicated the high interest of aquatic eukaryotic photosynthetic organisms, marine algae in the search for new chemical entities given their broad spectrum and high bioactivities including antileishmanial potential. This current review describes prepared extracts and compounds from marine macroalgae along with their antileishmanial activity and provides prospective insights for antileishmanial drug discovery.

  8. Proteomics analysis of heterogeneous flagella in brown algae (stramenopiles).

    Science.gov (United States)

    Fu, Gang; Nagasato, Chikako; Oka, Seiko; Cock, J Mark; Motomura, Taizo

    2014-09-01

    Flagella are conserved organelles among eukaryotes and they are composed of many proteins, which are necessary for flagellar assembly, maintenance and function. Stramenopiles, which include brown algae, diatoms and oomycetes, possess two laterally inserted flagella. The anterior flagellum (AF) extends forward and bears tripartite mastigonemes, whilst the smooth posterior flagellum (PF) often has a paraflagellar body structure. These heterogeneous flagella have served as crucial structures in algal studies especially from a viewpoint of phylogeny. However, the protein compositions of the flagella are still largely unknown. Here we report a LC-MS/MS based proteomics analysis of brown algal flagella. In total, 495 flagellar proteins were identified. Functional annotation of the proteome data revealed that brown algal flagellar proteins were associated with cell motility, signal transduction and various metabolic activities. We separately isolated AF and PF and analyzed their protein compositions. This analysis led to the identification of several AF- and PF-specific proteins. Among the PF-specific proteins, we found a candidate novel blue light receptor protein involved in phototaxis, and named it HELMCHROME because of the steering function of PF. Immunological analysis revealed that this protein was localized along the whole length of the PF and concentrated in the paraflagellar body. Copyright © 2014 Elsevier GmbH. All rights reserved.

  9. Marine Algae as Source of Novel Antileishmanial Drugs: A Review

    Science.gov (United States)

    Tchokouaha Yamthe, Lauve Rachel; Appiah-Opong, Regina; Tsabang, Nole; Nyarko, Alexander Kwadwo

    2017-01-01

    Leishmaniasis is a vector-borne neglected tropical disease caused by protozoan parasites of the Leishmania genus and transmitted by the female Phlebotomus and Lutzomyia sand flies. The currently prescribed therapies still rely on pentavalent antimonials, pentamidine, paromomycin, liposomal amphotericin B, and miltefosine. However, their low efficacy, long-course treatment regimen, high toxicity, adverse side effects, induction of parasite resistance and high cost require the need for better drugs given that antileishmanial vaccines may not be available in the near future. Although most drugs are still derived from terrestrial sources, the interest in marine organisms as a potential source of promising novel bioactive natural agents has increased in recent years. About 28,000 compounds of marine origin have been isolated with hundreds of new chemical entities. Recent trends in drug research from natural resources indicated the high interest of aquatic eukaryotic photosynthetic organisms, marine algae in the search for new chemical entities given their broad spectrum and high bioactivities including antileishmanial potential. This current review describes prepared extracts and compounds from marine macroalgae along with their antileishmanial activity and provides prospective insights for antileishmanial drug discovery. PMID:29109372

  10. Triassic origin and early radiation of multicellular volvocine algae.

    Science.gov (United States)

    Herron, Matthew D; Hackett, Jeremiah D; Aylward, Frank O; Michod, Richard E

    2009-03-03

    Evolutionary transitions in individuality (ETIs) underlie the watershed events in the history of life on Earth, including the origins of cells, eukaryotes, plants, animals, and fungi. Each of these events constitutes an increase in the level of complexity, as groups of individuals become individuals in their own right. Among the best-studied ETIs is the origin of multicellularity in the green alga Volvox, a model system for the evolution of multicellularity and cellular differentiation. Since its divergence from unicellular ancestors, Volvox has evolved into a highly integrated multicellular organism with cellular specialization, a complex developmental program, and a high degree of coordination among cells. Remarkably, all of these changes were previously thought to have occurred in the last 50-75 million years. Here we estimate divergence times using a multigene data set with multiple fossil calibrations and use these estimates to infer the times of developmental changes relevant to the evolution of multicellularity. Our results show that Volvox diverged from unicellular ancestors at least 200 million years ago. Two key innovations resulting from an early cycle of cooperation, conflict and conflict mediation led to a rapid integration and radiation of multicellular forms in this group. This is the only ETI for which a detailed timeline has been established, but multilevel selection theory predicts that similar changes must have occurred during other ETIs.

  11. Optimal control of algae growth by controlling CO 2 and nutrition flow using Pontryagin Maximum Principle

    Science.gov (United States)

    Mardlijah; Jamil, Ahmad; Hanafi, Lukman; Sanjaya, Suharmadi

    2017-09-01

    There are so many benefit of algae. One of them is using for renewable energy and sustainable in the future. The greater growth of algae will increasing biodiesel production and the increase of algae growth is influenced by glucose, nutrients and photosynthesis process. In this paper, the optimal control problem of the growth of algae is discussed. The objective function is to maximize the concentration of dry algae while the control is the flow of carbon dioxide and the nutrition. The solution is obtained by applying the Pontryagin Maximum Principle. and the result show that the concentration of algae increased more than 15 %.

  12. Algae-bacteria interactions: Evolution, ecology and emerging applications.

    Science.gov (United States)

    Ramanan, Rishiram; Kim, Byung-Hyuk; Cho, Dae-Hyun; Oh, Hee-Mock; Kim, Hee-Sik

    2016-01-01

    Algae and bacteria have coexisted ever since the early stages of evolution. This coevolution has revolutionized life on earth in many aspects. Algae and bacteria together influence ecosystems as varied as deep seas to lichens and represent all conceivable modes of interactions - from mutualism to parasitism. Several studies have shown that algae and bacteria synergistically affect each other's physiology and metabolism, a classic case being algae-roseobacter interaction. These interactions are ubiquitous and define the primary productivity in most ecosystems. In recent years, algae have received much attention for industrial exploitation but their interaction with bacteria is often considered a contamination during commercialization. A few recent studies have shown that bacteria not only enhance algal growth but also help in flocculation, both essential processes in algal biotechnology. Hence, there is a need to understand these interactions from an evolutionary and ecological standpoint, and integrate this understanding for industrial use. Here we reflect on the diversity of such relationships and their associated mechanisms, as well as the habitats that they mutually influence. This review also outlines the role of these interactions in key evolutionary events such as endosymbiosis, besides their ecological role in biogeochemical cycles. Finally, we focus on extending such studies on algal-bacterial interactions to various environmental and bio-technological applications. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  13. Overcoming Microalgae Harvesting Barrier by Activated Algae Granules.

    Science.gov (United States)

    Tiron, Olga; Bumbac, Costel; Manea, Elena; Stefanescu, Mihai; Nita Lazar, Mihai

    2017-07-05

    The economic factor of the microalgae harvesting step acts as a barrier to scaling up microalgae-based technology designed for wastewater treatment. In view of that, this study presents an alternative microalgae-bacteria system, which is proposed for eliminating the economic obstacle. Instead of the microalgae-bacteria (activated algae) flocs, the study aimed to develop activated algae granules comprising the microalgae Chlorella sp. as a target species. The presence of the filamentous microalgae (Phormidium sp.) was necessary for the occurrence of the granulation processes. A progressive decrease in frequency of the free Chlorella sp. cells was achieved once with the development of the activated algae granules as a result of the target microalgae being captured in the dense and tangled network of filaments. The mature activated algae granules ranged between 600 and 2,000 µm, and were characterized by a compact structure and significant settling ability (21.6 ± 0.9 m/h). In relation to the main aim of this study, a microalgae recovery efficiency of higher than 99% was achieved only by fast sedimentation of the granules; this performance highlighted the viability of the granular activated algae system for sustaining a microalgae harvesting procedure with neither cost nor energy inputs.

  14. Development and characteristics of an adhesion bioassay for ectocarpoid algae.

    Science.gov (United States)

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

    2012-01-01

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

  15. Algae Production from Wastewater Resources: An Engineering and Cost Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Schoenung, Susan [Longitude 122 West, Inc.; Efroymson, Rebecca Ann [ORNL

    2018-03-01

    Co-locating algae cultivation ponds near municipal wastewater (MWW) facilities provides the opportunity to make use of the nitrogen and phosphorus compounds in the wastewater as nutrient sources for the algae. This use benefits MWW facilities, the algae biomass and biofuel or bioproduct industry, and the users of streams where treated or untreated waste would be discharged. Nutrient compounds can lead to eutrophication, hypoxia, and adverse effects to some organisms if released downstream. This analysis presents an estimate of the cost savings made possible to cultivation facilities by using the nutrients from wastewater for algae growth rather than purchase of the nutrients. The analysis takes into consideration the cost of pipe transport from the wastewater facility to the algae ponds, a cost factor that has not been publicly documented in the past. The results show that the savings in nutrient costs can support a wastewater transport distance up to 10 miles for a 1000-acre-pond facility, with potential adjustments for different operating assumptions.

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

    Science.gov (United States)

    Jiménez, Edra; Dorta, Fernando; Medina, Cristian; Ramírez, Alberto; Ramírez, Ingrid; Peña-Cortés, Hugo

    2011-01-01

    Aqueous and ethanolic extracts obtained from nine Chilean marine macro-algae collected at different seasons were examined in vitro and in vivo for properties that reduce the growth of plant pathogens or decrease the injury severity of plant foliar tissues following pathogen infection. Particular crude aqueous or organic extracts showed effects on the growth of pathogenic bacteria whereas others displayed important effects against pathogenic fungi or viruses, either by inhibiting fungal mycelia growth or by reducing the disease symptoms in leaves caused by pathogen challenge. Organic extracts obtained from the brown-alga Lessonia trabeculata inhibited bacterial growth and reduced both the number and size of the necrotic lesion in tomato leaves following infection with Botrytis cinerea. Aqueous and ethanolic extracts from the red-alga Gracillaria chilensis prevent the growth of Phytophthora cinnamomi, showing a response which depends on doses and collecting-time. Similarly, aqueous and ethanolic extracts from the brown-alga Durvillaea antarctica were able to diminish the damage caused by tobacco mosaic virus (TMV) in tobacco leaves, and the aqueous procedure is, in addition, more effective and seasonally independent. These results suggest that macro-algae contain compounds with different chemical properties which could be considered for controlling specific plant pathogens.

  17. Boron uptake, localization, and speciation in marine brown algae.

    Science.gov (United States)

    Miller, Eric P; Wu, Youxian; Carrano, Carl J

    2016-02-01

    In contrast to the generally boron-poor terrestrial environment, the concentration of boron in the marine environment is relatively high (0.4 mM) and while there has been extensive interest in its use as a surrogate of pH in paleoclimate studies in the context of climate change-related questions, the relatively depth independent, and the generally non-nutrient-like concentration profile of this element have led to boron being neglected as a potentially biologically relevant element in the ocean. Among the marine plant-like organisms the brown algae (Phaeophyta) are one of only five lineages of photosynthetic eukaryotes to have evolved complex multicellularity. Many of unusual and often unique features of brown algae are attributable to this singular evolutionary history. These adaptations are a reflection of the marine coastal environment which brown algae dominate in terms of biomass. Consequently, brown algae are of fundamental importance to oceanic ecology, geochemistry, and coastal industry. Our results indicate that boron is taken up by a facilitated diffusion mechanism against a considerable concentration gradient. Furthermore, in both Ectocarpus and Macrocystis some boron is most likely bound to cell wall constituent alginate and the photoassimilate mannitol located in sieve cells. Herein, we describe boron uptake, speciation, localization and possible biological function in two species of brown algae, Macrocystis pyrifera and Ectocarpus siliculosus.

  18. Anti-Phytopathogenic Activities of Macro-Algae Extracts

    Directory of Open Access Journals (Sweden)

    Ingrid Ramírez

    2011-05-01

    Full Text Available 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.

  19. Evolution of reproductive development in the volvocine algae.

    Science.gov (United States)

    Hallmann, Armin

    2011-06-01

    The evolution of multicellularity, the separation of germline cells from sterile somatic cells, and the generation of a male-female dichotomy are certainly among the greatest innovations of eukaryotes. Remarkably, phylogenetic analysis suggests that the shift from simple to complex, differentiated multicellularity was not a unique progression in the evolution of life, but in fact a quite frequent event. The spheroidal green alga Volvox and its close relatives, the volvocine algae, span the full range of organizational complexity, from unicellular and colonial genera to multicellular genera with a full germ-soma division of labor and male-female dichotomy; thus, these algae are ideal model organisms for addressing fundamental issues related to the transition to multicellularity and for discovering universal rules that characterize this transition. Of all living species, Volvox carteri represents the simplest version of an immortal germline producing specialized somatic cells. This cellular specialization involved the emergence of mortality and the production of the first dead ancestors in the evolution of this lineage. Volvocine algae therefore exemplify the evolution of cellular cooperation from cellular autonomy. They also serve as a prime example of the evolution of complex traits by a few successive, small steps. Thus, we learn from volvocine algae that the evolutionary transition to complex, multicellular life is probably much easier to achieve than is commonly believed. © The Author(s) 2010. This article is published with open access at Springerlink.com

  20. Radionuclides in macro algae at Monaco following the Chernobyl accident

    International Nuclear Information System (INIS)

    Holm, E.; Ballestra, S.; Lopez, J.J.; Bulos, A.; Whitehead, N.E.; Barci-Funel, G.; Ardisson, G.

    1994-01-01

    Samples of macro algae, Codmium tomentosum (green), Corallina mediterranea (red), Sphaerococcus coronopifolius (red) and Dictyota dichotoma (brown), were collected off Monaco during 1984 and 1988 and analysed for gamma-emitting radionuclides and transuranium elements. Due to the Chernobyl accident, increased radioactivity in the atmosphere at Monaco was recorded on 30 April 1986 with maximal activity concentrations on 2-3 May. The maximal activity concentrations in sea water occurred on 5-6 May and in the algae on 11 May. The decrease of activity concentrations can be described after May 11 as a single exponential relationship, where elimination rates for different radionuclides and different species specific to the environment can be calculated. The elimination rates thus observed correspond to mean residence times between 70 and 370 days corrected for physical decay. The concentration factors were also estimated and the highest values were found for 131 I, 129 Te m , and 110 Ag m and lowest for radiocesium and 140 Ba. The red algae Sphaerococcus coronopifoius showed generally higher concentration factors than green and brown algae. Regarding transuranium elements, a theoretical contribution from the Chernobyl accident can be made but only 242 Cm was detected in the algae above previous levels before the accident, due to the relatively small fallout of transuranics. (author) 23 refs.; 9 figs.; 4 tabs

  1. Acute toxicity and associated mechanisms of four strobilurins in algae.

    Science.gov (United States)

    Liu, Xiaoxu; Wang, Yu; Chen, Hao; Zhang, Junli; Wang, Chengju; Li, Xuefeng; Pang, Sen

    2018-04-03

    Strobilurins have been reported highly toxic to non-target aquatic organisms but few illustrated how they cause toxic effects on algae. This study investigated the acute toxicity of Kresoxim-methy (KRE), Pyraclostrobin (PYR), Trifloxystrobin (TRI) and Picoxystrobin (PIC) on two algae and their toxicity mechanisms. Four strobilurins showed lower toxic effects on Chlorella pyrenoidsa but higher on Chlorella vulgaris. bc1 complex activities in C. vulgaris were significantly inhibited by all strobilurins, suggesting bc 1 complex might be the target of strobilurin toxicity in algae. Moreover, SOD, CAT and POD activities were significantly up-regulated by all doses of KRE, PYR and PIC. In contrast, low concentrations of TRI stimulated SOD and POD activities but highest concentration significantly inhibited those activities. Comet assays showed damaged DNA in C. vulgaris by four strobulirins, suggesting their potential genotoxic threats to algae. The results illustrated acute toxicity by strobulirins on algae and their possible toxicity mechanisms. Copyright © 2018 Elsevier B.V. All rights reserved.

  2. Sustainability of algae derived biodiesel: a mass balance approach.

    Science.gov (United States)

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

    2011-01-01

    A rigorous chemical engineering mass balance/unit operations approach is applied here to bio-diesel from algae mass culture. An equivalent of 50,000,000 gallons per year (0.006002 m3/s) of petroleum-based Number 2 fuel oil (US, diesel for compression-ignition engines, about 0.1% of annual US consumption) from oleaginous algae is the target. Methyl algaeate and ethyl algaeate diesel can according to this analysis conceptually be produced largely in a technologically sustainable way albeit at a lower available diesel yield. About 11 square miles of algae ponds would be needed with optimistic assumptions of 50 g biomass yield per day and m2 pond area. CO2 to foster algae growth should be supplied from a sustainable source such as a biomass-based ethanol production. Reliance on fossil-based CO2 from power plants or fertilizer production renders algae diesel non-sustainable in the long term. Copyright © 2010 Elsevier Ltd. All rights reserved.

  3. Visualization of oxygen distribution patterns caused by coral and algae.

    Science.gov (United States)

    Haas, Andreas F; Gregg, Allison K; Smith, Jennifer E; Abieri, Maria L; Hatay, Mark; Rohwer, Forest

    2013-01-01

    Planar optodes were used to visualize oxygen distribution patterns associated with a coral reef associated green algae (Chaetomorpha sp.) and a hermatypic coral (Favia sp.) separately, as standalone organisms, and placed in close proximity mimicking coral-algal interactions. Oxygen patterns were assessed in light and dark conditions and under varying flow regimes. The images show discrete high oxygen concentration regions above the organisms during lighted periods and low oxygen in the dark. Size and orientation of these areas were dependent on flow regime. For corals and algae in close proximity the 2D optodes show areas of extremely low oxygen concentration at the interaction interfaces under both dark (18.4 ± 7.7 µmol O2 L(- 1)) and daylight (97.9 ± 27.5 µmol O2 L(- 1)) conditions. These images present the first two-dimensional visualization of oxygen gradients generated by benthic reef algae and corals under varying flow conditions and provide a 2D depiction of previously observed hypoxic zones at coral algae interfaces. This approach allows for visualization of locally confined, distinctive alterations of oxygen concentrations facilitated by benthic organisms and provides compelling evidence for hypoxic conditions at coral-algae interaction zones.

  4. Visualization of oxygen distribution patterns caused by coral and algae

    Directory of Open Access Journals (Sweden)

    Andreas F. Haas

    2013-07-01

    Full Text Available Planar optodes were used to visualize oxygen distribution patterns associated with a coral reef associated green algae (Chaetomorpha sp. and a hermatypic coral (Favia sp. separately, as standalone organisms, and placed in close proximity mimicking coral-algal interactions. Oxygen patterns were assessed in light and dark conditions and under varying flow regimes. The images show discrete high oxygen concentration regions above the organisms during lighted periods and low oxygen in the dark. Size and orientation of these areas were dependent on flow regime. For corals and algae in close proximity the 2D optodes show areas of extremely low oxygen concentration at the interaction interfaces under both dark (18.4 ± 7.7 µmol O2 L- 1 and daylight (97.9 ± 27.5 µmol O2 L- 1 conditions. These images present the first two-dimensional visualization of oxygen gradients generated by benthic reef algae and corals under varying flow conditions and provide a 2D depiction of previously observed hypoxic zones at coral algae interfaces. This approach allows for visualization of locally confined, distinctive alterations of oxygen concentrations facilitated by benthic organisms and provides compelling evidence for hypoxic conditions at coral-algae interaction zones.

  5. PIXE application for multi-element analysis of marine micro-algae and measurement of the concentration factor of zinc

    International Nuclear Information System (INIS)

    Iwata, Y.

    2001-01-01

    Marine micro-algae (Nannochloropsis sp., Phaeodactylum sp., etc.) were obtained from the Pacific Ocean of Iwate Prefecture, Japan, and cultured purely in nutritive seawater, PES and artificial seawater, ASP7 as a culture solution. The algae in 5 ml of the culture solution was collected on a polycarbonate film (pore size: 1.0 μm) by suction filtration. The algae on the film was subjected to PIXE analysis. A 2.9 MeV proton beam bombarded it at 50 nA for 15 minutes. Induced X-ray was measured by Si(Li) detector. Concentrations of Na, Mg, Al, Si, P, S, Cl, K, Ca, Cr, Mn, Fe, Cu, Zn and Sr were determined simultaneously. PIXE can used for multi-element analysis of a sample below 1 mg, so the culture size for algae was 10-250 ml and every apparatus was small and of low cost. Nannochloropsis sp. was given a different culture solution (PES) including Zn 2+ from 0.050 to 1.0 mg/l and incubated at 22 deg C, 2000 lux for 10 hours. Zn in Nannochloropsis sp, increased in proportion to the Zn 2+ concentration in the culture solution. The concentration factor was given as 1600 ± 100 (wet weight base) and 9000 ± 500 (dry weight base). It was shown that PIXE was a powerful tool for multi-element analysis of micro organisms and the measurement of bioaccumulation. (author)

  6. Simultaneous algae-polluted water treatment and electricity generation using a biocathode-coupled electrocoagulation cell (bio-ECC).

    Science.gov (United States)

    Dong, Yue; Qu, Youpeng; Li, Chao; Han, Xiaoyu; Ambuchi, John J; Liu, Junfeng; Yu, Yanling; Feng, Yujie

    2017-10-15

    How to utilize electrocoagulation (EC) technology for algae-polluted water treatment in an energy-efficient manner remains a critical challenge for its widespread application. Herein, a novel biocathode-coupled electrocoagulation cell (bio-ECC) with sacrificial iron anode and nitrifying biocathode was developed. Under different solution conductivities (2.33±0.25mScm -1 and 4.94±0.55mScm -1 ), the bio-ECC achieved almost complete removal of algae cells. The maximum power densities of 8.41 and 11.33Wm -3 at corresponding current densities of 48.03Am -3 and 66.26Am -3 were obtained, with the positive energy balance of 4.52 and 7.44Wm -3 . In addition, the bio-ECC exhibited excellent NH 4 + -N removal performance with the nitrogen removal rates of 7.28mgL -1 h -1 and 6.77mgL -1 h -1 in cathode chamber, indicating the superiority of bio-ECC in NH 4 + -N removal. Pyrosequencing revealed that nitrifiers including Nitrospira, Nitrobacter, Nitrosococcus, and Nitrosomonas were enriched in biocathode. The removal mechanisms of algae in anode chamber were also explored by AFM and SEM-EDX tests. These results provide a proof-of-concept study of transferring energy-intensive EC process into an energy-neutral process with high-efficiency algae removal and electricity recovery. Copyright © 2017. Published by Elsevier B.V.

  7. Algae from the arid southwestern United States: an annotated bibliography

    Energy Technology Data Exchange (ETDEWEB)

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

    1983-06-01

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

  8. Effects of Harmful Algae on the Physiology of Fishes

    DEFF Research Database (Denmark)

    Svendsen, Morten Bo Søndergaard

    Blooms of harmful planktonic algae causing adverse effects in aquatic environments are a global problem, causing both human morbidity and killing aquatic lifeforms worldwide. Focusing on fish kills, it is largely unknown what mechanisms of the fish’s physiology are affected during exposure......-waters having enough oxygen to sustain life, but not too warm like the surface water layer. The proposed adverse pathway, being gill destruction, for fish exposed to Alexandrium monilatum suggests that co-occurring events of Alexandrium monilatum and oxygen squeeze events will tighten the oxygen limitation...... is largely caused by the fish and to a lesser extent the experimental setup. Before this thesis, systematic studies of fish physiology under the influence of harmful algae consisted of one algae species, Chattonella marina. Now there are a total of 4 species studied. Lastly, during the Ph...

  9. Sex pheromone of marine algae; Kaiso no sei pheromone

    Energy Technology Data Exchange (ETDEWEB)

    Kajiwara, T. [Yamaguchi University, Yamaguchi (Japan). Faculty of Agriculture

    1997-10-20

    The marine ecosystem skillfully uses various `odor materials` as chemical signals. In particular, this `odor materials` are indispensable for various organisms with no motor function or poor underdeveloped visual sensation in order to maintain or expand their species. German algae scholars found a male gamete induction active material secreted from a female gamete of primitive brown algae in 1971. Eleven kinds of sex pheromones have been found from brown algae up to the present since 1971. All of these found sex pheromones are hydrophobic `odor materials` composed of hydrocarbons containing 8 or 11 carbon atoms or epoxide (oxirane), and are compounds with singular chemical structures as physiological active material in the hydrosphere. Some sex pheromones govern not only inducement of spermatozoons but also discharge of spermatozoons from an antheridium. The sex pheromone with both functions of discharge and inducement was found from the culture solution of a certain tangle weed. 2 refs., 2 figs.

  10. Characteristics of Red Algae Bioplastics/Latex Blends under Tension

    Directory of Open Access Journals (Sweden)

    M. Nizar Machmud

    2013-10-01

    Full Text Available Cassava, corn, sago and the other food crops have been commonly used as raw materials to produce green plastics. However, plastics produced from such crops cannot be tailored to fit a particular requirement due to their poor water resistance and mechanical properties. Nowadays, researchers are hence looking to get alternative raw materials from the other sustainable resources to produce plastics. Their recent published studies have reported that marine red algae, that has been already widely used as a raw material for producing biofuels, is one of the potential algae crops that can be turned into plastics. In this work, Eucheuma Cottonii, that is one of the red alga crops, was used as raw material to produce plastics by using a filtration technique. Selected latex of Artocarpus altilis and Calostropis gigantea was separately then blended with bioplastics derived from the red algae, to replace use of glycerol as plasticizer. Role of the glycerol and the selected latex on physical and mechanical properties of the red algae bioplastics obtained under a tensile test performed at room temperature are discussed. Tensile strength of some starch-based plastics collected from some recent references is also presented in this paperDoi: 10.12777/ijse.5.2.81-88 [How to cite this article: Machmud, M.N., Fahmi, R.,  Abdullah, R., and Kokarkin, C.  (2013. Characteristics of Red Algae Bioplastics/Latex Blends under Tension. International Journal of Science and Engineering, 5(2,81-88. Doi: 10.12777/ijse.5.2.81-88

  11. Using the marine unicellular algae in biological monitoring

    Directory of Open Access Journals (Sweden)

    Kapkov V. I.

    2017-06-01

    Full Text Available The possibility of using marine unicellular algae from natural plankton community in biomonitoring of pollution by heavy metals has been investigated. Algae of different taxa from the Mediterranean Sea have been allocated to culture. In the laboratory the culture conditions – i. e. growth medium, temperature, photoperiod, level of artificial light and initial density – have been selected for every species. The impact of heavy metals (Hg, Cd, Cu, Pb in the form of chloride salts on the growth of axenic algae culture has been studied in the modelling experiments. The unicellular marine algae have a very short life cycle, therefore it is possible to use them in the experiments of studying the effect of anthropogenic factors at cellular and population levels on the test-object. With biomonitoring pollution of marine environment by heavy metals and others dangerous toxicants, the major indicators of algae community condition are the cellular cycle and the condition of the photosynthetic apparatus of the cell. The subsequent lysis of cells under the influence of heavy metals leads to the excretion of secondary metabolites which can essentially affect the metal toxicity. The established scales of threshold and lethal concentration of heavy metals for algae of different taxon make it possible to use the ratio of sensitive and resistant species to heavy metals as biological markers when forecasting ecological consequences of pollution of the marine environment by heavy metals. Distinctions in the resistance of different taxon to heavy metals can result in implementing the strategy of selection of test-objects depending on the purposes of the research.

  12. Floating Algae Blooms in the East China Sea

    Science.gov (United States)

    Qi, Lin; Hu, Chuanmin; Wang, Mengqiu; Shang, Shaoling; Wilson, Cara

    2017-11-01

    A floating algae bloom in the East China Sea was observed in Moderate Resolution Imaging Spectroradiometer (MODIS) imagery in May 2017. Using satellite imagery from MODIS, Visible Infrared Imaging Radiometer Suite, Geostationary Ocean Color Imager, and Ocean Land Imager, and combined with numerical particle tracing experiments and laboratory experiments, we examined the history of this bloom as well as similar blooms in previous years and attempted to trace the bloom source and identify the algae type. Results suggest that one bloom origin is offshore Zhejiang coast where algae slicks have appeared in satellite imagery almost every February-March since 2012. Following the Kuroshio Current and Taiwan Warm Current, these "initial" algae slicks are first transported to the northeast to reach South Korea (Jeju Island) and Japan coastal waters (up to 135°E) by early April 2017, and then transported to the northwest to enter the Yellow Sea by the end of April. The transport pathway covers an area known to be rich in Sargassum horneri, and spectral analysis suggests that most of the algae slicks may contain large amount of S. horneri. The bloom covers a water area of 160,000 km2 with pure algae coverage of 530 km2, which exceeds the size of most Ulva blooms that occur every May-July in the Yellow Sea. While blooms of smaller size also occurred in previous years and especially in 2015, the 2017 bloom is hypothesized to be a result of record-high water temperature, increased light availability, and continuous expansion of Porphyra aquaculture along the East China Sea coast.

  13. Homogeneity of Danish environmental and clinical isolates of Shewanella algae

    DEFF Research Database (Denmark)

    Vogel, Birte Fonnesbech; Holt, H.M.; Gerner-Smidt, P.

    2000-01-01

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

  14. [Effects of aniline and phenol on freshwater algae growth].

    Science.gov (United States)

    Chen, Chuan-ping; Zhang, Ting-ting; He, Mei; Wu, An-ping; Nie, Liu-wang

    2007-01-01

    By the methods of bioassay, this paper studied the effects of aniline or phenol on the growth of Chlorella pyrenoidosa and Scenedesmus obiquus. The results showed that these two compounds had evident effects on the growth of test algae species. For the same species, aniline was more toxic. Under the same concentration of the compounds, S. obiquus was more sensitive than C. pyrenoidosa. These two algae species could degrade or absorb parts of the compounds, and phenol in particular, when their concentrations were lower.

  15. Chemical composition of the green alga Codium Divaricatum Holmes.

    Science.gov (United States)

    He, Zhizhou; Zhang, Anjiang; Ding, Lisheng; Lei, Xinxiang; Sun, Jianzhang; Zhang, Lixue

    2010-12-01

    A new sterol, 24-R-stigmasta-4,25-diene-3β,6β-diol (1), along with three known compounds (2-3), was isolated from the green alga Codium divaricatum Holmes, a traditional Chinese medicine, which is efficacious against cancer. All structures were determined by spectroscopic methods and comparison with related known compounds. Single-crystal X-ray crystallography allowed us to confirm the structure of 1. To our knowledge, the compound 1 is reported as the first from natural source, and compounds 2, 4 have not been isolated from green algae before. Copyright © 2010 Elsevier B.V. All rights reserved.

  16. The attached algae community near Pickering GS: III

    International Nuclear Information System (INIS)

    McKinley, S.R.

    1982-01-01

    The relationship between attached algae and macro-invertebrates in the nearshore zone of Lake Ontario was investigated in the vicinity of the Pickering 'A' NGS. Measures of faunal density, richness, evenness, and biomass were generally higher from areas which supported attached algae. Gammarus fasciatus, Cricotopus bicinctus, Dicrotendipes spp., Orthocladius obumbratus, Cladotanytarsus spp., Orthocladius spp., and Parakiefferiella spp., were significantly correlated with algal standing crop. All of the above dominant invertebrates ingested epiphytes associated with Cladophora glomerata. Attempts to explain the distribution of the zoobenthic assemblages using the physical/biological characteristics of the study area indicated algal cover, substrate size, wind velocity and water temperature were most important

  17. Hidden genetic diversity in the green alga Spirogyra (Zygnematophyceae, Streptophyta

    Directory of Open Access Journals (Sweden)

    Chen Charlotte

    2012-06-01

    Full Text Available Abstract Background The unbranched filamentous green alga Spirogyra (Streptophyta, Zygnemataceae is easily recognizable based on its vegetative morphology, which shows one to several spiral chloroplasts. This simple structure falsely points to a low genetic diversity: Spirogyra is commonly excluded from phylogenetic analyses because the genus is known as a long-branch taxon caused by a high evolutionary rate. Results We focused on this genetic diversity and sequenced 130 Spirogyra small subunit nuclear ribosomal DNA (SSU rDNA strands of different origin. The resulting SSU rDNA sequences were used for phylogenetic analyses using complex evolutionary models (posterior probability, maximum likelihood, neighbor joining, and maximum parsimony methods. The sequences were between 1672 and 1779 nucleotides long. Sequence comparisons revealed 53 individual clones, but our results still support monophyly of the genus. Our data set did not contain a single slow-evolving taxon that would have been placed on a shorter branch compared to the remaining sequences. Out of 130 accessions analyzed, 72 showed a secondary loss of the 1506 group I intron, which formed a long-branched group within the genus. The phylogenetic relationship to the genus Spirotaenia was not resolved satisfactorily. The genetic distance within the genus Spirogyra exceeded the distances measured within any other genus of the remaining Zygnemataceae included in this study. Conclusion Overall, we define eight distinct clades of Spirogyra, one of them including the genus Sirogonium. A large number of non-homoplasious synapomorphies (NHS; 114 NHS in total was found for Spirogyra (41 NHS and for each clade (totaling 73 NHS. This emphasizes the high genetic diversity of this genus and the distance to the remaining Zygnematophyceae.

  18. Distribution and biomass estimation of shell-boring algae in the intertidal area at Goa India

    Digital Repository Service at National Institute of Oceanography (India)

    Raghukumar, C.; Sharma, S.; Lande, V.

    and particulate organic carbon (POC) values in cultures of the green alga Gomontia sp. and the blue-green alga Plectonema terebrans, in biomass and POC contribution of these two types of microalgae in shells were calculated....

  19. Distribution of algae, seagrasses, and coral communities from Lakshadweep islands, eastern Arabian Sea

    Digital Repository Service at National Institute of Oceanography (India)

    Jagtap, T.G.

    Marine algae, seagrasses and coral from the intertidal, lagoon, reef and subtidal regions (up to 22 m depth) at Kavaratti, Agatti, Bangaram and Suheli islands, of Lakshadweep were studied Marine algae and seagrasses were mainly confined...

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

    Science.gov (United States)

    Meyer, C.

    1979-01-01

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

  1. Synthetic algae and cyanobacteria: Great potential but what is the exposure risk?

    Science.gov (United States)

    Green algae and cyanobacteria (hereafter, algae) have the attractive properties of relatively simple genomes, rapid growth rates, and an ability to synthesize useful compounds using solar energy and carbon dioxide. They are attractive targets for applications of synthetic biology...

  2. Pump apparatus including deconsolidator

    Energy Technology Data Exchange (ETDEWEB)

    Sonwane, Chandrashekhar; Saunders, Timothy; Fitzsimmons, Mark Andrew

    2014-10-07

    A pump apparatus includes a particulate pump that defines a passage that extends from an inlet to an outlet. A duct is in flow communication with the outlet. The duct includes a deconsolidator configured to fragment particle agglomerates received from the passage.

  3. Beberapa Marga Alga Benang dan Hubungannya dengan Keberadaan Vektor Malaria di Bali Utara

    OpenAIRE

    Seregeg, I. G

    1988-01-01

    A study of filamentous algae and its relation to malaria vector control was conducted during the dry season in several lagoons at the north coast of Bali. Floating masses of these algae under the sunshine barricated the spread of solar-triton larvicide, reducing tremendously the effectiveness of the larvicide. Identification of the genera of these algae under the subphyllum of CYANOPHYTA (Blue Algae) in the family of Cyanophyceae were Oscillatoria, Spirulina, Phormidium, Rivularia, Nostoc, an...

  4. Algae of economic importance that accumulate cadmium and lead: a review

    OpenAIRE

    Souza, Priscila O.; Ferreira, Lizângela R.; Pires, Natanael R. X.; S. Filho, Pedro J.; Duarte, Fabio A.; Pereira, Claudio M. P.; Mesko, Márcia F.

    2012-01-01

    Currently, algae and algae products are extensively applied in the pharmaceutical, cosmetic and food industries. Algae are the main organisms that take up and store heavy metals. Therefore, the use of compounds derived from algae by the pharmaceutical industry should be closely monitored for possible contamination. The pollution generated by heavy metals released by industrial and domestic sources causes serious changes in the aquatic ecosystem, resulting in a loss of biological diversity and...

  5. Developing New Alternative Energy in Virginia: Bio-Diesel from Algae

    Energy Technology Data Exchange (ETDEWEB)

    Hatcher, Patrick [Old Dominion University

    2012-03-29

    . The positive economics of this process are influenced by the following: 1. the weight percent of dry algae in suspension that can be fed into the evaporator, 2. the alga species’ ability to produce a higher yield of biodiesel, 3. the isolation of valuable methoxylated by-products, 4. recycling and regeneration of methanol and TMAH, and 5. the market value of biodiesel, commercial agricultural fertilizer, and the three methoxylated by-products. The negative economics of the process are the following: 1. the cost of producing dried, ground algae, 2. the capital cost of the equipment required for feedstock mixing, reaction, separation and recovery of products, and reactant recycling, and 3. the electrical cost and other utilities. In this report, the economic factors and results are assembled to predict the commercialization cost and its viability. This direct conversion process and equipment discussed herein can be adapted for various feedstocks including: other algal species, vegetable oil, jatropha oil, peanut oil, sunflower oil, and other TAG containing raw materials as a renewable energy resource.

  6. Evidence for widespread exonic small RNAs in the glaucophyte alga Cyanophora paradoxa.

    Directory of Open Access Journals (Sweden)

    Jeferson Gross

    Full Text Available RNAi (RNA interference relies on the production of small RNAs (sRNAs from double-stranded RNA and comprises a major pathway in eukaryotes to restrict the propagation of selfish genetic elements. Amplification of the initial RNAi signal by generation of multiple secondary sRNAs from a targeted mRNA is catalyzed by RNA-dependent RNA polymerases (RdRPs. This phenomenon is known as transitivity and is particularly important in plants to limit the spread of viruses. Here we describe, using a genome-wide approach, the distribution of sRNAs in the glaucophyte alga Cyanophora paradoxa. C. paradoxa is a member of the supergroup Plantae (also known as Archaeplastida that includes red algae, green algae, and plants. The ancient (>1 billion years ago split of glaucophytes within Plantae suggests that C. paradoxa may be a useful model to learn about the early evolution of RNAi in the supergroup that ultimately gave rise to plants. Using next-generation sequencing and bioinformatic analyses we find that sRNAs in C. paradoxa are preferentially associated with mRNAs, including a large number of transcripts that encode proteins arising from different functional categories. This pattern of exonic sRNAs appears to be a general trend that affects a large fraction of mRNAs in the cell. In several cases we observe that sRNAs have a bias for a specific strand of the mRNA, including many instances of antisense predominance. The genome of C. paradoxa encodes four sequences that are homologous to RdRPs in Arabidopsis thaliana. We discuss the possibility that exonic sRNAs in the glaucophyte may be secondarily derived from mRNAs by the action of RdRPs. If this hypothesis is confirmed, then transitivity may have had an ancient origin in Plantae.

  7. Optical modulator including grapene

    Science.gov (United States)

    Liu, Ming; Yin, Xiaobo; Zhang, Xiang

    2016-06-07

    The present invention provides for a one or more layer graphene optical modulator. In a first exemplary embodiment the optical modulator includes an optical waveguide, a nanoscale oxide spacer adjacent to a working region of the waveguide, and a monolayer graphene sheet adjacent to the spacer. In a second exemplary embodiment, the optical modulator includes at least one pair of active media, where the pair includes an oxide spacer, a first monolayer graphene sheet adjacent to a first side of the spacer, and a second monolayer graphene sheet adjacent to a second side of the spacer, and at least one optical waveguide adjacent to the pair.

  8. A review of the taxonomical and ecological studies on Netherlands’ Algae

    NARCIS (Netherlands)

    Koster, Joséphine Th.

    1939-01-01

    The earliest account of the Netherlands’ Algae appeared in 1781 in D. de Gorter, Flora VII Prov. Belgii foederati indigen. Here, however, in the Algae lichens and liverworts have been incorporated. The true Algae, of which 35 are enumerated, are principally marine, though also aërophytical and

  9. New methodologies for the integration of power plants with algae ponds

    NARCIS (Netherlands)

    Schipper, K.; Gijp, S. van der; Stel, R.W van der; Goetheer, E.L.V.

    2013-01-01

    It is generally recognized that algae could be an interesting option for reducing CO2 emissions. Based on light and CO2, algae can be used for the production various economically interesting products. Current algae cultivation techniques, however, still present a number of limitations. Efficient

  10. Abiotic Stress Tolerance of Charophyte Green Algae: New Challenges for Omics Techniques

    OpenAIRE

    Holzinger, Andreas; Pichrtov?, Martina

    2016-01-01

    Charophyte green algae are a paraphyletic group of freshwater and terrestrial green algae, comprising the classes of Chlorokybophyceae, Coleochaetophyceae, Klebsormidiophyceae, Zygnematophyceae, Mesostigmatophyceae, and Charo- phyceae. Zygnematophyceae (Conjugating green algae) are considered to be closest algal relatives to land plants (Embryophyta). Therefore, they are ideal model organisms for studying stress tolerance mechanisms connected with transition to land, one of the most important...

  11. The toxicity of plastic nanoparticles to green algae as influenced by surface modification, medium hardness and cellular adsorption.

    Science.gov (United States)

    Nolte, Tom M; Hartmann, Nanna B; Kleijn, J Mieke; Garnæs, Jørgen; van de Meent, Dik; Jan Hendriks, A; Baun, Anders

    2017-02-01

    To investigate processes possibly underlying accumulation and ecological effects of plastic nano-particles we have characterized their interaction with the cell wall of green algae. More specifically, we have investigated the influence of particle surface functionality and water hardness (Ca 2+ concentration) on particle adsorption to algae cell walls. Polystyrene nanoparticles with different functional groups (non-functionalized, -COOH and -NH 2 ) as well as coated (starch and PEG) gold nanoparticles were applied in these studies. Depletion measurements and atomic force microscopy (AFM) showed that adsorption of neutral and positively charged plastic nanoparticles onto the cell wall of P. subcapitata was stronger than that of negatively charged plastic particles. Results indicated that binding affinity is a function of both inter-particle and particle-cell wall interactions which are in turn influenced by the medium hardness and particle concentration. Physicochemical modelling using DLVO theory was used to interpret the experimental data, using also values for interfacial surface free energies. Our study shows that material properties and medium conditions play a crucial role in the rate and state of nanoparticle bio-adsorption for green algae. The results show that the toxicity of nanoparticles can be better described and assessed by using appropriate dose metrics including material properties, complexation/agglomeration behavior and cellular attachment and adsorption. The applied methodology provides an efficient and feasible approach for evaluating potential accumulation and hazardous effects of nanoparticles to algae caused by particle interactions with the algae cell walls. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Conventional and Unconventional Antimicrobials from Fish, Marine Invertebrates and Micro-algae

    Directory of Open Access Journals (Sweden)

    Valerie J. Smith

    2010-04-01

    Full Text Available All eukaryotic organisms, single-celled or multi-cellular, produce a diverse array of natural anti-infective agents that, in addition to conventional antimicrobial peptides, also include proteins and other molecules often not regarded as part of the innate defences. Examples range from histones, fatty acids, and other structural components of cells to pigments and regulatory proteins. These probably represent very ancient defence factors that have been re-used in new ways during evolution. This review discusses the nature, biological role in host protection and potential biotechnological uses of some of these compounds, focusing on those from fish, marine invertebrates and marine micro-algae.

  13. Dereplication and Chemotaxonomical Studies of Marine Algae of the Ochrophyta and Rhodophyta Phyla

    Directory of Open Access Journals (Sweden)

    Robert Brkljača

    2015-04-01

    Full Text Available Dereplication and chemotaxonomic studies of six marine algae of the Ochrophyta and one of the Rhodophyta phyla resulted in the detection of 22 separate compounds. All 16 secondary metabolites, including four new compounds (16–19, could be rapidly dereplicated using HPLC-NMR and HPLC-MS methodologies in conjunction with the MarinLit database. This study highlights the advantages of using NMR data (acquired via HPLC-NMR for database searching and for the overall dereplication of natural products.

  14. A method for the extraction and quantitation of phycoerythrin from algae

    Science.gov (United States)

    Stewart, D. E.

    1982-01-01

    A summary of a new technique for the extraction and quantitation of phycoerythrin (PHE) from algal samples is described. Results of analysis of four extracts representing three PHE types from algae including cryptomonad and cyanophyte types are presented. The method of extraction and an equation for quantitation are given. A graph showing the relationship of concentration and fluorescence units that may be used with samples fluorescing around 575-580 nm (probably dominated by cryptophytes in estuarine waters) and 560 nm (dominated by cyanophytes characteristics of the open ocean) is provided.

  15. Conventional and Unconventional Antimicrobials from Fish, Marine Invertebrates and Micro-algae

    Science.gov (United States)

    Smith, Valerie J.; Desbois, Andrew P.; Dyrynda, Elisabeth A.

    2010-01-01

    All eukaryotic organisms, single-celled or multi-cellular, produce a diverse array of natural anti-infective agents that, in addition to conventional antimicrobial peptides, also include proteins and other molecules often not regarded as part of the innate defences. Examples range from histones, fatty acids, and other structural components of cells to pigments and regulatory proteins. These probably represent very ancient defence factors that have been re-used in new ways during evolution. This review discusses the nature, biological role in host protection and potential biotechnological uses of some of these compounds, focusing on those from fish, marine invertebrates and marine micro-algae. PMID:20479976

  16. New additions of coccoid green algae to the phycoflora of Brazil and the Neotropics

    Directory of Open Access Journals (Sweden)

    Geraldo José Peixoto Ramos

    2014-03-01

    Full Text Available The present study presents 11 new additions of coccoid green algae to the phycoflora of Brazil, including the first record of the genus Westellopsis for the neotropical region. Samples of periphyton and plankton were collected in two areas of the Marimbus Wetlands (the Marimbus do Baiano and Marimbus do Remanso, within the Marimbus-Iraquara Environmentally Protected Area, in the Chapada Diamantina Region of the state of Bahia, Brazil. Sample collection occurred during dry periods (April-June and August 2011 and rainy periods (October-December 2011 and February 2012. Here, we describe the taxa identified from the 56 samples collected.

  17. Sexual reproduction and sex determination in green algae.

    Science.gov (United States)

    Sekimoto, Hiroyuki

    2017-05-01

    The sexual reproductive processes of some representative freshwater green algae are reviewed. Chlamydomonas reinhardtii is a unicellular volvocine alga having two mating types: mating type plus (mt + ) and mating type minus (mt - ), which are controlled by a single, complex mating-type locus. Sexual adhesion between the gametes is mediated by sex-specific agglutinin molecules on their flagellar membranes. Cell fusion is initiated by an adhesive interaction between the mt + and mt - mating structures, followed by localized membrane fusion. The loci of sex-limited genes and the conformation of sex-determining regions have been rearranged during the evolution of volvocine algae; however, the essential function of the sex-determining genes of the isogamous unicellular Chlamydomonas reinhardtii is conserved in the multicellular oogamous Volvox carteri. The sexual reproduction of the unicellular charophycean alga, Closterium peracerosum-strigosum-littorale complex, is also focused on here. The sexual reproductive processes of heterothallic strains are controlled by two multifunctional sex pheromones, PR-IP and PR-IP Inducer, which independently promote multiple steps in conjugation at the appropriate times through different induction mechanisms. The molecules involved in sexual reproduction and sex determination have also been characterized.

  18. On the pigment system of the red alga Porphyra Lacineata

    NARCIS (Netherlands)

    Thomas, J.B.; Marsman, J.W.

    1959-01-01

    Absorption and fluorescence around 725 mμ of suspensions of the red alga Porphyra lacineata were studied both with and without the phycobilins attached to the pigment system. The in vivo occurrence of 2 chlorophyll a types was confirmed spectroscopically. Their red absorption maxima are located at

  19. Algas vene kirjanduse nädal / Raimu Hanson

    Index Scriptorium Estoniae

    Hanson, Raimu, 1957-

    2008-01-01

    22. septembril algas Tartu Linnaraamatukogus vene kirjanduse nädal Inga Ivanova raamatu "Kadunud koerte saladus" esitlusega; 24. sept. toimub Igor Kotjuhi autoriõhtu; 26.-28. toimub Tartu Ülikoolis vene kirjandusele pühendatud rahvusvaheline teaduskonverents. Raamatukogust saab osta ka venekeelseid raamatuid

  20. Diversity of the Symbiotic Alga Symbiodinium in Tanzanian ...

    African Journals Online (AJOL)

    Abstract—With the current increase in frequency of coral bleaching events, knowledge on the genetic diversity of symbiotic algae in the genus Symbiodinium harboured by reef-building corals is important to understand how coral reefs will respond to global climate change. This study was undertaken as very little is known.