WorldWideScience

Sample records for blue-green algae cyanobacteria

  1. Blue-Green Algae

    Science.gov (United States)

    ... that taking a specific blue-green algae product (Super Blue-Green Algae, Cell Tech, Klamath Falls, OR) ... system. Premenstrual syndrome (PMS). Depression. Digestion. Heart disease. Memory. Wound healing. Other conditions. More evidence is needed ...

  2. Isolation and Molecular Identification of Some Blue-Green Algae (Cyanobacteria from Freshwater Sites in Tokat Province of Turkey

    Directory of Open Access Journals (Sweden)

    Tunay Karan

    2017-11-01

    Full Text Available Collected blue-green algae (cyanobacteria from freshwater sites throughout Tokat province and its outlying areas were isolated in laboratory environment and their morphological systematics were determined and also their species identifications were studied by molecular methods. Seven different species of blue-green algae collected from seven different sites were isolated by purifying in cultures in laboratory environment. DNA extractions were made from isolated cells and extracted DNAs were amplified by using PCR. Cyanobacteria specific primers were used to amplify 16S rRNA and phycocyanine gene regions using PCR. Phylogenetic identification of species were conducted by evaluation of obtained sequence analysis data by using computer software. According to species identification by sequence analysis, it was seen that molecular data supports morphological systematics.

  3. 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.

  4. 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.)

  5. EFFECT OF BLUE GREEN ALGAE ON SOIL NITROGEN

    African Journals Online (AJOL)

    Yagya Prasad Paudel

    2012-07-31

    Jul 31, 2012 ... associated with soil dessication at the end of the cultivation cycle and algal growth ... blue-green algae (BGA) on soil nitrogen was carried out from June to December 2005. .... Nitrogen fixation by free living Micro-organisms.

  6. 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...

  7. Extraction of Nutraceuticals from Spirulina (Blue-Green Alga): A Bioorganic Chemistry Practice Using Thin-layer Chromatography

    Science.gov (United States)

    Herrera Bravo de Laguna, Irma; Toledo Marante, Francisco J.; Luna-Freire, Kristerson R.; Mioso, Roberto

    2015-01-01

    Spirulina is a blue-green alga (cyanobacteria) with high nutritive value. This work provides an innovative and original approach to the consideration of a bioorganic chemistry practice, using Spirulina for the separation of phytochemicals with nutraceutical characteristics via thin-layer chromatography (TLC) plates. The aim is to bring together…

  8. 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

  9. Origin and evolution of osmoregulatory mechanisms in blue-green algae (cyanobacteria) as a function of metabolic and structural complexity: Reflections of Precambrian paleobiology

    Science.gov (United States)

    Yopp, John H.; Tindall, Donald R.; Pavlicek, Kenneth

    1987-01-01

    Major accomplishments underlying the basic understanding of cyanobacterial resistance to salt tolerance and osmotic stress were made. The methodology proposed included: the tracing of the pathways of formation of osmoregulatory solutes by traditional methods involving C-14 labelled substrates; gas chromatography; amino acid analysis; X-ray analysis using scanning transmission electron microscopy; and most importantly, C-13 labelled substrates, followed by Nuclear Magnetic Resonance (NMR) spectroscopy. It was found that the cyanobacteria employ a diversity of organic, osmoregulatory solutes. Osmoregulatory solutes were found to serve four functions: adjustment of water activity, noninhibition of enzymes; lowering of K sub m of enzymes to allow functioning at normal levels when the intracellular salt accumulates, and extending the pH optimum of enzymes as intracellular pH rises due to proton-potassium ion pump action during osmoregulation. Differences in osmoregulatory solutes may, but are not always, be attributed to differences in nutritional capabilities. The mechanism of osmoregulation and concomitant salt tolerance in halophilic cyanobacteria was elucidated. The activities of betaine and S-Adenosylhomocysteine hydrolase are discussed.

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

    International Nuclear Information System (INIS)

    Thomas, J.

    1978-01-01

    Fluorescence emission spectra at 77K of isolated heterocysts of Anabaena L-31 do not show F685-695 but rather F715-730, thus confirming the absence of photosystem II and the presence of photosystem I. Recent work using radioactive nitrogen has been collated and a tentative scheme is outlined indicating the location of the enzymes and the pathways involved in the initial assimilation of nitrogen in blue-green algae. Glutamine synthetase extracted from heterocysts of Anabaena L-31 does not exhibit the adenylylation/deadenylylation phenomenon characteristic of the enzyme from bacteria. Our recent experiments suggest that nitrogenase in Anabaena is under dual control by glutamic acid and aspartic acid, the former inhibiting the enzyme synthesis and the latter relieving the inhibition. Two extracellular polypeptides have been obtained from this alga, one of which inhibits heterocyst formation whereas the other enhances heterocyst formation and partially relieves the inhibitory effect of the former. An extracellular substance, possibly a glycopeptide, has been obtained from A. torulosa, which stimulates sporulation. Studies with 24 Na and 22 Na indicate that A. torulosa, an alga from saline habitats, has an active photosynthesis-linked mechanism for the extrusion of sodium. Sodium is essential for optimum nitrogenase activity and growth. In field experiments inoculation with Nostoc 4 resulted in substantial increase in soil nitrogen. Paddy yield was comparable to those plots where 80kg N/ha of urea was used. (author)

  11. Bioelectricity generation and microcystins removal in a blue-green algae powered microbial fuel cell

    International Nuclear Information System (INIS)

    Yuan Yong; Chen Qing; Zhou Shungui; Zhuang Li; Hu Pei

    2011-01-01

    Bioelectricity production from blue-green algae was examined in a single chamber tubular microbial fuel cell (MFC). The blue-green algae powered MFC produced a maximum power density of 114 mW/m 2 at a current density of 0.55 mA/m 2 . Coupled with the bioenergy generation, high removal efficiencies of chemical oxygen demand (COD) and nitrogen were also achieved in MFCs. Over 78.9% of total chemical oxygen demand (TCOD), 80.0% of soluble chemical oxygen demand (SCOD), 91.0% of total nitrogen (total-N) and 96.8% ammonium-nitrogen (NH 3 -N) were removed under closed circuit conditions in 12 days, which were much more effective than those under open circuit and anaerobic reactor conditions. Most importantly, the MFC showed great ability to remove microcystins released from blue-green algae. Over 90.7% of MC-RR and 91.1% of MC-LR were removed under closed circuit conditions (500 Ω). This study showed that the MFC could provide a potential means for electricity production from blue-green algae coupling algae toxins removal.

  12. Modeling the Role of Zebra Mussels in the Proliferation of Blue-green Algae in Saginaw Bay, Lake Huron

    Science.gov (United States)

    Under model assumptions from Saginaw Bay 1991, selective rejection of blue-green algae by zebra mussels appears to be a necessary factor in the enhancement of blue-green algae production in the presence of zebra mussels. Enhancement also appears to depend on the increased sedime...

  13. Characterization of blue green algae isolated from Egyptian rice ...

    African Journals Online (AJOL)

    Several species of cyanobacteria has been recognized for its therapeutic value that can be used for treatment of malnutrition, cancer and viral infection. Many natural occurring cyanobacteria are known to produce toxins, for example, species of the genera Microcystis, Nodularia, Nostoc, Anabaena, Aphanizomenon, ...

  14. Some metabolic pathways in the blue - green alga micro cystis aeruginosa using 14 C - Labelled compounds

    International Nuclear Information System (INIS)

    Mohammed, H.A.K.

    1993-01-01

    Blue - green algae (cyanobacteria) are of world Wied distribution in fresh water, their toxic and nontoxic strains are forming heavy blooms regularly in eutrophic natural water. They grow rapidly under many physicochemical stresses even in many domestic sewage (Skulberg et al., 1984). The toxic and nontoxic strains are morphologically indistin - guishable, so extensive toxicity testing must be taken into consideration and is so much essential because some species are marketed to human consumption as a food. From the toxicological point of view, at least five genera are now known as toxic strains, these are anabaena, nostoc, oscillator, aphanizomenon, micro cystis (Carmichael, 1981; Carmichael and Mahmood, 1984, and carmichael et al, 1985). The toxicity levels of these species are varied widely with regard to site, season, week or even day of collection (Carmichael and Gorham, 1981). Such variability may be correlated to the changes in species composition. The intensive growth of toxin producing organisms in municipal and recreational water supplies affect human health both wild and domestic animals, Livestock, pets, fish and birds in many countries and are suspected to cause the last and smell of drinking water to be unpleasant (Beasley et al, 1983 and carmichael et al, 1985)

  15. Effect of blue-green algae on soil nitrogen | Paudel | African Journal ...

    African Journals Online (AJOL)

    Effect of blue-green algae on soil nitrogen. ... African Journal of Biotechnology ... In paddy fields, the death of algal biomass is most frequently associated with soil dessication at the end of the cultivation cycle and algal growth has frequently resulted in a gradual build up of soil fertility with a residual effect on succeeding crop ...

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

    African Journals Online (AJOL)

    meldemellawy

    2014-02-20

    Feb 20, 2014 ... cyanobacteria, where CV-N blocks HIV infection by binding to the .... chain reaction (RT-PCR) has become the most frequently-used, ..... Microbial ecology. 51(2):154-165. Rao PV, Gupta N, Bhaskar AS, Jayaraj R (2002).

  17. Pathophysiology and Toxicokinetic Studies of Blue-Green Algae Intoxication in the Swine Model

    Science.gov (United States)

    1991-06-26

    Carmichael, W. W., Kleppe, G., Hooser, S. B., and Haschek, W. M. (1987) Blue-grezn algae (Microcystis aeruginosa) hepatotoxicosis in dairy cows . Am. J. Vet...Kleppe, G., Hooser, S. B., and Haschek, W. M. (1987) Blue-green algae (Microcystis aeruginosa) hepatotoxicosis in dairy cows . Am. J. Vet. Res. 48...containing (per 500 ml) 100 ml of fetal bovine serum (FBS) and 0.3 ml of insulin (100 U/ml), and placed on ice. Uptake of Dihydromicrocystin-LR into

  18. Effects of antibiotics and ultraviolet radiation on the halophilic blue-green alga

    International Nuclear Information System (INIS)

    Yopp, J.H.; Albright, G.; Miller, D.M.; Southern Illinois Univ., Carbondale

    1979-01-01

    The effects of a variety of antibiotics, ultraviolet radiation and N-methyl-N-nitro-N-nitro-N-nitrosoguanidine (NTG) on the survival and mutability of the halophilic blue-green alga, Aphanothece halophytica, were determined. The halophile was found extremely sensitive to penicillin G and bacitracin; moderately sensitive to novobiocin, amino acid analogs, chloramphenicol and streptomycin; and tolerant to actidione and hydroxyurea. Ultraviolet and NTG killing curves and photoreactivation capabilities were seimilar to those reported for other members of the Chroococcales. Three stable morphological mutants were obtained by ultraviolet and NTG treatment, the latter being much more efficient in the production of mutants. (orig.)

  19. Neutron activation analysis for development of mercury sorbent based on blue-green alga salipriina palatinates

    International Nuclear Information System (INIS)

    Frontasyeva, M.V.; Kirkesali, E.I.; Aksenova, N.G.; Mosulishvili, L.M.; Belokobylsky, A.I.; Khizanishvili, A.I.

    2005-01-01

    Epithermal neutron activation analysis was used to study interaction of blue-green alga Spirulina platensis with toxic metal mercury. Various concentrations of Hg(II) were added to cell cultures in a nutrient medium. The dynamic of accumulation of Hg was investigated over days in relation to Spirulina biomass growth. The process of Hg adsorption by Spirulina biomass was studied in short-time experiments. The isotherm of adsorption was / out in Freindlich coordinates. Natural Spirulina biomass has potential to be used in the remediation of sewage waters at Hg concentrations ∼ 100 μg/1

  20. Blue green alga mediated synthesis of gold nanoparticles and its antibacterial efficacy against Gram positive organisms

    Energy Technology Data Exchange (ETDEWEB)

    Uma Suganya, K.S. [Centre for Ocean Research, Sathyabama University, Chennai 600 119 (India); Govindaraju, K., E-mail: govindtu@gmail.com [Centre for Ocean Research, Sathyabama University, Chennai 600 119 (India); Ganesh Kumar, V.; Stalin Dhas, T.; Karthick, V. [Centre for Ocean Research, Sathyabama University, Chennai 600 119 (India); Singaravelu, G. [Nanoscience Division, Department of Zoology, Thiruvalluvar University, Vellore 632115 (India); Elanchezhiyan, M. [Department of Microbiology, Dr ALM Post Graduate Institute of Basic Medical Sciences, University of Madras, Chennai 600113 (India)

    2015-02-01

    Biofunctionalized gold nanoparticles (AuNPs) play an important role in design and development of nanomedicine. Synthesis of AuNPs from biogenic materials is environmentally benign and possesses high bacterial inhibition and bactericidal properties. In the present study, blue green alga Spirulina platensis protein mediated synthesis of AuNPs and its antibacterial activity against Gram positive bacteria is discussed. AuNPs were characterized using Ultraviolet–visible (UV–vis) spectroscopy, Fluorescence spectroscopy, Fourier Transform-Infrared (FTIR) spectroscopy, Raman spectroscopy, High Resolution-Transmission Electron Microscopy (HR-TEM) and Energy Dispersive X-ray analysis (EDAX). Stable, well defined AuNPs of smaller and uniform shape with an average size of ∼ 5 nm were obtained. The antibacterial efficacy of protein functionalized AuNPs were tested against Gram positive organisms Bacillus subtilis and Staphylococcus aureus. - Highlights: • Size controlled synthesis of gold nanoparticles from blue green alga Spirulina platensis • Stability of gold nanoparticles at different temperatures • Potent antibacterial efficacy against Gram positive organisms.

  1. Photoreactivation of UV-irradiated blue-green algae and algal virus LPP-1

    Energy Technology Data Exchange (ETDEWEB)

    Singh, P K [Central Rice Research Inst., Cuttack (India)

    1975-01-01

    Ultraviolet (UV) sensitivity and photoreactivation of blue-green algae Cylindrospermum sp., Plectonema boryanum, spores of Fischerella muscicola and algal virus (cyanophage) LPP-1 were studied. The survival value after UV irradiation of filaments of Cylindrospermum sp. and Virus LPP-1 showed exponential trend and these were comparatively sensitive towards UV than F. muscicola and P. boryanum. Photoreactivation of UV-induced damage occurred in black, blue, green, yellow, red and white light in Cylindrospermum sp., however only black, blue and white light were capable of photorepair of UV-induced damage in P. boryanum, spores of F. muscicola and virus LPP-1 in infected host alga. Pre-exposure to yellow and black light did not show photoprotection. The non-heterocystous and nitrogen fixation-less mutants of Cylindrospermum sp. were not induced by UV and their spontaneous mutation frequency was not affected after photoreactivation. The short trichome mutants of P. boryanum were more resistant towards UV. The occurrence of photoreactivation of UV-induced killing in wide range of light in Cylindrospermum sp. is the first report in organisms.

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

    Science.gov (United States)

    1985-10-01

    These toxins have caused loss of cattle and wild animals, due to the consumption of the contami- nated water and the bloom mass, in several countries...of American Association of Anatomists, Miami, 1979. Koenig, H. and Dabholkar, A.S.: Rapid effects of testosterone, pilocarpine and castration in rat

  3. Moessbauer study of cobalt and iron in the cyanobacterium (blue green alga)

    International Nuclear Information System (INIS)

    Ambe, Shizuko

    1990-01-01

    Moessbauer emission and absorption studies have been performed on cobalt and iron in the cyanobacterium (blue-green alga). The Moessbauer spectrum of the cyanobacterium cultivated with 57 Co is decomposed into two doublets. The parameters of the major doublet are in good agreement with those of cyanocobalamin (vitamin B 12 ) labeled with 57 Co. The other minor doublet has parameters close to those of Fe(II) coordinated with six nitrogen atoms. These suggest that cobalt is used for the biosynthesis of vitamin B 12 or its analogs in the cyanobacterium. The spectra of the cyanobacterium grown with 57 Fe show that iron is in the high-spin trivalent state and possibly in the form of ferritin, iron storage protein. (orig.)

  4. Hydrogen evolution by a thermophilic blue-green alga. Mastigocladus laminosus

    Energy Technology Data Exchange (ETDEWEB)

    Mirua, Y; Yokoyama, H; Kanaoka, K; Saito, S; Iwasa, K; Okazaki, M; Komemushi, S

    1980-01-01

    The thermophillic blue-green alga (cyanobacterium), Mastigocladus laminosus isolated from a hot spring, evolved hydrogen gas under nitrogen-starved conditions in light when algal cells were grown in a nitrate-free medium. Cells grown in a nitrate-medium evolved no detectable hydrogen gas in light. The optimal temperature and pH for hydrogen evolution were 44-49 degrees C and 7.0-7.5. High activity of hydrogen evolution, 1.6 ml H/sub 2//mg chl.hr, was induced when algal cells grown in the nitrate medium were actively forming heterocysts in the nitrate-free medium in air. Hydrogen evolution in light was depressed by nitrogen gas and inhibited by salicylaldoxime or DNP. This hydrogen evolution by M. laminosus is attributed to the action of nitrogenase.

  5. Energy transfer from carotenoids to chlorophyll in blue-green, red and green algae and greening bean leaves

    NARCIS (Netherlands)

    Goedheer, J.C.

    1969-01-01

    From fluorescence action spectra, fluorescence spectra and absorption spectra measured at room temperature and at 77 °K of light petroleum (b.p. 40–60°)-treated and normal chloroplasts, it is concluded that: 1. 1. In blue-green and red algae energy transfer from β-carotene to chlorophyll occurs

  6. Indicators: Cyanobacteria

    Science.gov (United States)

    Cyanobacteria, also referred to as blue-green algae, naturally occur in all freshwater ecosystems. However, too many nutrients such as phosphorus and nitrogen in the waterway can result in conditions that lead to cyanobacterial blooms.

  7. Synthesis of gold nanoparticles by blue-green algae Spirulina platensis

    International Nuclear Information System (INIS)

    Kalabegishvili, T.; Kirkesali, E.; Rcheulishvili, A.

    2012-01-01

    The synthesis of gold nanoparticles by one of the many popular microorganisms - blue-green algae Spirulina platensis was studied. The complex of optical and analytical methods was applied for investigation of experimental samples after exposure to chloroaurate (HAuCl 4 ) solution at different doses and for different time intervals. To characterize formed gold nanoparticles UV-vis, TEM, SEM, EDAX, and XRD were used. It was shown that after 1.5-2 days of exposure the extracellular formation of nanoparticles of spherical form and the distribution peak within the interval of 20-30 nm took place. To determine gold concentrations in the Spirulina platensis biomass, neutron activation analysis (NAA) and atomic absorption spectrometry (AAS) were applied. The results obtained evidence that the concentration of gold accumulated by Spirulina biomass is rapidly growing in the beginning, followed by some increase for the next few days. The obtained substance of Spirulina biomass with gold nanoparticles may be used for medical, pharmaceutical, and technological purposes

  8. Effect of inoculating blue-green algae and Azolla on rice yield

    International Nuclear Information System (INIS)

    Kulasooriya, S.A.

    1985-01-01

    Nitrogen fixing blue-green algae (BGA) and the Azolla-Anaebaena symbiosis are potential alternative sources of nitrogen for lowland rice production. A survey of the literature shows that on the average, when BGA inoculation is effective, a rice yield increase of 14% (450 kg grain ha -1 ) has been observed. However, in Sri Lanka no significant increases in grain yield have been observed due to BGA inoculation. Azolla inoculation in broadcast, transplanted, and avenue transplanted rice gave yield increases of 12, 22 and 48%, and was equivalent to 55 to 80 kg N ha -1 as urea. Azolla was observed to reduce weed growth by 53%. Azolla is easier to establish in rice fields since it can be easily recognized with the naked eye, however, BGA are better able to withstand periods of desiccation which occur in rain-fed rice production. Most algalization experiments have been performed on a ''black box'' basis where only the final grain yield has been measured. Isotope experiments can play a vital role in understanding the processes by which BGA and Azolla increase rice yields. (author)

  9. The hepatoprotective activity of blue green algae in Schistosoma mansoni infected mice.

    Science.gov (United States)

    Mohamed, Azza H; Osman, Gamalat Y; Salem, Tarek A; Elmalawany, Alshimaa M

    2014-10-01

    This study aims to evaluate the immunomodulatory effects of a natural product, blue green algae (BGA) (100 mg/kg BW), alone or combined with praziquantel PZQ (250 mg/kg BW) on granulomatous inflammation, liver histopathology, some biochemical and immunological parameters in mice infected with Schistosoma mansoni. Results showed that the diameter and number of egg granuloma were significantly reduced after treatment of S. mansoni-infected mice with BGA, PZQ and their combination. The histopathological alterations observed in the liver of S. mansoni-infected mice were remarkably inhibited after BGA treatments. BGA decreased the activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP) as well as the level of total protein (TP) while the level of albumin was increased. Treatment of infected mice with BGA, PZQ as well as their combination led to significant elevation in the activities of hepatic antioxidant enzymes glutathione peroxidase (GPX) and glutathione-S-transferase (GST) as compared with control group. Combination of BGA and PZQ resulted in significant reduction in the level of intercellular adhesion molecules-1 (ICAM-1), vascular adhesion molecules-1 (VCAM-1) and tumor necrosis factor-alpha (TNF-α) when compared to those of the S. mansoni-infected group. Overall, BGA significantly inhibited the liver damage accompanied with schistosomiasis, exhibited a potent antioxidant and immunoprotective activities. This study suggests that BGA can be considered as promising for development a complementary and/or alternative medicine against schistosomiasis. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Experimental grounds for developing selenium- and iodine-containing pharmaceuticals based on blue-green algae Spirulina platensis

    International Nuclear Information System (INIS)

    Frontas'eva, M.V.; Pavlov, S.S.; Mosulishvili, L.M.; Belokobyl'skij, A.I.; Kirkesali, E.I.

    2002-01-01

    The possibility of using blue-green algae Spirulina platensis as a matrix for production of the selenium- and iodine-containing pharmaceuticals was studied. The dependence of Se and I accumulation in Spirulina biomass during the cultivation in a nutrient medium loading of above elements was determined more precisely. The dynamics of Spirulina biomass growth was observed with nutrient medium loading of selenium. It is found that Spirulina platensis biomass quality may be used for pharmaceutical purposes

  11. X-ray induced inactivation of the capacity for photosynthetic oxygen evolution and nitrate reduction in blue-green algae

    International Nuclear Information System (INIS)

    Stevens, S.E. Jr.; Simic, M.G.; Rao, V.S.K.

    1975-01-01

    The level of inactivation of oxygen evolving photosynthesis in the green alga, Chlorella pyrenoidosa was 12 percent in N 2 at a dose of 100 krad of x irradiation. Under similar conditions, as well as under O 2 , there resulted a 20 percent inactivation of the same function in the blue-green algae, Agmenellum quadruplicatum, strains PR-6 and AQ-6. Nitrate reduction capacity in the mutant AQ-6 was inactivated to 40 percent in N 2 and to 7 percent in O 2 . Catalase and formate provided some protection from irradiation in O 2 , suggesting some inactivation by H 2 O 2 . Most of the damage to the nitrate reduction system resulted from the direct action of x irradiation on a constitutive subunit of the nitrate reductase complex. Moreover, the slight inactivation of the O 2 evolving system, a function which is associated with photosystem II, cannot account for the inactivation of nitrate reduction

  12. Epithermal neutron activation analysis of blue-green algae Spirulina Platensis as a matrix for selenium-containing pharmaceuticals

    International Nuclear Information System (INIS)

    Mosulishvili, L.M.; Kirkesali, E.I.; Belokobyl'skij, A.I.; Khizanishvili, A.I.; Frontas'eva, M.V.; Gundorina, S.F.; Oprea, C.D.

    2000-01-01

    To evaluate the potentiality of the blue-green algae Spirulina Platensis as a matrix for the production of Se-containing pharmaceuticals, the background levels of 31 major, minor and trace elements (Na, Mg, Al, Cl, K, Ca, Sc, V, Cr, Mn, Fe, Co, Ni (using (n,p)-reaction), As, Br, Zn, Rb, Mo, Ag, Sb, I, Ba, Sm, Tb, Tm, Hf, Ta, W, Au, Hg, Th) in Spirulina Platensis biomass were determined by means of epithermal neutron activation analysis. The possibility of the purpose-oriented incorporation of Se into Spirulina Platensis biomass was demonstrated. The polynomial dependence of the Se accumulation on nutritional medium loading was revealed. The employed analytical technique allows one to reliably control the amount of toxic elements in algae Spirulina Platensis. Based on this study, a conclusion of the possibility to use Spirulina Platensis as a matrix for the production of Se-containing pharmaceuticals was drawn

  13. Growth of filamentous blue-green algae at high temperatures: a source of biomass for renewable fuels

    Energy Technology Data Exchange (ETDEWEB)

    Timourian, H.; Ward, R.L.; Jeffries, T.W.

    1977-08-17

    The growth of filamentous blue-green algae (FBGA) at high temperatures in outdoor, shallow solar ponds is being investigated. The temperature of the 60-m/sup 2/ ponds can be controlled to an average temperature of 45/sup 0/C. The growth of FBGA at high temperatures offers an opportunity, not presently available from outdoor algal ponds or energy farms, to obtain large amounts of biomass. Growth of algae at high temperatures results in higher yields because of increased growth rate, the higher light intensity that can be used before saturating the photosynthetic process, easier maintenance of selected FBGA strains, and fewer predators to decimate culture. Additional advantages of growing FBGA as a source of biomass include: bypassing the limitations of nutrient sources, because FBGA fix their own nitrogen and require only CO/sub 2/ when inorganic nutrients are recycled; toleration of higher salinity and metal ion concentrations; and easier and less expensive harvesting procedures.

  14. Evidence for dark repair of far ultraviolet light damage in the blue-green alga, Gloeocapsa alpicola

    International Nuclear Information System (INIS)

    Williams, E.; Lambert, J.; O'Brien, P.; Houghton, J.A.

    1979-01-01

    The inactivating effect of far UV light on the unicellular blue-green alga Gloeocapsa alpicola could be totally reversed by exposure to blue light immediately after irradiation. However, if the irradiated cells were held in the dark before exposure to blue light, reversal became progressively less efficient, and almost disappeared after 60-80 h holding. Caffeine and acriflavine inhibited loss of photoreversibility, suggesting an involvement of excision functions. Chloramphenicol and rifampicin slightly increased the rate of loss of photoreversibility, indicating that inducible functions play only a minor role. Split UV dose experiments indicated that light-dependent repair remained operational during dark liquid holding. These results provide preliminary evidence for dark repair in G. alpicola. (author)

  15. Contamination by Microcystis and microcystins of blue-green algae food supplements (BGAS) on the Italian market and possible risk for the exposed population.

    Science.gov (United States)

    Vichi, Susanna; Lavorini, Paolo; Funari, Enzo; Scardala, Simona; Testai, Emanuela

    2012-12-01

    Blue green algae supplements (BGAS) are generally proposed as health-promoting natural products for their purported beneficial effects. Spirulina spp. and Aphanizomenon flos aquae are mainly used in BGAS production. They are usually collected from the natural environment, where other potentially toxic cyanobacteria can be present, making possible BGAS contamination by cyanotoxins, with potential risk for human health. In this work we apply a combined approach, by using chemical and molecular techniques, on BGAS of 17 brands available in Italy. Samples containing Spirulina-only were free of contamination. The Aphanizomenon flos aquae-based samples were contaminated by highly variable levels of microcystins (MC-LR and MC-LA congeners), up to 5.2 μg MC-LR equivalents per gram product. The highest variability (up to 50 fold) was among batches of the same brand, although intra-batch differences were also evidenced. PCR analyses were positive only for the presence of Microcystis sp., identified as the toxin-producing species responsible for contamination. At the maximum contamination levels found, a risk for consumers can be expected following chronic or sub-chronic exposure to a reasonable daily BGAS consumption of 4 g. The need for a strict monitoring by producers and Health Authority to assure an adequate protection for consumers is underscored. Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. Bio-oil production through pyrolysis of blue-green algae blooms (BGAB): Product distribution and bio-oil characterization

    International Nuclear Information System (INIS)

    Hu, Zhiquan; Zheng, Yang; Yan, Feng; Xiao, Bo; Liu, Shiming

    2013-01-01

    Pyrolysis experiments of blue-green algae blooms (BGAB) were carried out in a fixed-bed reactor to determine the effects of pyrolysis temperature, particle size and sweep gas flow rate on pyrolysis product yields and bio-oil properties. The pyrolysis temperature, particle size and sweep gas flow rate were varied in the ranges of 300–700 °C, below 0.25–2.5 mm and 50–400 mL min −1 , respectively. The maximum oil yield of 54.97% was obtained at a pyrolysis temperature of 500 °C, particle size below 0.25 mm and sweep gas flow rate of 100 mL min −1 . The elemental analysis and calorific value of the oil were determined, and the chemical composition of the oil was investigated using gas chromatography–mass spectroscopy (GC–MS) technique. The analysis of bio-oil composition showed that bio-oil from BGAB could be a potential source of renewable fuel with a heating value of 31.9 MJ kg −1 . - Highlights: ► Bio-oil production from pyrolysis of blue-green algae blooms in fixed bed reactor. ► Effects of pyrolysis conditions on product distribution were investigated. ► The maximum bio-oil yield reached 54.97 wt %. ► The bio-oil has high heating value and may be suitable as renewable fuel. ► Pyrolysis of algal biomass beneficial for energy recovery, eutrophication control

  17. Removal of blue-green algae using the hybrid method of hydrodynamic cavitation and ozonation.

    Science.gov (United States)

    Wu, Zhilin; Shen, Haifeng; Ondruschka, Bernd; Zhang, Yongchun; Wang, Weimin; Bremner, David H

    2012-10-15

    A suspension of Microcystis aeruginosa (30 μg L(-1)chlorophyll a) was circulated in a hydrodynamic cavitation device and ozone was introduced at the suction side of the pump. The removal of algae over 10 min using hydrodynamic cavitation alone and ozone alone is less than 15% and 35%, respectively. The destruction of algae rises significantly from 24% in the absence of the orifice to 91% with the optimized orifice on 5 min of processing using hydrodynamic cavitation along with ozone (HC/O(3)) and the utilization of ozone increases from 32% to 61%. Interestingly, the suction process is more effective than the extrusion method (positive pressure) and the optimal bulk temperature for algal elimination was found to be 20 °C. Increasing the input concentration of ozone is favorable for the removal of algae but leads to a greater loss of ozone and a decrease in the utilization of ozone. Under the optimal conditions, the algal cells and chlorophyll a are completely destroyed in 10 min by use of the hybrid method. Copyright © 2012 Elsevier B.V. All rights reserved.

  18. Quality evaluation of the edible blue-green alga Nostoc flagelliforme using a chlorophyll fluorescence parameter and several biochemical markers.

    Science.gov (United States)

    Gao, Xiang; Yang, Yiwen; Ai, Yufeng; Luo, Hongyi; Qiu, Baosheng

    2014-01-15

    Nostoc flagelliforme is an edible blue-green alga with herbal and dietary values. Due to the diminishing supply of natural N. flagelliforme and the large investment on the development of its cultivation technology, it is anticipated that artificially cultured N. flagelliforme will soon sustain the market supply. Once this change occurs, the storage-associated quality problem will become the focus of attention for future trade. In this paper, we used a chlorophyll fluorescence parameter, maximum quantum efficiency of Photosystem II (Fv/Fm), and several biomarkers to evaluate the quality of several N. flagelliforme samples. It was found that longer storage times resulted in darker coloured solutions (released pigments) and decreased amounts of chlorophyll a (Chl a) and water-soluble sugars (WSS). Additionally, a higher Fv/Fm value suggests better physiological recovery and quality. In actual application, determination of Fv/Fm would be the first step for evaluating the quality of N. flagelliforme, and the biochemical indexes would serve as good secondary markers. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. Induction of mutations in blue-green alga Anacystis nidulans by consolidated and split UV irradiation

    International Nuclear Information System (INIS)

    Amla, D.V.

    1979-01-01

    Ultraviolet mutability of consolidated and split dose treatment in A. nidulans was investigated with reference to induction of phage- and streptomycin-resistant markers. The consolidated UV treatment induced both the markers about 100-150-fold, whereas under photoreactivating conditions the survival of alga was enhanced and mutation frequency was decreased. The split UV treatment with 6 hr dark incubation between two UV exposures enhanced the survival and mutation frequencies to 500-700 fold above the back-ground level. The data give indirect evidence for the presence of error-prone dark repair system in this organism. (auth.)

  20. Induction of mutations in the blue-green alga Plectonema boryanum Gomont

    International Nuclear Information System (INIS)

    Singh, R.N.; Kashyap, A.K.

    1977-01-01

    Mutations to cyanophage and streptomycin resistance were induced in the filamentous blue-gree alga Plectonema boryanum IU 594 after treatment with ultraviolet irradiation, N-methyl-N'-nitro-Nnitrosoguanidine, acriflavine, 2-aminopurine and caffeine. Phage-resistant mutants were obtained with all the mutagens tested. Their efficiencies were in the order: MNNG>UV>acriflavine >2-AP>caffeine. In contrast, the drug-resistant mutants were not induced by base analogues: the efficiencies were: acriflavine>MNNG>UV. Lethal and mutational lesions induced with UV were efficiently repaired under photo-reactivating conditions whereas post-treatment with caffeine resulted in enhanced mutation frequencies especially at low UV doses. Neither survival nor mutagenesis was enhanced by keeping the MNNG-treated population in subdued light

  1. Production of nutritionally-deficient mutants of the axenic blue-green alga Anabaena flos-aquae NRC-44-1 by ultraviolet irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, H D; Gorham, P R

    1975-01-01

    Anabaena flos-aquae NRC-44-1 is a freshwater nitrogen fixing blue-green alga of some ecological significance because of its toxicity. In axenic culture and possibly also in nature, the alga is highly susceptible to lysis at certain stages of its growth. Nothing is known about genetic phenomena governing toxin production, nitrogen fixation or other characteristics of this organism, mainly because of unavailability of mutant strains that could be utilized in genetic experiments. With the object of overcoming this obstacle to the eventual study of genetics of Anabaena flos-aquae, attempts were made to produce and isolate nutritionally-deficient mutants of this species.

  2. The use of 15N-labelled dinitrogen in the study of nitrogen fixation by blue-green algae

    International Nuclear Information System (INIS)

    Jones, J.

    1985-01-01

    Prior to the development of the acetylene reduction technique 15 N was used as the main qualitative and quantitative measure of nitrogen fixation by free-living cyanobacteria in a variety of aquatic and terrestrial habitats. Despite its expense and the technical difficulty, 15 N is a major tool in the study of cyanobacteria, for example, incorporation of 15 N 2 is the definitive test for nitrogen fixation; it is used in the determination of the correct ratio of acetylene reduction to nitrogen fixation, in in situ nitrogen fixation assays, in tracing the formation and fate of extra-cellular nitrogen and in measuring the turnover and grazing rates of cyanobacterial intra-cellular nitrogen. These latter studies show that 15 N-labelled extra-cellular nitrogen can serve as nitrogen sources for a variety of bacteria, fungi, algae and higher plants, and that cyanobacteria are graced and digested by a variety of animals. The turnover rates of cyanobacterial 15 N-labelled cells are dependent on the type of cell, species, environmental conditions and the availability of degrading organisms. The breakdown products are rapidly mineralised and used as nitrogen sources by higher plants. (author)

  3. One Health and Toxic Cyanobacteria

    Science.gov (United States)

    One Health and toxic cyanobacteria Blooms of toxic freshwater blue-green algae or cyanobacteria (HABs) have been in the news after HABs associated with human and animal health problems have been reported in Florida, California and Utah during 2016. HABs occur in warm, slow moving...

  4. Eutrophication and cyanobacteria in South Africa’s standing water bodies: A view from space

    CSIR Research Space (South Africa)

    Matthews, MW

    2015-05-01

    Full Text Available Satellite remote sensing can make a significant contribution to monitoring water quality in South African standing water bodies. Eutrophication, defined as enrichment by nutrients, and toxin-producing cyanobacteria (blue-green algae) blooms pose a...

  5. Experimental Substantiation of the Possibility of Developing Selenium- and Iodine-Containing Pharmaceuticals Based on Blue-Green Algae Spirulina Platensis

    CERN Document Server

    Mosulishvili, L M; Belokobylsky, A I; Khisanishvili, L A; Frontasyeva, M V; Pavlov, C C; Gundorina, S F

    2001-01-01

    The great potential of using blue-green algae Spirulina platensis as a matrix for the production of selenium- and iodine-containing pharmaceuticals is shown experimentally. The background levels of 31 major, minor and trace elements (Na, Mg, Al, Cl, K, Ca, Sc, V, Cr, Mn, Fe, Co, Ni (using -reaction), As, Br, Zn, Rb, Mo, Ag, Sb, I, Ba, Sm, Tb, Tm, Hf, Ta, W, Au, Hg, Th) in Spirulina platensis biomass were determined by means of epithermal neutron activation analysis. The dependence of selenium and iodine accumulation in spirulina biomass on a nutrient medium loding of the above elements was characterised. To demonstrate the possibilities of determining toxic element intake by spirulina biomass, mercury was selected. The technological parameters for production of iodinated treatment-and-prophylactic pills are developed.

  6. Comparative effects of the blue green algae Nodularia spumigena and a lysed extract on detoxification and antioxidant enzymes in the green lipped mussel (Perna viridis)

    International Nuclear Information System (INIS)

    Davies, Warren R.; Siu, William H.L.; Jack, Ralph W.; Wu, Rudolf S.S.; Lam, Paul K.S.; Nugegoda, Dayanthi

    2005-01-01

    Nodularia spumigena periodically proliferates to cause toxic algal blooms with some aquatic animals enduring and consuming high densities of the blue green algae or toxic lysis. N. spumigena contains toxic compounds such as nodularin and lipopolysaccharides. This current work investigates physiological effects of exposure from bloom conditions of N. spumigena cells and a post-bloom lysis. Biochemical and antioxidative biomarkers were comparatively studied over an acute 3-day exposure. In general, a post-bloom N. spumigena lysis caused opposite physiological responses to bloom densities of N. spumigena. Specifically, increases in glutathione (GSH) and glutathione peroxidase (GPx) and decreases in glutathione S-transferase (GST) were observed from the N. spumigena lysis. In contrast, N. spumigena cell densities decreased GSH and increased GST and lipid peroxidation (LPO) in mussels. Findings also suggest that at different stages of a toxic bloom, exposure may result in toxic stress to specific organs in the mussel

  7. Experimental substantiation of the possibility of developing selenium- and iodine-containing pharmaceuticals based on blue-green algae Spirulina platensis.

    Science.gov (United States)

    Mosulishvili, L M; Kirkesali, E I; Belokobylsky, A I; Khizanishvili, A I; Frontasyeva, M V; Pavlov, S S; Gundorina, S F

    2002-08-22

    The great potential of using blue-green algae Spirulina platensis as a matrix for the production of selenium- and iodine-containing pharmaceuticals is shown experimentally. The background levels of 31 major, minor and trace elements (Na, Mg, Al, Cl, K, Ca, Sc, V, Cr, Mn, Fe, Co, Ni (using (n,p) reaction), As, Br, Zn, Rb, Mo, Ag, Sb, I, Ba, Sm, Tb, Tm, Hf, Ta, W, Au, Hg, Th) in S. platensis biomass were determined by means of epithermal neutron activation analysis. The dependence of selenium and iodine accumulation in spirulina biomass on a nutrient medium loading of the above elements was characterized. To demonstrate the possibilities of determining toxic element intake by spirulina biomass, mercury was selected. The technological parameters for production of iodinated treatment-and-prophylactic pills are developed.

  8. Experimental substantiation of the possibility of developing selenium- and iodine-containing pharmaceuticals based on blue-green algae Spirulina platensis

    International Nuclear Information System (INIS)

    Mosulishvili, L.M.; Kirkesali, E.I.; Belokobyl'skij, A.I.; Khizanishvili, A.I.; Frontas'eva, M.V.; Pavlov, S.S.; Gundorina, S.F.

    2001-01-01

    The great potential of using blue-green algae Spirulina platensis as a matrix for the production of selenium- and iodine-containing pharmaceuticals is shown experimentally. The background levels of 31 major, minor and trace elements (Na, Mg, Al, Cl, K, Ca, Sc, V, Cr, Mn, Fe, Co, Ni (using (n,p)-reaction), As, Br, Zn, Rb, Mo, Ag, Sb, I, Ba, Sm, Tb, Tm, Hf, Ta, W, Au, Hg, Th) in Spirulina platensis biomass were determined by means of epithermal neutron activation analysis. The dependence of selenium and iodine accumulation in spirulina biomass on a nutrient medium loading of the above elements was characterised. To demonstrate the possibilities of determining toxic element intake by spirulina biomass, mercury was selected. The technological parameters for production of iodinated treatment-and-prophylactic pills are developed

  9. Effects of acetylene and carbon monoxide on long-term hydrogen production by Mastigocladus laminosus, a thermophilic blue-green alga

    Energy Technology Data Exchange (ETDEWEB)

    Miura, Y; Yokoyama, H; Takahara, K; Miyamoto, K

    1982-01-01

    Long-term H/sub 2/ production by a thermophilic and heterocystous blue-green alga (cyanobacterium) Mastigocladus laminosus was studied under the conditions when acetylene and carbon monoxide were supplemented to the gas phase of the culture vessel. The addition of both gases enhanced H/sub 2/ evolution by nitrogen-starved cells. The concentrations of acetylene and carbon monoxide in the gas phase of argon/CO/sub 2/ (97.5/2.5) were 10% and 0.2 to 1%, respectively, for the maximum H/sub 2/ production. Renewals of the gas phase, in addition to the addition of acetylene and carbon monoxide, were necessary for durable H/sub 2/ production. Since the concentrations of both H/sub 2/ and O/sub 2/ accumulated in the gas phase were minimized after the renewals, the H/sub 2/ uptake activity, which was not completely inhibited by acetylene and carbon monoxide, was reduced and thereby H/sub 2/ evolution was restored. Under such conditions, H/sub 2/ production for up to 20 days was observed under argon and N/sub 2/ atmospheres with average rats of 3.9 and 3.3..mu..l/mg dry wt/h, respectively. H/sub 2/ evolution for 15 days was observed even under an air atmosphere containing acetylene and carbon monoxide. It was thus shown that prolonged production of H/sub 2/ was possible by the use of a blue-green alga which exhibits a high activity of H/sub 2/ uptake under nitrogen-starved conditions.

  10. The Northeast Cyanobacteria Monitoring Program: One Program, Three Opportunities for You To Get Involved!

    Science.gov (United States)

    If you ever have noticed a waterbody with a layer of green scum coating its surface or a slick green film resembling a paint spill, you likely have witnessed a cyanobacteria bloom. Cyanobacteria, sometimes referred to as blue-green algae, are tiny organisms found naturally in aqu...

  11. 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...

  12. Cyanobacteria HABs - Causes, Prevention, and Mitigation Workgroup Report.

    Science.gov (United States)

    Cyanobacteria (blue-green algae) are estimated to have evolved 3.5 billion years ago, at which time they began to add oxygen to the existing anaerobic atmosphere, actually changing the chemistry of the planet and allowing new life forms to evolve. These ubiquitous microbes are capable of tolerating ...

  13. The toxins of Cyanobacteria.

    Science.gov (United States)

    Patocka, J

    2001-01-01

    Cyanobacteria, formerly called "blue-green algae", are simple, primitive photosynthetic microorganism wide occurrence in fresh, brackish and salt waters. Forty different genera of Cyanobacteria are known and many of them are producers of potent toxins responsible for a wide array of human illnesses, aquatic mammal and bird morbidity and mortality, and extensive fish kills. These cyanotoxins act as neurotoxins or hepatotoxins and are structurally and functionally diverse, and many are derived from unique biosynthetic pathways. All known cyanotoxins and their chemical and toxicological characteristics are presented in this article.

  14. Control of cytokinin and auxin homeostasis in cyanobacteria and algae

    Czech Academy of Sciences Publication Activity Database

    Žižková, Eva; Kubeš, Martin; Dobrev, Petre; Přibyl, Pavel; Šimura, J.; Zahajská, Lenka; Záveská Drábková, Lenka; Novák, Ondřej; Motyka, Václav

    2017-01-01

    Roč. 119, č. 1 (2017), s. 151-166 ISSN 0305-7364 R&D Projects: GA ČR(CZ) GA16-14649S; GA ČR GA15-22322S; GA MŠk(CZ) LO1204 Institutional support: RVO:61389030 ; RVO:67985939 Keywords : solid-phase extraction * performance liquid-chromatography * yucca flavin monooxygenases * tandem mass-spectrometry * abscisic-acid * arabidopsis-thaliana * indole-3-acetic-acid iaa * endogenous cytokinins * chlorella-vulgaris * phenylacetic acid * Cytokinin * auxin * cyanobacteria * algae * metabolism * cytokinin oxidase/dehydrogenase * cytokinin 2-methylthioderivatives * trans-zeatin * indole-3-acetic acid * tRNA Subject RIV: EF - Botanics OBOR OECD: Plant sciences, botany Impact factor: 4.041, year: 2016

  15. De novo quence analysis and intact mass measurements for characterization of phycocyanin subunit isoforms from the blue-green alga Aphanizomenon flos-aquae

    DEFF Research Database (Denmark)

    Rinalducci, Sara; Roepstorff, Peter; Zolla, Lello

    2009-01-01

    isothiocyanate (SPITC) and MALDI-TOF/TOF analyses, facilitated the acquisition of sequence information for AFA phycocyanin subunits. In fact, SPITC-derivatized peptides underwent facile fragmentation, predominantly resulting in y-series ions in the MS/MS spectra and often exhibiting uninterrupted sequences of 20...... of phycocyanin subunits was also revealed; subsequently Intact Mass Measurements (IMMs) by both MALDI- and ESI-MS supported the detection of these protein isoforms. Finally, we discuss the evolutionary importance of phycocyanin isoforms in cyanobacteria, suggesting the possible use of the phycocyanin operon...

  16. Active substance from some blue green algal species used as ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-05-10

    May 10, 2010 ... pathogens, has recently received considerable attention as a new source of novel .... mass spectra with the profiles from the Wiley GC-MS 275 libraries. Khairy and ..... Selective isolation of blue-green algae from water and soil ...

  17. Biofilm forming cyanobacteria, algae and fungi on two historic monuments in Belgrade, Serbia

    Directory of Open Access Journals (Sweden)

    Ljaljević-Grbić Milica

    2010-01-01

    Full Text Available Biofilm on the sandstone substrata of the bridge 'Brankov most' and on the granite substrata of the 'Monument of the Unknown Hero' contains a complex consortia of cyanobacteria, algae, and fungi. Coccoid and filamentous cyanobacteria, green algae and diatoms make up the photosynthetic part of the biofilm while hyphal fragments, chlamydospores, fruiting bodies and spores take part as fungal components. These structures make a dense layer by intertwining and overlapping the stone surface. Five cyanobacterial, 11 algal and 23 fungal taxa were found. The interaction of the biofilm's constituents results in the bioweathering of the stone substrata through mechanical penetration, acid corrosion and the production of secondary mycogenic biominerals. .

  18. Genetics of blue-green algae

    International Nuclear Information System (INIS)

    Ladha, J.K.; Kumar, H.D.

    1978-01-01

    Mutagenesis and genetics of cyanophyceae are reviewed. Mutant isolation, ultraviolet inactivation, reactivation and production of mutants resistant or sensitive to ultraviolet light, control of gene expression, genetic transfer and mapping are discussed. (UK)

  19. Effect of ultraviolet radiation on laboratory cultures of green algae and cyanobacteria

    International Nuclear Information System (INIS)

    Palffy, K.; Ordog, V.; Voros, L.

    2004-01-01

    Since the discovery of the ozone hole, an increasing amount of work has been devoted to measuring the impact of the UV-radiation on living organisms. In this point of view, algae as the primer producers of aquatic ecosystems, get to the central part of the interest. The aim of the study was to study the effect of ultraviolet radiation on laboratory cultures of green algae and cyanobacteria

  20. Cyanobacteria, algae and microfungi present in biofilm from Božana Cave (Serbia

    Directory of Open Access Journals (Sweden)

    Slađana Popović

    2015-05-01

    Full Text Available Phototrophic microorganisms (cyanobacteria and algae and microfungi, were identified from biofilm on the walls of the entrance of BožanaCavein west Serbia. Temperature, relative humidity and light intensity were measured, and chlorophyll a content determined. Light intensity differed from the entrance inwards. However, Chl a content was not proportional to light intensity, instead it was positively correlated to biofilm weight. Biofilm samples from two sites were also observed using a scanning electron microscope. Coccoid forms of cyanobacteria were abundant at the sampling site with the lowest light intensity, while members of the order Nostocales were predominant at the sampling site with the highest light intensity measured. Cyanobacteria were the dominant group of phototrophs colonizing cave walls (29 taxa, with the order Chroococcales prevailing (21 taxa. The most frequently documented cyanobacteria were species from genera Gloeocapsa, Scytonema, Aphanocapsa and Chroococcus. Desmococcus olivaceus and Trentepohlia aurea were the only green algae documented on cave walls. Ascomycetes were common (e.g. Alternaria, Aspergillus, Cladosporium, Epicoccum, Penicillum and Trichoderma, while zygomycetes and oomycetes were less frequent. The different color of each biofilm sample was ascribed to the presence of various different species of cyanobacteria and algae.

  1. Estrogenic activity in extracts and exudates of cyanobacteria and green algae

    Czech Academy of Sciences Publication Activity Database

    Sychrová, E.; Štěpánkdová, T.; Nováková, K.; Bláha, Luděk; Giesy, J.P.; Hilscherová, K.

    2012-01-01

    Roč. 39, č. 1 (2012), s. 134-140 ISSN 0160-4120 R&D Projects: GA ČR GA524/08/0496 Institutional support: RVO:67985939 Keywords : cyanobacteria * endocrine disruption * estrogenicity * algae * phytoplankton Subject RIV: EF - Botanics Impact factor: 6.248, year: 2012

  2. Toxicity of trichloroethylene (TCE) on some algae and cyanobacteria

    Czech Academy of Sciences Publication Activity Database

    Lukavský, Jaromír; Furnadzhieva, S.; Dittrt, František

    2011-01-01

    Roč. 86, č. 2 (2011), 226-231 ISSN 0007-4861 R&D Projects: GA MŠk 1M0571 Institutional research plan: CEZ:AV0Z60050516; CEZ:AV0Z20600510 Keywords : toxicity * cyanobacteria * trichloroethylene Subject RIV: EF - Botanics Impact factor: 1.018, year: 2011

  3. 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 ...

  4. Recent developments in therapeutic applications of Cyanobacteria.

    Science.gov (United States)

    Raja, Rathinam; Hemaiswarya, Shanmugam; Ganesan, Venkatesan; Carvalho, Isabel S

    2016-05-01

    The cyanobacteria (blue-green algae) are photosynthetic prokaryotes having applications in human health with numerous biological activities and as a dietary supplement. It is used as a food supplement because of its richness in nutrients and digestibility. Many cyanobacteria (Microcystis sp, Anabaena sp, Nostoc sp, Oscillatoria sp., etc.) produce a great variety of secondary metabolites with potent biological activities. Cyanobacteria produce biologically active and chemically diverse compounds belonging to cyclic peptides, lipopeptides, fatty acid amides, alkaloids and saccharides. More than 50% of the marine cyanobacteria are potentially exploitable for extracting bioactive substances which are effective in killing cancer cells by inducing apoptotic death. Their role as anti-viral, anti-tumor, antimicrobial, anti-HIV and a food additive have also been well established. However, such products are at different stages of clinical trials and only a few compounds have reached to the market.

  5. A cost-effective microbial fuel cell to detect and select for photosynthetic electrogenic activity in algae and cyanobacteria

    NARCIS (Netherlands)

    Luimstra, V.M.; Kennedy, S.J.; Güttler, J.; Wood, S.A.; Williams, D.E.; Packer, M.A.

    2014-01-01

    This work describes the development of an easily constructed, cost-effective photosynthetic microbial fuel cell design with highly reproducible electrochemical characteristics that can be used to screen algae and cyanobacteria for photosynthetic electrogenic activity. It is especially suitable for

  6. In vitro antioxidant activity assessment on alcoholic extract of cyanobacteria cultures from Spirulina platensis

    OpenAIRE

    Senthilkumaran Jagadeesh J, Jaiganesh K, Somasundaram G

    2013-01-01

    The antioxidant supplementation such as vitamin C, E, A and beta carotene etc, has proven to prevent the process of ageing caused by free radicals. Antioxidants either prevent free radical production or counteract the impeding damage by doing so they are involved in the protection and prevention of cellular damage which is the common pathway for cancer, aging and much disease. The cyanobacteria is a blue green micro algae believed to be a rich antioxidant source, found in abundance in Spiruli...

  7. Eutrophication and cyanobacteria in South Africa's standing water bodies: A view from space

    OpenAIRE

    Matthews, Mark W.; Bernard, Stewart

    2015-01-01

    Satellite remote sensing can make a significant contribution to monitoring water quality in South African standing water bodies. Eutrophication, defined as enrichment by nutrients, and toxin-producing cyanobacteria (blue-green algae) blooms pose a significant threat to the quality of South African surface water bodies. The status and trends of chlorophyll a (chl-a, a proxy for eutrophication), cyanobacterial blooms and cyanobacterial surface scum were determined for South Africa’s 50 largest ...

  8. [Investigation of algae pollution in Xiliu Lake and identification of toxic cyanobacteria by whole-cell PCR].

    Science.gov (United States)

    Ban, Hai-qun; Zhuang, Dong-gang; Zhu, Jing-yuan; Ba, Yue

    2006-03-01

    To investigate the contaminative condition of the floating algae (especially toxic cyanobacteria) in Xiliu Lake, and establish a whole-cell PCR method for identifying the toxic cyanobacteria. The surface water of Xiliu Lake was sampled by plastic sampler from March, 2004, and the number of algae was counted by using blood cell counter. The phycocyanin intergenic spacer region (PC-IGS) and microcystin synthetase gene B (mcyB) were identified by whole-cell PCR in water samples, and the amplified product of mcyB was inserted into T vector and sequenced. Cyanobacteria, Chlorophyta, Bacillariophyta and Euglenophyta were main algae, and cyanobacteria was the dominant algae in summer and autumn. From July 7 to September 27,2 004, PC-IGS was detected positively in 11 samples, and from July 29 to September 27, mcyB was-detieted positively in 9 samples. Compared with the reported mcyB of Microcystis aeruginosa in Genbank, the homology of gene sequence was more than 97 t he homology of amino acid sequence was more than 94%. In summer and autumn toxic cyanobacteria could be detected in Xiliu Lake. Toxic cyanobacteria could be identified successfully by whole-cell PCR.

  9. One Health and Toxic Cyanobacteria | Science Inventory | US ...

    Science.gov (United States)

    One Health and toxic cyanobacteria Blooms of toxic freshwater blue-green algae or cyanobacteria (HABs) have been in the news after HABs associated with human and animal health problems have been reported in Florida, California and Utah during 2016. HABs occur in warm, slow moving or stagnant surface waters that are enriched with nutrients such as nitrogen and phosphorous. People are exposed to potentially toxic HABs during recreation in contaminated water, after exposure to contaminated drinking water or to blue-green algae supplements. Animals may be exposed to toxic HABs after drinking contaminated surface waters or coming into contact with HABs then ingesting cyanobacteria from their bodies during self-grooming activities. As HABs are being reported more frequently in the US, it is important for veterinarians to secure good exposure histories and to recognize the potential signs and health consequences of HAB exposures. We will review the current knowledge about human and animal health effects associated with freshwater HABs and scenarios that pose the highest risks for illnesses and deaths. This abstract does not necessarily reflect EPA policy. This is a summary of One Health and Cyanobacteria for public health and public practice veterinarians at the American Veterinary Medical Association annual convention. This product is associated with SSWR 4.01B

  10. Ecological-floristic analysis of soil algae and cyanobacteria on the Tra-Tau and Yurak-Tau Mounts, Bashkiria

    Science.gov (United States)

    Bakieva, G. R.; Khaibullina, L. S.; Gaisina, L. A.; Kabirov, R. R.

    2012-09-01

    The species composition of the soil algae and cyanobacteria in the Tra-Tau and Yurak-Tau mountains is represented by 136 species belonging to five phyla: Cyanobacteria (56 species), Chlorophyta (52 species), Xanthophyta (13 species), Bacillariophyta (12 species), and Eustigmatophyta (3 species). Hantzschia amphioxys var. amphioxys, Hantzschia amphioxys var. constricta, Klebsormidium flaccidum, Leptolyngbya foveolarum, Luticola mutica, Navicula minima var. minima, Nostoc punctiforme, Phormidium jadinianum, Phormidium autumnale, and Pinnularia borealis were identified more often than other species. The composition of the algal flora depended on the soil properties; the higher plants also had a significant influence on the species composition of the soil algae.

  11. Competition between cyanobacteria and green algae at low versus elevated CO2: who will win, and why?

    Science.gov (United States)

    Ji, Xing; Verspagen, Jolanda M H; Stomp, Maayke; Huisman, Jef

    2017-06-01

    Traditionally, it has often been hypothesized that cyanobacteria are superior competitors at low CO2 and high pH in comparison with eukaryotic algae, owing to their effective CO2-concentrating mechanism (CCM). However, recent work indicates that green algae can also have a sophisticated CCM tuned to low CO2 levels. Conversely, cyanobacteria with the high-flux bicarbonate uptake system BicA appear well adapted to high inorganic carbon concentrations. To investigate these ideas we studied competition between three species of green algae and a bicA strain of the harmful cyanobacterium Microcystis aeruginosa at low (100 ppm) and high (2000 ppm) CO2. Two of the green algae were competitively superior to the cyanobacterium at low CO2, whereas the cyanobacterium increased its competitive ability with respect to the green algae at high CO2. The experiments were supported by a resource competition model linking the population dynamics of the phytoplankton species with dynamic changes in carbon speciation, pH and light. Our results show (i) that competition between phytoplankton species at different CO2 levels can be predicted from species traits in monoculture, (ii) that green algae can be strong competitors under CO2-depleted conditions, and (iii) that bloom-forming cyanobacteria with high-flux bicarbonate uptake systems will benefit from elevated CO2 concentrations. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  12. Observations on aerophytic cyanobacteria and algae from ten caves in the Ojców National Park

    Directory of Open Access Journals (Sweden)

    Joanna Czerwik-Marcinkowska

    2013-04-01

    Full Text Available This study, carried out in 2010–11, focuses on species composition and distribution of cyanobacterial and algal communities colonizing ten caves (Biała, Ciemna, Koziarnia, Krakowska, Łokietka, Okopy Wielka Dolna, Sąspowska, Sypialnia, Zbójecka and Złodziejska Caves in the Ojców National Park (South Poland. A total of 85 taxa were identified, 35 of them belonging to cyanobacteria, 30 chlorophytes, and 20 belonging to other groups of algae. Aerophytic cyanobacteria dominated in these calcareous habitats. Nine species, Gloeocapsa alpina, Nostoc commune, Chlorella vulgaris, Dilabifilum arthopyreniae, Klebsormidium flaccidum, Muriella decolor, Neocystis subglobosa, and Orthoseira roseana, were the most abundant taxa in all the caves. The investigated microhabitats offer relatively stable microclimatic conditions and are likely to be responsible for the observed vertical distribution of aerophytic cyanobacteria and algae.

  13. Blue green component and integrated urban design

    Directory of Open Access Journals (Sweden)

    Stanković Srđan M.

    2016-01-01

    Full Text Available This paper aims to demonstrate the hidden potential of blue green components, in a synergetic network, not as separate systems, like used in past. The innovative methodology of the project Blue Green Dream is presented through examples of good practice. A new approach in the project initiate thoughtful planning and remodeling of the settlement for the modern man. Professional and scientific public is looking for way to create more healthy and stimulating place for living. However, offered integrative solutions still remain out of urban and architectural practice. Tested technologies in current projects confirmed measurability of innovative approaches and lessons learned. Scientific and professional contributions are summarized in master's and doctoral theses that have been completed or are in process of writing.

  14. The evolution of blue-greens and the origins of chloroplasts

    Science.gov (United States)

    Schwartz, R. M.; Dayhoff, M. O.

    1981-01-01

    All of the available molecular data support the theory that the chloroplasts of eukaryote cells were originally free-living blue-greens. Of great interest is what the relationships are between contemporary types of blue-greens and eukaryote chloroplasts and whether the chloroplasts of the various eukaryotes are the result of one or more than one symbiosis. By combining information from phylogenetic trees based on cytochrome c6 and 2Fe-2S ferredoxin sequences, it is shown that the chloroplasts of a number of eukaryote algae as well as the protist Euglena are polyphyletic; the chloroplasts of green algae and the higher plants may be the result of a single symbiosis.

  15. Blue-Green Solutions in Urban Development

    Science.gov (United States)

    Karlsson, Caroline; Kalantari, Zahra

    2017-04-01

    With the ongoing urbanisation and increasing pressure for new housing and infrastructure, the nexus of developing compact, energy-efficient and yet liveable and sustainable cities is urgent to address. In this context, blue-green spaces and related ecosystem services (ES) are critical resources that need to be integrated in policy and planning of urban. Among the ES provided by blue-green spaces, regulating ES such as water retention and purification are particularly important in urban areas, affecting water supply and quality, related cultural ES and biodiversity, as well as cities potential to adapt to climate change. Blue-green infrastructure management is considered a sustainable way to reducing negative effects of urbanisation, such as decreasing flood risks, as well as adapting to climate change for example by controlling increasing flood and drought risks. Blue-green infrastructure management can for example create multifunctional surfaces with valuable environmental and social functions and generally handle greenways and ecological networks as important ecosystem service components, for example for stormwater regulation in a sustainable urban drainage system. The Norrström drainage basin (22,000 km2) is a large demonstrator for Blue-green infrastructure management. Both urbanisation and agriculture are extensive within this basin, which includes the Swedish capital Stockholm and is part of the fertile Swedish belt. Together, the relatively high population density combined with agricultural and industrial activities in this region imply large eutrophication and pollution pressures, not least transferred through storm runoff to both inland surface waters and the coastal waters of the Baltic Sea. The ecosystems of this basin provide highly valued but also threatened services. For example, Lake Mälaren is the single main freshwater supply for the Swedish capital Stockholm, as well as a key nutrient retention system that strongly mitigates waterborne nutrient

  16. 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.

  17. Floristic account of the marine benthic algae from Jarvis Island and Kingman Reef, Line Islands, Central Pacific

    Directory of Open Access Journals (Sweden)

    Vroom, P.S.

    2012-05-01

    Full Text Available The marine benthic algae from Jarvis Island and Kingman Reef were identified from collections obtained from the Whippoorwill Expedition in 1924, the Itasca Expedition in 1935, the U.S. Coast Guard Cutter Taney in 1938, the Smithsonian Institution’s Pacific Ocean Biological Survey Program in 1964 and the U.S. National Oceanic and Atmospheric Administration’s Reef Assessment and Monitoring Program (RAMP in 2000, 2001, 2002, 2004 and 2006. A total of 124 species, representing 8 Cyanobacteria (blue-green algae, 82 Rhodophyta (red algae, 6 Heterokontophyta (brown algae and 28 Chlorophyta (green algae, are reported from both islands. Seventy-nine and 95 species of marine benthic algae are recorded from Jarvis Island and Kingman Reef, respectively. Of the 124 species, 77 species or 62% (4 blue-green algae, 57 red algae, 2 brown algae and 14 green algae have never before been reported from the 11 remote reefs, atolls and low islands comprising the Line Islands in the Central Pacific.

  18. Water Pollution, and Treatments Part III: Biodegradation of Oil in Refineries Waste Water and Oils Adsorbed in Agricultural Wastes by Selected Strains of Cyanobacteria

    International Nuclear Information System (INIS)

    El-Emary, M.M.; Ali, N.A.; Naguib, M.M.

    2011-01-01

    The main objective of this study is to determine the biological degradation of oil hydrocarbons and sulfur compounds of Marine Balayim crude oil and its refined products by selected indigenous Cyanobacteria strains. The oils used were Marine Balayim crude oil, skimmed oil and some refined products such as gasoline, kerosene, gas oil, fuel oil and petroleum coke. The selected organisms in the current study are the Blue-Green Algae Cyanobacteria, Oscillatoria limentica. This organism was collected from the hyper saline environment of the solar lake in Taba, Sinai, Egypt. The results obtained revealed that the utilization of such strains can be used for the bioremediation of oily waste water.

  19. Growth of soil algae and cyanobacteria on gold mine tailings material

    Directory of Open Access Journals (Sweden)

    Tanya Seiderer

    2017-11-01

    Full Text Available The goal of revegetation of gold mine tailings storage facilities is to reduce aeolian pollution, nutrient leaching and erosion caused by exposure to wind and water. The establishment of biological soil crusts may prove to be a more cost-effective way to reach the same goal and the aim of this study was therefore to determine if it is possible to establish algae and cyanobacteria on gold mine tailings. Different treatments of Chlamydomonas, Microcoleus and Nostoc were inoculated on gold mine tailings in controlled conditions and algal growth was measured on all of the treatments after 6 weeks. Nostoc treatments had the highest chlorophyll-a concentrations and produced a surface crust, while Chlamydomonas treatments penetrated the tailings material and provided the strongest crust. The results were promising but more research is necessary to determine the best organism, or combination of organisms, to colonise mine tailings and to eventually produce biological crusts. Significance: Determination of the best organisms to colonise mine tailings and to produce biological crusts for the revegetation of gold mine tailings storage facilities.

  20. The "Martian" flora: new collections of vascular plants, lichens, fungi, algae, and cyanobacteria from the Mars Desert Research Station, Utah

    Science.gov (United States)

    Freebury, Colin E.; Hamilton, Paul B.; Saarela, Jeffery M.

    2016-01-01

    Abstract The Mars Desert Research Station is a Mars analog research site located in the desert outside of Hanksville, Utah, U.S.A. Here we present a preliminary checklist of the vascular plant and lichen flora for the station, based on collections made primarily during a two-week simulated Mars mission in November, 2014. Additionally, we present notes on the endolithic chlorophytes and cyanobacteria, and the identification of a fungal genus also based on these collections. Altogether, we recorded 38 vascular plant species from 14 families, 13 lichen species from seven families, six algae taxa including both chlorophytes and cyanobacteria, and one fungal genus from the station and surrounding area. We discuss this floristic diversity in the context of the ecology of the nearby San Rafael Swell and the desert areas of Wayne and Emery counties in southeastern Utah. PMID:27350765

  1. Blue-green algae in India : a trip report

    OpenAIRE

    Roger, Pierre-Armand; Grant, I.F.; Reddy, P.M.

    1985-01-01

    Rapport de voyage et résultats d'analyses des populations d'algues et de Cyanophycées dans des sols de l'Inde et des croûtes algales. Ce rapport présente également un essai d'évaluation de l'importance de l'utilisation pratique des Cyanophycées en riziculture en Inde. (Résumé d'auteur)

  2. Effects of non-steroidal anti-inflammatory drugs on cyanobacteria and algae in laboratory strains and in natural algal assemblages.

    Science.gov (United States)

    Bácsi, István; B-Béres, Viktória; Kókai, Zsuzsanna; Gonda, Sándor; Novák, Zoltán; Nagy, Sándor Alex; Vasas, Gábor

    2016-05-01

    In recent years measurable concentrations of non-steroidal anti-inflammatory drugs (NSAIDs) have been shown in the aquatic environment as a result of increasing human consumption. Effects of five frequently used non-steroidal anti-inflammatory drugs (diclofenac, diflunisal, ibuprofen, mefenamic acid and piroxicam in 0.1 mg ml(-1) concentration) in batch cultures of cyanobacteria (Synechococcus elongatus, Microcystis aeruginosa, Cylindrospermopsis raciborskii), and eukaryotic algae (Desmodesmus communis, Haematococcus pluvialis, Cryptomonas ovata) were studied. Furthermore, the effects of the same concentrations of NSAIDs were investigated in natural algal assemblages in microcosms. According to the changes of chlorophyll-a content, unicellular cyanobacteria seemed to be more tolerant to NSAIDs than eukaryotic algae in laboratory experiments. Growth of eukaryotic algae was reduced by all drugs, the cryptomonad C. ovata was the most sensitive to NSAIDs, while the flagellated green alga H. pluvialis was more sensitive than the non-motile green alga D. communis. NSAID treatments had weaker impact in the natural assemblages dominated by cyanobacteria than in the ones dominated by eukaryotic algae, confirming the results of laboratory experiments. Diversity and number of functional groups did not change notably in cyanobacteria dominated assemblages, while they decreased significantly in eukaryotic algae dominated ones compared to controls. The results highlight that cyanobacteria (especially unicellular ones) are less sensitive to the studied, mostly hardly degradable NSAIDs, which suggest that their accumulation in water bodies may contribute to the expansion of cyanobacterial mass productions in appropriate environmental circumstances by pushing back eukaryotic algae. Thus, these contaminants require special attention during wastewater treatment and monitoring of surface waters. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. 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.

    The distribution and frequency of shell-boring green and blue-green algae in the intertidal at Goa, India were studied. The green alga Gomontia sp. and the blue green algae Hyella caespitosa Bornet et Flahault, H. gigas Lucas et Golubic...

  4. Toxicity of chlorpyrifos on some marine cyanobacteria species

    International Nuclear Information System (INIS)

    Shoaib, N.; Siddiqui, A.; Khalid, H.

    2012-01-01

    Pakistan is an agricultural country and a wide variety of pesticides are used on its cropland. Pesticides pose serious threats to the natural ecosystem. In the present study cyanobacteria (blue green algae) were used to assess the ecotoxicological effect of chlorpyrifos (organophosphate pesticide). Cyanobacteria are the base of the food web providing food resource to consumers in higher trophic level. Cyanobacteria were isolated and purified from water samples collected from Manora channel. Fast growing cultures of cyanobacteria were used to assess the toxicity of test pesticide . The Light and Dark method was used to determine the primary production of the organisms. The acute toxicity of chlorpyrifos was determined by calculating IC/sub 50/ of the test organisms. The IC/sub 50/ was found to be 0.074, 0.013, 0.08 and 0.3 ppm for Synechocystis aquatilis, Komvophoron minutum, Gloeocapsa crepidinum and Gloeocapsa sanguinea when exposed to chlorpyrifos pesticide . Laboratory experiments with cyanobacteria have demonstrated that organophosphate pesticides are potent inhibitors of photosynthesis. (author)

  5. Mass Spectral Investigation on Toxins. I. Isolation, Purification, and Characterization of Hepatotoxins from Freshwater Blue-Green Algae (Cyanobacteria) by High-Performance Liquid Chromatography and Fast Atom Bombardment Mass Spectrometric Techniques.

    Science.gov (United States)

    1986-09-01

    analysis ’" methods in environmental samples. The hepatotoxins from laboratory cultures of M. aeruginosa Strain 7820,15 Anabena flos- aguae (A. 4flos...flos- aguae S-23-g-1l (8 lug) F1 The results from the amino acid analysis using the Llqui-Mat Analyzer are listed in Table 2. The elution times of the...Runnegar, M.T.C., and Huynh, V.L. Effec- tiveness of Activated Carbon in the Removal of Algal Toxin from Potable Water Supplies: A Pilot Plant

  6. Adventures with cyanobacteria: a personal perspective

    Directory of Open Access Journals (Sweden)

    Govindjee e

    2011-07-01

    Full Text Available Cyanobacteria, or the blue-green algae as they used to be called until 1974, are the oldest oxygenic photosynthesizers. We summarize here adventures with them since the early 1960s. This includes studies on light absorption by cyanobacteria, excitation energy transfer at room temperature down to liquid helium temperature, fluorescence (kinetics as well as spectra and its relationship to photosynthesis, and afterglow (or thermoluminescence from them. Further, we summarize experiments on their two-light reaction - two-pigment system, as well as the unique role of bicarbonate (hydrogen carbonate on the electron acceptor side of their photosystem II, PSII. This review, in addition, includes a discussion on the regulation of changes in phycobilins (mostly in PSII and chlorophyll a (Chl a; mostly in photosystem I, PSI under oscillating light, on the relationship of the slow fluorescence increase (the so-called S to M rise, especially in the presence of diuron in minute time scale with the so-called state-changes, and on the possibility of limited oxygen evolution in mixotrophic PSI (minus mutants, up to 30 minutes, in the presence of glucose. We end this review with a brief discussion on the position of cyanobacteria in the evolution of photosynthetic systems.

  7. Genetic engineering of cyanobacteria as biodiesel feedstock.

    Energy Technology Data Exchange (ETDEWEB)

    Ruffing, Anne.; Trahan, Christine Alexandra; Jones, Howland D. T.

    2013-01-01

    Algal biofuels are a renewable energy source with the potential to replace conventional petroleum-based fuels, while simultaneously reducing greenhouse gas emissions. The economic feasibility of commercial algal fuel production, however, is limited by low productivity of the natural algal strains. The project described in this SAND report addresses this low algal productivity by genetically engineering cyanobacteria (i.e. blue-green algae) to produce free fatty acids as fuel precursors. The engineered strains were characterized using Sandias unique imaging capabilities along with cutting-edge RNA-seq technology. These tools are applied to identify additional genetic targets for improving fuel production in cyanobacteria. This proof-of-concept study demonstrates successful fuel production from engineered cyanobacteria, identifies potential limitations, and investigates several strategies to overcome these limitations. This project was funded from FY10-FY13 through the President Harry S. Truman Fellowship in National Security Science and Engineering, a program sponsored by the LDRD office at Sandia National Laboratories.

  8. Biodiversity of cyanobacteria and green algae on monuments in the Mediterranean Basin: an overview.

    Science.gov (United States)

    Macedo, Maria Filomena; Miller, Ana Zélia; Dionísio, Amélia; Saiz-Jimenez, Cesareo

    2009-11-01

    The presence and deteriorating action of micro-organisms on monuments and stone works of art have received considerable attention in the last few years. Knowledge of the microbial populations living on stone materials is the starting point for successful conservation treatment and control. This paper reviews the literature on cyanobacteria and chlorophyta that cause deterioration of stone cultural heritage (outdoor monuments and stone works of art) in European countries of the Mediterranean Basin. Some 45 case studies from 32 scientific papers published between 1976 and 2009 were analysed. Six lithotypes were considered: marble, limestone, travertine, dolomite, sandstone and granite. A wide range of stone monuments in the Mediterranean Basin support considerable colonization of cyanobacteria and chlorophyta, showing notable biodiversity. About 172 taxa have been described by different authors, including 37 genera of cyanobacteria and 48 genera of chlorophyta. The most widespread and commonly reported taxa on the stone cultural heritage in the Mediterranean Basin are, among cyanobacteria, Gloeocapsa, Phormidium and Chroococcus and, among chlorophyta, Chlorella, Stichococcus and Chlorococcum. The results suggest that cyanobacteria and chlorophyta colonize a wide variety of substrata and that this is related primarily to the physical characteristics of the stone surface, microclimate and environmental conditions and secondarily to the lithotype.

  9. Analysis of Mycosporine-Like Amino Acids in Selected Algae and Cyanobacteria by Hydrophilic Interaction Liquid Chromatography and a Novel MAA from the Red Alga Catenella repens

    Directory of Open Access Journals (Sweden)

    Anja Hartmann

    2015-10-01

    Full Text Available Mycosporine-like amino acids (MAAs, a group of small secondary metabolites found in algae, cyanobacteria, lichens and fungi, have become ecologically and pharmacologically relevant because of their pronounced UV-absorbing and photo-protective potential. Their analytical characterization is generally achieved by reversed phase HPLC and the compounds are often quantified based on molar extinction coefficients. As an alternative approach, in our study a fully validated hydrophilic interaction liquid chromatography (HILIC method is presented. It enables the precise quantification of several analytes with adequate retention times in a single run, and can be coupled directly to MS. Excellent linear correlation coefficients (R2 > 0.9991 were obtained, with limit of detection (LOD values ranging from 0.16 to 0.43 µg/mL. Furthermore, the assay was found to be accurate (recovery rates from 89.8% to 104.1% and precise (intra-day precision: 5.6%, inter-day precision ≤6.6%. Several algae were assayed for their content of known MAAs like porphyra-334, shinorine, and palythine. Liquid chromatography-mass spectrometry (LC-MS data indicated a novel compound in some of them, which could be isolated from the marine species Catenella repens and structurally elucidated by nuclear magnetic resonance spectroscopy (NMR as (E-3-hydroxy-2-((5-hydroxy-5-(hydroxymethyl-2-methoxy-3-((2-sulfoethylaminocyclohex-2-en-1-ylideneamino propanoic acid, a novel MAA called catenelline.

  10. Analysis of Mycosporine-Like Amino Acids in Selected Algae and Cyanobacteria by Hydrophilic Interaction Liquid Chromatography and a Novel MAA from the Red Alga Catenella repens

    Science.gov (United States)

    Hartmann, Anja; Becker, Kathrin; Karsten, Ulf; Remias, Daniel; Ganzera, Markus

    2015-01-01

    Mycosporine-like amino acids (MAAs), a group of small secondary metabolites found in algae, cyanobacteria, lichens and fungi, have become ecologically and pharmacologically relevant because of their pronounced UV-absorbing and photo-protective potential. Their analytical characterization is generally achieved by reversed phase HPLC and the compounds are often quantified based on molar extinction coefficients. As an alternative approach, in our study a fully validated hydrophilic interaction liquid chromatography (HILIC) method is presented. It enables the precise quantification of several analytes with adequate retention times in a single run, and can be coupled directly to MS. Excellent linear correlation coefficients (R2 > 0.9991) were obtained, with limit of detection (LOD) values ranging from 0.16 to 0.43 µg/mL. Furthermore, the assay was found to be accurate (recovery rates from 89.8% to 104.1%) and precise (intra-day precision: 5.6%, inter-day precision ≤6.6%). Several algae were assayed for their content of known MAAs like porphyra-334, shinorine, and palythine. Liquid chromatography-mass spectrometry (LC-MS) data indicated a novel compound in some of them, which could be isolated from the marine species Catenella repens and structurally elucidated by nuclear magnetic resonance spectroscopy (NMR) as (E)-3-hydroxy-2-((5-hydroxy-5-(hydroxymethyl)-2-methoxy-3-((2-sulfoethyl)amino)cyclohex-2-en-1-ylidene)amino) propanoic acid, a novel MAA called catenelline. PMID:26473886

  11. Report on approaches to predicting probability of cyanobacteria blooms or related indices based on nutrient inputs and other ecosystem attributes in lakes

    Science.gov (United States)

    Despite a lengthy history of research on cyanobacteria, many important questions about this diverse group of aquatic, photosynthetic “blue-green algae” remain unanswered. For example, how can we more accurately predict cyanobacteria blooms in freshwater systems? Whi...

  12. Morphology and elemental composition of recent and fossil cyanobacteria

    Science.gov (United States)

    St. Amand, Ann; Hoover, Richard B.; Jerman, Gregory A.; Coston, James; Rozanov, Alexei Y.

    2005-09-01

    Cyanobacteria (cyanophyta, cyanoprokaryota, and blue-green algae) are an ancient, diverse and abundant group of photosynthetic oxygenic microorganisms. Together with other bacteria and archaea, the cyanobacteria have been the dominant life forms on Earth for over 3.5 billion years. Cyanobacteria occur in some of our planets most extreme environments - hot springs and geysers, hypersaline and alkaline lakes, hot and cold deserts, and the polar ice caps. They occur in a wide variety of morphologies. Unlike archaea and other bacteria, which are typically classified in pure culture by their physiological, biochemical and phylogenetic properties, the cyanobacteria have historically been classified based upon their size and morphological characteristics. These include the presence or absence of heterocysts, sheath, uniseriate or multiseriate trichomes, true or false branching, arrangement of thylakoids, reproduction by akinetes, binary fission, hormogonia, fragmentation, presence/absence of motility etc. Their antiquity, distribution, structural and chemical differentiation, diversity, morphological complexity and large size compared to most other bacteria, makes the cyanobacteria ideal candidates for morphological biomarkers in returned Astromaterials. We have obtained optical (nomarski and phase contrast)/fluorescent (blue and green excitation) microscopy images using an Olympus BX60 compound microscope and Field Emission Scanning Electron Microscopy images and EDAX elemental compositions of living and fossil cyanobacteria. The S-4000 Hitachi Field Emission Scanning Electron Microscope (FESEM) has been used to investigate microfossils in freshly fractured interior surfaces of terrestrial rocks and the cells, hormogonia, sheaths and trichomes of recent filamentous cyanobacteria. We present Fluorescent and FESEM Secondary and Backscattered Electron images and associated EDAX elemental analyses of recent and fossil cyanobacteria, concentrating on representatives of the

  13. Efficacy of micro algae and cyanobacteria as a live feed for juveniles ...

    African Journals Online (AJOL)

    Administrator

    2011-09-21

    Sep 21, 2011 ... of feeding the juvenile with micro algal diets and cyanobacterial diets at the same concentrations. ... Key words: Penaeus monodon, micro algae, Synechococcus, Phormidium, ..... developments in cultivation and utilization.

  14. Ultrasonic selectivity on depressing photosynthesis of cyanobacteria and green algae probed by chlorophyll-a fluorescence transient.

    Science.gov (United States)

    Duan, Zhipeng; Tan, Xiao; Li, Niegui

    2017-10-01

    Ultrasound can inhibit cyanobacterial growth through rupturing cells, but this pathway frequently has the risk to release intercellular toxin (e.g., microcystin). Depressing photosynthesis without cell disruption may provide a new strategy to control cyanobacterial blooms using ultrasound, especially Microcystis blooms. In this work, Microcystis aeruginosa (toxic cyanobacteria) and Chlorella pyrenoidosa (typical green algae) were chosen as model microalgae to verify this hypothesis. Results showed that ultrasound has the ability to inhibit cyanobacterial photosynthesis significantly and selectively. Specifically, sonication damaged Q A , a tightly bound one-electron acceptor, and blocked electron flow at Q B , a two-electron acceptor, in the photosystem II (PSII) of M. aeruginosa when it was exposed for 60 s (35 kHz, 0.043 W/cm 3 ). Moreover, 44.8% of the reaction centers (RCs) in the PSII of M. aeruginosa were transferred into inactive ones (RC si s), and the cell concentration decreased by 32.5% after sonication for 300 s. By contrast, only 7.9% of RC si occurred in C. pyrenoidosa, and cell concentration and chlorophyll-a content reduced by 18.7% and 9.3%, respectively. Differences in both species (i.e., cell structures) might be responsible for the varying levels to sonication. This research suggests that cyanobacteria, especially Microcystis, could be controlled by ultrasound via damaging their PSIIs.

  15. Blue-green photoluminescence in MCM-41 mesoporous nanotubes

    CERN Document Server

    Shen, J L; Lui, Y L; Cheng, P W; Cheng, C F

    2003-01-01

    Different photoluminescence (PL) techniques have been used to study the blue-green emission from siliceous MCM-41 nanotubes. It was found that the intensity of the blue-green PL is enhanced by rapid thermal annealing (RTA). This enhancement is explained by the generation of twofold-coordinated Si centres and non-bridging oxygen hole centres, in line with the surface properties of MCM-41. On the basis of the analysis of the PL following RTA, polarized PL, and PL excitation, we suggest that the triplet-to-singlet transition of twofold-coordinated silicon centres is responsible for the blue-green PL in MCM-41 nanotubes. (letter to the editor)

  16. Cyanobacteria and Cyanotoxins: From Impacts on Aquatic Ecosystems and Human Health to Anticarcinogenic Effects

    Directory of Open Access Journals (Sweden)

    Giliane Zanchett

    2013-10-01

    Full Text Available Cyanobacteria or blue-green algae are among the pioneer organisms of planet Earth. They developed an efficient photosynthetic capacity and played a significant role in the evolution of the early atmosphere. Essential for the development and evolution of species, they proliferate easily in aquatic environments, primarily due to human activities. Eutrophic environments are conducive to the appearance of cyanobacterial blooms that not only affect water quality, but also produce highly toxic metabolites. Poisoning and serious chronic effects in humans, such as cancer, have been described. On the other hand, many cyanobacterial genera have been studied for their toxins with anticancer potential in human cell lines, generating promising results for future research toward controlling human adenocarcinomas. This review presents the knowledge that has evolved on the topic of toxins produced by cyanobacteria, ranging from their negative impacts to their benefits.

  17. Cyanobacteria and cyanotoxins: from impacts on aquatic ecosystems and human health to anticarcinogenic effects.

    Science.gov (United States)

    Zanchett, Giliane; Oliveira-Filho, Eduardo C

    2013-10-23

    Cyanobacteria or blue-green algae are among the pioneer organisms of planet Earth. They developed an efficient photosynthetic capacity and played a significant role in the evolution of the early atmosphere. Essential for the development and evolution of species, they proliferate easily in aquatic environments, primarily due to human activities. Eutrophic environments are conducive to the appearance of cyanobacterial blooms that not only affect water quality, but also produce highly toxic metabolites. Poisoning and serious chronic effects in humans, such as cancer, have been described. On the other hand, many cyanobacterial genera have been studied for their toxins with anticancer potential in human cell lines, generating promising results for future research toward controlling human adenocarcinomas. This review presents the knowledge that has evolved on the topic of toxins produced by cyanobacteria, ranging from their negative impacts to their benefits.

  18. Cyanobacteria and Cyanotoxins: From Impacts on Aquatic Ecosystems and Human Health to Anticarcinogenic Effects

    Science.gov (United States)

    Zanchett, Giliane; Oliveira-Filho, Eduardo C.

    2013-01-01

    Cyanobacteria or blue-green algae are among the pioneer organisms of planet Earth. They developed an efficient photosynthetic capacity and played a significant role in the evolution of the early atmosphere. Essential for the development and evolution of species, they proliferate easily in aquatic environments, primarily due to human activities. Eutrophic environments are conducive to the appearance of cyanobacterial blooms that not only affect water quality, but also produce highly toxic metabolites. Poisoning and serious chronic effects in humans, such as cancer, have been described. On the other hand, many cyanobacterial genera have been studied for their toxins with anticancer potential in human cell lines, generating promising results for future research toward controlling human adenocarcinomas. This review presents the knowledge that has evolved on the topic of toxins produced by cyanobacteria, ranging from their negative impacts to their benefits. PMID:24152991

  19. Selection of microalgae and cyanobacteria strains for bicarbonate-based integrated carbon capture and algae production system.

    Science.gov (United States)

    Chi, Zhanyou; Elloy, Farah; Xie, Yuxiao; Hu, Yucai; Chen, Shulin

    2014-01-01

    Using microalgae to capture CO2 from flue gas is an ideal way to reduce CO2 emission, but this is challenged by the high cost of carbon capture and transportation. To address this problem, a bicarbonate-based integrated carbon capture and algae production system (BICCAPS) has been proposed, in which bicarbonate is used for algae culture, and the regenerated carbonate from this process can be used to capture more CO2. High-concentration bicarbonate is obligate for the BICCAPS. Thus, different strains of microalgae and cyanobacteria were tested in this study for their capability to grow in high-concentration NaHCO3. The highest NaHCO3 concentrations they are tolerant to were determined as 0.30 M for Synechocystis sp. PCC6803, 0.60 M for Cyanothece sp., 0.10 M for Chlorella sorokiniana, 0.60 M for Dunaliella salina, and 0.30 M for Dunaliella viridis and Dunaliella primolecta. In further study, biomass production from culture of D. primolecta in an Erlenmeyer flask with either 0.30 M NaHCO3 or 2 % CO2 bubbling was compared, and no significant difference was detected. This indicates BICCAPS can reach the same biomass productivity as regular CO2 bubbling culture, and it is promising for future application.

  20. Water pollution and cyanobacteria's variation of rivers surrounding southern Taihu Lake, China.

    Science.gov (United States)

    Sun, Mingyang; Huang, Linglin; Tan, Lisha; Yang, Zhe; Baig, Shams Ali; Sheng, Tiantian; Zhu, Hong; Xu, Xinhua

    2013-05-01

    The water quality and cyanobacterial variation of rivers surrounding southern Taihu Lake, China were purposively monitored from 2008 to 2010. Trophic level index (TLI) was used to evaluate the trophic levels of southern Taihu Lake. Results showed a considerable decline in the monitored data compared with 2007, and the data showed downward trends year after year. The TLI decreased from 55.6 to 51.3, which implied that southern Taihu Lake was mildly eutrophic. The water quality and cyanobacterial variation indicated a positive response to the adopted control measures in the southern Taihu Lake basin, but the intra- and inter-annual variability was still quite varied. High concentrations of nitrogen and phosphorus typically lead to algae outbreaks, however, the cyanobacteria growth may result in a decline of the concentration of nitrogen and phosphorus. Temperature and other weather conditions are also important factors for algae outbreaks; the risk of blue-green algal blooms still persists.

  1. A Rapid and Reproducible Genomic DNA Extraction Protocol for Sequence-Based Identification of Archaea, Bacteria, Cyanobacteria, Diatoms, Fungi, and Green Algae

    OpenAIRE

    Farkhondeh Saba; Moslem Papizadeh; Javad Khansha; Mahshid Sedghi; Mehrnoosh Rasooli; Mohammad Ali Amoozegar; Mohammad Reza Soudi; Seyed Abolhassan Shahzadeh Fazeli

    2016-01-01

    Background:  Sequence-based identification of various microorganisms including Archaea, Bacteria, Cyanobacteria, Diatoms, Fungi, and green algae necessitates an efficient and reproducible genome extraction procedure though which a pure template DNA is yielded and it can be used in polymerase chain reactions (PCR). Considering the fact that DNA extraction from these microorganisms is time consuming and laborious, we developed and standardized a safe, rapid and inexpensive miniprep protocol. Me...

  2. Cyanobacteria and Algae Blooms: Review of Health and Environmental Data from the Harmful Algal Bloom-Related Illness Surveillance System (HABISS) 2007–2011

    Science.gov (United States)

    Backer, Lorraine C.; Manassaram-Baptiste, Deana; LePrell, Rebecca; Bolton, Birgit

    2015-01-01

    Algae and cyanobacteria are present in all aquatic environments. We do not have a good sense of the extent of human and animal exposures to cyanobacteria or their toxins, nor do we understand the public health impacts from acute exposures associated with recreational activities or chronic exposures associated with drinking water. We describe the Harmful Algal Bloom-related Illness Surveillance System (HABISS) and summarize the collected reports describing bloom events and associated adverse human and animal health events. For the period of 2007–2011, Departments of Health and/or Environment from 11 states funded by the National Center for Environmental Health (NCEH), Centers for Disease Control and Prevention contributed reports for 4534 events. For 2007, states contributed 173 reports from historical data. The states participating in the HABISS program built response capacity through targeted public outreach and prevention activities, including supporting routine cyanobacteria monitoring for public recreation waters. During 2007–2010, states used monitoring data to support196 public health advisories or beach closures. The information recorded in HABISS and the application of these data to develop a wide range of public health prevention and response activities indicate that cyanobacteria and algae blooms are an environmental public health issue that needs continuing attention. PMID:25826054

  3. Development of suitable photobioreactors for CO{sub 2} sequestration addressing global warming using green algae and cyanobacteria

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, K.; Dasgupta, C.N.; Nayak, B.; Lindblad, P.; Das, D. [Indian Institute of Technology, Kharagpur (India)

    2011-04-15

    CO{sub 2} sequestration by cyanobacteria and green algae are receiving increased attention in alleviating the impact of increasing CO{sub 2} in the atmosphere. They, in addition to CO{sub 2} capture, can produce renewable energy carriers such as carbon free energy hydrogen, bioethanol, biodiesel and other valuable biomolecules. Biological fixation of CO{sub 2} are greatly affected by the characteristics of the microbial strains, their tolerance to temperature and the CO{sub 2} present in the flue gas including SOx, NOx. However, there are additional factors like the availability of light, pH, O{sub 2}, removal, suitable design of the photobioreactor, culture density and the proper agitation of the reactor that will affect significantly the CO{sub 2} sequestration process. Present paper deals with the photobioreactors of different geometry available for biomass production. It also focuses on the hybrid types of reactors (integrating two reactors) which can be used for overcoming the bottlenecks of a single photobioreactor.

  4. Unraveling algae and cyanobacteria biodiversity in bromeliad phytotelmata in different vegetation formations in Bahia State, Northeastern Brazil

    Directory of Open Access Journals (Sweden)

    Geraldo José Peixoto Ramos

    2018-06-01

    Full Text Available ABSTRACT Knowledge of algal and cyanobacterial diversity of phytotelmata remains poorly-known, especially for bromeliads from different vegetation formations. We investigated the microalgae communities of four species of tank bromeliads from different vegetation formations in Bahia State, Northeast Brazil, highlighting the composition, richness and diversity of taxa. Sampling of water stored in bromeliads was carried out quarterly between 2014 and 2016, and abiotic variables and morphometric attributes of bromeliads were measured. A total of 89 taxa of algae and cyanobacteria were recorded for the four bromeliad species studied. The microalgae communities of the phytotelmata varied among vegetation formations, with one tank bromeliad, Alcantarea nahoumii, with more complex architecture (higher number of leaves and thus more cavities, being distinguished by its high species richness (73 taxa. The bromeliads exhibited little similarity in species composition, with only one species (Phacus polytrophos occurring in all four species. Throughout the entire sampling period, classes with higher species richness, especially due to A. nahoumii, were Zygnematophyceae, Cyanophyceae and Chlorophyceae, which accounted for about 80 % of all species inventoried. Our results contribute to the knowledge of microalga communities of bromeliad phytotelmata in Brazil with regard to species richness and composition, as well as significant environmental characteristics.

  5. 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

  6. Inhibition of the growth of cyanobacteria during the recruitment stage in Lake Taihu.

    Science.gov (United States)

    Lu, Yaping; Wang, Jin; Zhang, Xiaoqian; Kong, Fanxiang

    2016-03-01

    Microcystis is the dominant algal bloom genus in Lake Taihu. Thus, controlling the recruitment and growth of Microcystis is the most crucial aspect of solving the problem of algal blooms. Different concentrations (0.025, 0.05, and 0.1 g L(-1)) of tea extract were used to treat barrels of lake water at the recruitment stage of cyanobacteria. There was an inhibitory effect on algal growth in all treatment groups. The inhibitory effect on cyanobacteria was stronger than on other algae. The metabolic activity of cells in the treatment groups was significantly enhanced compared to the control, as an adaptation to the stress caused by tea polyphenols. The photosynthetic activity diminished in the treatment groups and was barely detected in the 0.05 and 0.1 g L(-1) treatments. The levels of reactive oxygen species increased substantially in treated cells with the algal cells experiencing oxidative damage. The effect of tea on zooplankton was also studied. The number of Bosmina fatalis individuals did not change significantly in the 0.025 and 0.05 g L(-1) treatments. These results suggested that the application of tea extracts, during the recruitment stage of blue-green algae, suppressed the recruitment and growth of cyanobacteria, thus offering the potential to prevent cyanobacterial blooms.

  7. A proposal for further integration of the cyanobacteria under the Bacteriological Code.

    Science.gov (United States)

    Oren, Aharon

    2004-09-01

    This taxonomic note reviews the present status of the nomenclature of the cyanobacteria under the Bacteriological Code. No more than 13 names of cyanobacterial species have been proposed so far in the International Journal of Systematic and Evolutionary Microbiology (IJSEM)/International Journal of Systematic Bacteriology (IJSB), and of these only five are validly published. The cyanobacteria (Cyanophyta, blue-green algae) are also named under the Botanical Code, and the dual nomenclature system causes considerable confusion. This note calls for a more intense involvement of the International Committee on Systematics of Prokaryotes (ICSP), its Judicial Commission and its Subcommittee on the Taxonomy of Photosynthetic Prokaryotes in the nomenclature of the cyanobacteria under the Bacteriological Code. The establishment of minimal standards for the description of new species and genera should be encouraged in a way that will be acceptable to the botanical authorities as well. This should be followed by the publication of an 'Approved List of Names of Cyanobacteria' in IJSEM. The ultimate goal is to achieve a consensus nomenclature that is acceptable both to bacteriologists and to botanists, anticipating the future implementation of a universal 'Biocode' that would regulate the nomenclature of all organisms living on Earth.

  8. The role of algal organic matter in the separation of algae and cyanobacteria using the novel "Posi" - Dissolved air flotation process.

    Science.gov (United States)

    Hanumanth Rao, Narasinga Rao; Yap, Russell; Whittaker, Michael; Stuetz, Richard M; Jefferson, Bruce; Peirson, William L; Granville, Anthony M; Henderson, Rita K

    2018-03-01

    Algae and cyanobacteria frequently require separation from liquid media in both water treatment and algae culturing for biotechnology applications. The effectiveness of cell separation using a novel dissolved air flotation process that incorporates positively charged bubbles (PosiDAF) has recently been of interest but has been shown to be dependent on the algae or cyanobacteria species tested. Previously, it was hypothesised that algal organic matter (AOM) could be impacting the separation efficiency. Hence, this study investigates the influence of AOM on cell separation using PosiDAF, in which bubbles are modified using a commercially available cationic polyelectrolyte poly(N, N-diallyl-N,N-dimethylammonium chloride) (PDADMAC). The separation of Chlorella vulgaris CS-42/7, Mychonastes homosphaera CS-556/01 and two strains of Microcystis aeruginosa (CS-564/01 and CS-555/1), all of which have similar cell morphology but different AOM character, was investigated. By testing the cell separation in the presence and absence of AOM, it was determined that AOM enhanced cell separation for all the strains but to different extents depending on the quantity and composition of carbohydrates and proteins in the AOM. By extracting AOM from the strain for which optimal separation was observed and adding it to the others, cell separation improved from 90%. This was attributed to elevated levels of acidic carbohydrates as well as glycoprotein-carbohydrate conjugations, which in turn were related to the nature and quantity of proteins and carbohydrates present in the AOM. Therefore, it was concluded that process optimisation requires an in-depth understanding of the AOM and its components. If culturing algae for biotechnology applications, this indicates that strain selection is not only important with respect to high value product content, but also for cell separation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. 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 ...

  10. Cyanobacteria toxins in the Salton Sea.

    Science.gov (United States)

    Carmichael, Wayne W; Li, RenHui

    2006-04-19

    The Salton Sea (SS) is the largest inland body of water in California: surface area 980 km2, volume 7.3 million acre-feet, 58 km long, 14-22 km wide, maximum depth 15 m. Located in the southeastern Sonoran desert of California, it is 85 m below sea level at its lowest point. It was formed between 1905 and 1907 from heavy river flows of the Colorado River. Since its formation, it has attracted both people and wildlife, including flocks of migratory birds that have made the Salton Sea a critical stopover on the Pacific flyway. Over the past 15 years wintering populations of eared grebe (Podiceps nigricollis) at the Salton Sea, have experienced over 200,000 mortalities. The cause of these large die-offs remains unknown. The unique environmental conditions of the Salton Sea, including salinities from brackish freshwater at river inlets to hypersaline conditions, extreme daily summer temperatures (>38 degrees C), and high nutrient loading from rivers and agricultural drainage favor eutrophic conditions that encourage algal blooms throughout the year. A significant component of these algal blooms are the prokaryotic group - the Cyanophyta or blue-green algae (also called Cyanobacteria). Since many Cyanobacteria produce toxins (the cyanotoxins) it became important to evaluate their presence and to determine if they are a contributing factor in eared-grebe mortalities at the Salton Sea. From November 1999 to April 2001, 247 water and sediment samples were received for phytoplankton identification and cyanotoxin analyses. Immunoassay (ELISA) screening of these samples found that eighty five percent of all water samples contained low but detectable levels of the potent cyclic peptide liver toxin called microcystins. Isolation and identification of cyanobacteria isolates showed that the picoplanktonic Synechococcus and the benthic filamentous Oscillatoria were dominant. Both organisms were found to produce microcystins dominated by microcystin-LR and YR. A laboratory strain

  11. Some of the dominant cyanobacteria and algae populating the aquatic and hydro-terrestrial habitats of Petuniabukta Bay in Svalbard in the Arctic; Niektore dominantne cyanobakterie a riasy osidlujuce akvaticke a hydroterestricke biotopy zatoky Petuniabukta na Svalbarde v Arktide

    Energy Technology Data Exchange (ETDEWEB)

    Raabova, L; Kovacik, L [Univerzita Komenskeho v Bratislave, Prirodovedecka fakulta, Katedra botaniky, 81102 Bratislava (Slovakia); Elster, J [Centrum polarni ekologie, Prirodovedecka fakulta, Jihoceska Universita, 37005 Ceske Budejovice (Czech Republic)

    2012-04-25

    This is fycologic research of the Svalbard, which is a summary term for all islands situated between 10 grad to 30 grad E and 74 grad to 81 grad latitude in the European part of the Arctic. Three selected sites within the bay Petuniabukta (78 grad 40' NL, 16 grad 27' E) at the end of the Gulf Billefjorden, located in the central part of the largest island of Svalbard were studied. Collection took place in June 2011 and we recorded totally more than 40 kinds of algae and cyanobacteria. Algae were the most abundant species. From cyanobacteria there was a predominance of filamentous Phormidium autumnale, from algae the representatives of genera Monoraphidium sp. div. and Scenedesmus sp. div. These are only partial results as a part of a more wider conceived research of these phototrophic micro-organisms in this area. (authors)

  12. Visualization of channels connecting cells in filamentous nitrogen-fixing cyanobacteria.

    Science.gov (United States)

    Omairi-Nasser, Amin; Haselkorn, Robert; Austin, Jotham

    2014-07-01

    Cyanobacteria, formerly called blue-green algae, are abundant bacteria that carry out green plant photosynthesis, fixing CO2 and generating O2. Many species can also fix N2 when reduced nitrogen sources are scarce. Many studies imply the existence of intracellular communicating channels in filamentous cyanobacteria, in particular, the nitrogen-fixing species. In a species such as Anabaena, growth in nitrogen-depleted medium, in which ∼10% of the cells differentiate into anaerobic factories for nitrogen fixation (heterocysts), requires the transport of amino acids from heterocysts to vegetative cells, and reciprocally, the transport of sugar from vegetative cells to heterocysts. Convincing physical evidence for such channels has been slim. Using improved preservation of structure by high-pressure rapid freezing of samples for electron microscopy, coupled with high-resolution 3D tomography, it has been possible to visualize and measure the dimensions of channels that breach the peptidoglycan between vegetative cells and between heterocysts and vegetative cells. The channels appear to be straight tubes, 21 nm long and 14 nm in diameter for the latter and 12 nm long and 12 nm in diameter for the former.-Omairi-Nasser, A., Haselkorn, R., Austin, J. II. Visualization of channels connecting cells in filamentous nitrogen-fixing cyanobacteria. © FASEB.

  13. Fluorescent minerals - A potential source of UV protection and visible light for the growth of green algae and cyanobacteria in extreme cosmic environments

    Science.gov (United States)

    Omairi, Tareq; Wainwright, Milton

    2015-07-01

    We propose that green algae (Chlorella variabilis and Dunaliella tertiolecta) and cyanobacteria (Synechococcus elongatus and Nostoc commune) can grow inside fluorescent rock minerals which convert damaging UV light to visible light, thereby allowing these organisms to survive and thrive in UV-rich environments without (or with limited) visible light, which would otherwise be inimical to them. The four microorganisms were incubated inside fluorescent rocks composed of fluorite, calcite and pyrite. The resultant growth was then measured following exposure to UV radiation, with the use of optical density and measurement of chlorophyll concentration. Results show that the microorganisms were shielded from harmful UV in these semi-transparent rocks, while at the same time benefiting from the fact that the minerals converted UV to visible light; this have been shown by a statistically significant increase in their growth, which although lower than when the cells were incubated in sunlight, was significantly higher than in controls incubated in the dark.

  14. Blue-Green Colour Categorisation in Mandarin-English Speakers

    Directory of Open Access Journals (Sweden)

    Emily Joanne Hird

    2012-05-01

    Full Text Available Observers are faster to detect a target among a set of distracters if the targets and distracters come from different colour categories. This cross-boundary advantage seems to be limited to the right visual field, which is consistent with the dominance of the left hemisphere for language processing. Here we study whether a similiar visual field advantage is found in Mandarin, a language which uses a logographic system. Forty late Mandarin-English bilinguals performed a blue-green colour categorisation task, in a blocked design, in their first language (L1: Mandarin or second language (L2: English. Eleven colour singletons ranging from blue to green were presented for 160ms, randomly in the left visual field (LVF or in the right visual field (RVF. We find that reaction times at the colour boundary were on average about 100 ms shorter in the LVF compared to the RVF, but only when the task was preformed in Mandarin as opposed to English. The apparent discrepancy with previous findings is conceivably due to the script nature of two languages: Mandarin logographic characters are analysed visuo-orthographically in the right fusiform gyrus [Guo and Burgund 2010, Brain Lang 115].

  15. Efficiency of using green algae as biological controllers against toxic ...

    African Journals Online (AJOL)

    Efficiency of using green algae as biological controllers against toxic algal taxa in cultured ... of two green algal species as biological control of the growth of toxic blue-green algae. ... African Journal of Aquatic Science 2014, 39(4): 443–450 ...

  16. 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.

  17. The Glaucophyta: the blue-green plants in a nutshell

    Directory of Open Access Journals (Sweden)

    Christopher Jackson

    2015-07-01

    Full Text Available The Glaucophyta is one of the three major lineages of photosynthetic eukaryotes, together with viridiplants and red algae, united in the presumed monophyletic supergroup Archaeplastida. Glaucophytes constitute a key algal lineage to investigate both the origin of primary plastids and the evolution of algae and plants. Glaucophyte plastids possess exceptional characteristics retained from their cyanobacterial ancestor: phycobilisome antennas, a vestigial peptidoglycan wall, and carboxysome-like bodies. These latter two traits are unique among the Archaeplastida and have been suggested as evidence that the glaucophytes diverged earliest during the diversification of this supergroup. Our knowledge of glaucophytes is limited compared to viridiplants and red algae, and this has restricted our capacity to untangle the early evolution of the Archaeplastida. However, in recent years novel genomic and functional data are increasing our understanding of glaucophyte biology. Diverse comparative studies using information from the nuclear genome of Cyanophora paradoxa and recent transcriptomic data from other glaucophyte species provide support for the common origin of Archaeplastida. Molecular and ultrastructural studies have revealed previously unrecognized diversity in the genera Cyanophora and Glaucocystis. Overall, a series of recent findings are modifying our perspective of glaucophyte diversity and providing fresh approaches to investigate the basic biology of this rare algal group in detail.

  18. Fluorescent minerals--A potential source of UV protection and visible light for the growth of green algae and cyanobacteria in extreme cosmic environments.

    Science.gov (United States)

    Omairi, Tareq; Wainwright, Milton

    2015-07-01

    We propose that green algae (Chlorella variabilis and Dunaliella tertiolecta) and cyanobacteria (Synechococcus elongatus and Nostoc commune) can grow inside fluorescent rock minerals which convert damaging UV light to visible light, thereby allowing these organisms to survive and thrive in UV-rich environments without (or with limited) visible light, which would otherwise be inimical to them. The four microorganisms were incubated inside fluorescent rocks composed of fluorite, calcite and pyrite. The resultant growth was then measured following exposure to UV radiation, with the use of optical density and measurement of chlorophyll concentration. Results show that the microorganisms were shielded from harmful UV in these semi-transparent rocks, while at the same time benefiting from the fact that the minerals converted UV to visible light; this have been shown by a statistically significant increase in their growth, which although lower than when the cells were incubated in sunlight, was significantly higher than in controls incubated in the dark. Copyright © 2015 The Committee on Space Research (COSPAR). Published by Elsevier Ltd. All rights reserved.

  19. A Rapid and Reproducible Genomic DNA Extraction Protocol for Sequence-Based Identification of Archaea, Bacteria, Cyanobacteria, Diatoms, Fungi, and Green Algae

    Directory of Open Access Journals (Sweden)

    Farkhondeh Saba

    2017-01-01

    Full Text Available Background:  Sequence-based identification of various microorganisms including Archaea, Bacteria, Cyanobacteria, Diatoms, Fungi, and green algae necessitates an efficient and reproducible genome extraction procedure though which a pure template DNA is yielded and it can be used in polymerase chain reactions (PCR. Considering the fact that DNA extraction from these microorganisms is time consuming and laborious, we developed and standardized a safe, rapid and inexpensive miniprep protocol. Methods:  According to our results, amplification of various genomic regions including SSU, LSU, ITS, β-tubulin, actin, RPB2, and EF-1 resulted in a reproducible and efficient DNA extraction from a wide range of microorganisms yielding adequate pure genomic material for reproducible PCR-amplifications. Results:   This method relies on a temporary shock of increased concentrations of detergent which can be applied concomitant with multiple freeze-thaws to yield sufficient amount of DNA for PCR amplification of multiple or single fragments(s of the genome. As an advantage, the recipe seems very flexible, thus, various optional steps can be included depending on the samples used.Conclusion:   Having the needed flexibility in each step, this protocol is applicable on a very wide range of samples. Hence, various steps can be included depending on the desired quantity and quality.

  20. A Rapid and Reproducible Genomic DNA Extraction Protocol for Sequence-Based Identification of Archaea, Bacteria, Cyanobacteria, Diatoms, Fungi, and Green Algae

    Directory of Open Access Journals (Sweden)

    Farkhondeh Saba

    2016-09-01

    Full Text Available Background:  Sequence-based identification of various microorganisms including Archaea, Bacteria, Cyanobacteria, Diatoms, Fungi, and green algae necessitates an efficient and reproducible genome extraction procedure though which a pure template DNA is yielded and it can be used in polymerase chain reactions (PCR. Considering the fact that DNA extraction from these microorganisms is time consuming and laborious, we developed and standardized a safe, rapid and inexpensive miniprep protocol. Methods:  According to our results, amplification of various genomic regions including SSU, LSU, ITS, β-tubulin, actin, RPB2, and EF-1 resulted in a reproducible and efficient DNA extraction from a wide range of microorganisms yielding adequate pure genomic material for reproducible PCR-amplifications. Results:   This method relies on a temporary shock of increased concentrations of detergent which can be applied concomitant with multiple freeze-thaws to yield sufficient amount of DNA for PCR amplification of multiple or single fragments(s of the genome. As an advantage, the recipe seems very flexible, thus, various optional steps can be included depending on the samples used.Conclusion:   Having the needed flexibility in each step, this protocol is applicable on a very wide range of samples. Hence, various steps can be included depending on the desired quantity and quality.

  1. Gamma-ray resistance of the blue-green alga, Synechocystis

    International Nuclear Information System (INIS)

    Gilet, Roland; Girard, Genevieve; Santier, Simone; Ozenda, Paul

    1980-01-01

    The radioresistance of this organism is high: the survival curves can be described by D 0 values between 60 and 85 Gy, and n between 8 and 2,400. In spite of the long shoulder, the dose fractionation does not show any repair of sublethal damage. Keeping the cells in a quiescent phase after irradiation enables the repair of potentially lethal damage [fr

  2. Solution Structure of Reduced Plastocyanin from the Blue-Green Alga Anabaena Variabilis

    DEFF Research Database (Denmark)

    Led, J.J.; Badsberg, U.; Jørgensen, A.M.

    1996-01-01

    from those of other plastocyanins (+1 vs -9 +/- 1 at pH greater than or equal to 7). The most striking feature of the A.v. PCu structure is the absence of the beta-turn, formed at the remote site by residues (58)-(61) in most higher plant plastocyanins. The displacement caused by the absence...... of this turn is compensated for by an extension of the small helix [from Ala53(51) to Ser60(58) in A.v. PCu] found in other plastocyanins. Moreover, the extra residues of A.v. PCu from Pro77 to Asp79 form an appended loop. These two features allow A.v. PCu to retain almost the same global fold as observed...

  3. Pathophysiology and Toxicokinetic Studies of Blue-Green Algae Intoxication in the Swine Model

    Science.gov (United States)

    1989-09-26

    In that study a ratio of L� of toxin to CTR infused into similar in situ rat gut loop preparations ameliorated the toxicoses and the liver weights...that had been produced and extracted from laboratory grown Anabaena flos- aguae NCR-525-17, paraoxon, or a control solution. Each of the 5 treatments was...Carmichael, W. W. (1987) Anatoxin-a(s), an 3 anticholinesterase from the cyanobacterium Anabaena flos- aguae NRC-525-17. Toxicon 25:1221. 3 Matsunaga, S

  4. Pathophysiology and Toxicokinetic Studies of Blue-Green Algae Intoxication in the Swine Model

    Science.gov (United States)

    1986-11-21

    given one hour apart in order to avoid excessive distension of the rumen . The dry weight dosage selected was similar to that which was experimentally...dehydrated. Ruminal atony and mild bloat developed. The three cows that first vent down had low pretreatment blood calcium concentrations of 6.4, 7.5 and...responsive, and weak. The rumen contraction rate slowed from one contraction per minute (predosing) to one contraction every three minutes. The

  5. UV-induced developmental abnormalities in the filamentous blue-green alga Nostoc linckia

    International Nuclear Information System (INIS)

    Tiwari, D.N.

    1978-01-01

    Germinating spores of Nostoc linckia showed higher resistance against UV-irradiation compared to resting spores, maximal resistance being attained more rapidly in the presence of ammonium nitrogen. UV-irradiated germinating spores on further growth formed colonies consisting of abnormally large and spheroidal cells under non-photoreactivating conditions. The formation and fate of these abnormal cells was followed in detail in a mutant clone (M-5) raised from such a colony. Many of these cells formed spores which on return to growth-conducdive conditions germinated giving rise to different types of germlings from the abnormals which in certain cases proved lethal. The possibility of a transient polyenergidic and/or heterozygous state of these 'giant' cells has been discussed. (author)

  6. CYANOBACTERIA OF THE GENUS PROCHLOROTHRIX

    Directory of Open Access Journals (Sweden)

    Alexander Vasilievich Pinevich

    2012-05-01

    Full Text Available Green cyanobacteria are distinguished from blue-green ones by the possession of a chlorophyll-containing light harvesting antenna. Three genera of green cyanobacteria, namely Acaryochloris, Prochlorococcus and Prochloron, are unicellular and of marine habitat; Prochlorococcus marinus attracts most attention due to its outstanding role in prime productivity. The fourth genus, Prochlorothrix, is represented by filamentous freshwater strains. Unlike the rest of green cyanobacteria, Prochlorothrix is paradoxically rare: it has been isolated from two European locations only. Taking into account fluctuating blooms, morphological resemblance with Planktothrix and Pseudanabaena, and unsuccessful enrichment of Prochlorothrix, the preferred strategy of search for this cyanobacterium is based on PCR with natural DNA and specific primers. This approach already demonstrates a broader distribution of Prochlorothrix: marker genes have been found in at least two additional locations. Despite the growing evidence for naturally occurring Prochlorothrix, there are only a few cultivated strains, and only one of them (PCC 9006 is claimed to be axenic. In multixenic cultures, Prochlorothrix is accompanied by heterotrophic bacteria, indicating a consortium-type association. The genus Prochlorothrix includes two species: P. hollandica and P. scandica based on distinctions in genomic DNA, cell size, temperature optimum, and fatty acid composition of membrane lipids. In this short review, the properties of cyanobacteria of the genus Prochlorothrix are described, and the evolutionary scenario of green cyanobacteria, especially taking into account their role in the origin of simple chloroplast is given.

  7. Blue-green luminescent CdZnSeS nanocrystals synthesized with activated alkyl thiol

    International Nuclear Information System (INIS)

    Xia Xing; Liu Zuli; Du Guihuan; Li Yuebin; Ma Ming; Yao Kailun

    2012-01-01

    Semiconductor nanocrystals with blue-green luminescence are potentially useful in various applications, but the preparation has not been easy compared to regular semiconductor nanocrystals with emission in the orange-red range. In this research alloyed CdZnSeS nanocrystals with luminescence covering the wavelength range from 430 to 560 nm are obtained by a one-step method with the assistance of alkyl thiol compound 1-dodecanethiol, which serves both as the sulfur source and surface ligand. The luminescence of CdZnSeS nanocrystals can be tuned from blue to green by altering the Cd:Zn molar ratio. Besides, the amount of 1-dodecanethiol in the reaction mixture can influence the emission wavelength by restricting the growth of nanocrystals. The dual control of both particle composition and size has enabled the tuning of luminescence to cover the blue-green spectral window. This research presents a convenient method to synthesize nanocrystals with tunable blue-green emission; these materials can be useful in advanced technologies such as photovoltaics, lighting and display. - Highlights: → Obtained blue-green luminescent nanocrystals by a one-step process. → Alkyl thiol used as a sulfur source and a surface stabilizer to control particle size. → Luminescence color of NCs could be easily tuned by changing their composition and particle size simultaneously.

  8. EPG waveforms of blue green sharpshooter: impedance and voltage level effects on stylet probing

    Science.gov (United States)

    Blue-green sharpshooter (BGSS), Graphocephala atropunctata, is a native California vector of Xylella fastidiosa (Xf) a foregut-borne bacterium that is the causal agent of Pierce’s disease in grapevines. A 3rd-generation, AC-DC electropenetrograph (EPG) was used to record probing behaviors of adult B...

  9. Effects of herbivore exclusion and nutrient enrichment on coral reef macroalgae and cyanobacteria

    Science.gov (United States)

    Thacker, R.; Ginsburg, D.; Paul, V.

    2001-05-01

    Although phase shifts on coral reefs from coral-dominated to algal-dominated communities have been attributed to the effects of increased nutrient availability due to eutrophication and reduced herbivore abundance due to overfishing and disease, these factors have rarely been manipulated simultaneously. In addition, few studies have considered the effects of these factors on benthic, filamentous cyanobacteria (blue-green algae) as well as macroalgae. We used a combination of herbivore-exclusion cages and nutrient enrichment to manipulate herbivore abundance and nutrient availability, and measured the impacts of these treatments on macroalgal and cyanobacterial community structure. In the absence of cages, surface cover of the cyanobacterium Tolypothrix sp. decreased, while surface cover of the cyanobacteria Oscillatoria spp. increased. Cyanobacterial cover decreased in partial cages, and Tolypothrix sp. cover decreased further in full cages. Lower cyanobacterial cover and biomass were correlated with higher macroalgal cover and biomass. Dictyota bartayresiana dominated the partial cages, while Padina tenuis and Tolypiocladia glomerulata recruited into the full cages. Palatability assays demonstrated that herbivore-exclusion shifted macroalgal species composition from relatively unpalatable to relatively palatable species. Nutrient enrichment interacted with herbivore exclusion to increase the change in cover of D. bartayresiana in the uncaged and fully caged plots, but did not affect the final biomass of D. bartayresiana among treatments. Nutrient enrichment did not significantly affect the cover or biomass of any other taxa. These results stress the critical role of herbivory in determining coral reef community structure and suggest that the relative palatabilities of dominant algae, as well as algal growth responses to nutrient enrichment, will determine the potential for phase shifts to algal-dominated communities.

  10. Developmental stages of nostocalean cyanobacteria Rivularia haematites forming in stromatolites in Sujsky peatland in Rajecka valley; Vyvinove stadia nostokalnej cyanobakterie Rivularia haematites tvoriacej stromatolity v Sujskom raselinisku v Rajeckej doline

    Energy Technology Data Exchange (ETDEWEB)

    Balazova, T. [Univerzita Komenskeho v Bratislave, Prirodovedecka fakulta, Katedra botaniky, 81102 Bratislava (Slovakia); Hindak, F. [Slovenska akademia vied, Botanicky ustav, 84523 Bratislava (Slovakia)

    2013-04-16

    In a swampy-rivulet in Sujske raselinisko (Sujsky peatland), Central Slovakia, the nostocalean cyanobacteria Rivularia haematites formed macroscopic colonies, which can be characterized as the recent stromatolites. Colonies were hemispherical up to irregularly oval, to 12 cm in diameter wide and 3 cm high, their colour was blue-green, dark green to brown. During vegetation season from May to November 2012 three steps of the filament development could be distinguished: (i) filaments blue-green, without heterocytes (early spring), (ii) filaments blue-green, with sporadically formed heterocytes (early summer), (iii) filaments ramified, always with basal heterocytes and yellow to brown stratified sheaths (summer to autumn). (authors)

  11. High-luminosity blue and blue-green gallium nitride light-emitting diodes.

    Science.gov (United States)

    Morkoç, H; Mohammad, S N

    1995-01-06

    Compact and efficient sources of blue light for full color display applications and lighting eluded and tantalized researchers for many years. Semiconductor light sources are attractive owing to their reliability and amenability to mass manufacture. However, large band gaps are required to achieve blue color. A class of compound semiconductors formed by metal nitrides, GaN and its allied compounds AIGaN and InGaN, exhibits properties well suited for not only blue and blue-green emitters, but also for ultraviolet emitters and detectors. What thwarted engineers and scientists from fabricating useful devices from these materials in the past was the poor quality of material and lack of p-type doping. Both of these obstacles have recently been overcome to the point where highluminosity blue and blue-green light-emitting diodes are now available in the marketplace.

  12. Application of blue-green and ultraviolet micro-LEDs to biological imaging and detection

    International Nuclear Information System (INIS)

    Xu, H; Zhang, J; Nurmikko, A V; Davitt, K M; Song, Y-K

    2008-01-01

    This paper reviews authors' laboratory's work on the development of nitride-based blue-green and ultraviolet microscale LED devices with particular classes of imaging and spectroscopic applications in cellular level biology. Starting from neuroscience, we illustrate the utility of blue-green micro-LEDs for voltage-sensitive dye imaging of individual neural cells, as well as their ultraviolet counterparts for photostimulation of neurons. Arrays of micro-LEDs are also shown to be useful in projecting spatiotemporal patterns of photoexcitation to study the visual system development in living animals. As another illustration of the utility of the emerging nitride microdevice technology, we demonstrate the application of UV micro-LED arrays in bio-sensing technology as the core of a real-time fluorescence spectroscopy biowarning system. (invited paper)

  13. 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.

  14. Dynamics of photosynthetic activity of cyanobacteria after gut ...

    African Journals Online (AJOL)

    African Journal of Biotechnology ... carp and goldfish, whereas there was a significant stimulation of photosynthetic activity of diatom and green algae following the depressed cyanobacteria during cultivation. The mainly stimulated eukaryotic algae species were Fragilariaceae and Scenedesmus obliquus by microscopy.

  15. Toxic cyanobacteria blooms in the Lithuanian part of the Curonian Lagoon

    Directory of Open Access Journals (Sweden)

    Artūras Razinkovas

    2009-06-01

    Full Text Available The phenomenon of cyanobacteria (blue-green algae blooms in the Baltic and the surrounding freshwater bodies has been known for several decades. The presence of cyanobacterial toxic metabolites in the Curonian Lagoon has been investigated and demonstrated for the first time in this work (2006-2007. Microcystis aeruginosa was the most common and widely distributed species in the 2006 blooms. Nodularia spumigena was present in the northern part of the Curonian Lagoon, following the intrusion of brackish water from the Baltic Sea; this is the first time that this nodularin-(NOD-producing cyanobacterium has been recorded in the lagoon. With the aid of high-performance liquid chromatography (HPLC, four microcystins (MC-LR, MC-RR, MC-LY, MC-YR and nodularin were detected in 2006. The presence of these cyanobacterial hepatotoxic cyclic peptides was additionally confirmed by enzyme-linked immunosorbent assay (ELISA and protein phosphatase inhibition assay (PP1. Microcystin-LR, the most frequent of them, was present in every sample at quite high concentrations (from <0.1 to 134.2 µg dm-3. In 2007, no cyanobacterial bloom was recorded and cyanotoxins were detected in only 4% of the investigated samples. A comparably high concentration of nodularin was detected in the northern part of the Curonian Lagoon. In one sample dimethylated MC-RR was also detected (concentration 7.5 µg dm-3.

  16. Cyanobacteria in CELSS: Growth strategies for nutritional variation and nitrogen cycling

    Science.gov (United States)

    Fry, I. V.; Packer, L.

    1990-01-01

    Cyanobacteria (blue-green algae) are versatile organisms which are capable of adjusting their cellular levels of carbohydrate, protein, and lipid in response to changes in the environment. Under stress conditions there is an imbalance between nitrogen metabolism and carbohydrate/lipid synthesis. The lesion in nitrogen assimilation is at the level of transport: the stress condition diverts energy from the active accumulation of nitrate to the extrusion of salt, and probably inhibits a cold-labile ATP'ace in the case of cold shock. Both situations affect the bioenergetic status of the cell such that the nitrogenous precursors for protein synthesis are depleted. Dispite the inhibition of protein synthesis and growth, photosynthetic reductant generation is relatively unaffected. The high O2 reductant would normally lead to photo-oxidative damage of cellular components; however, the organism copes by channeling the 'excess' reductant into carbon storage products. The increase in glycogen (28 to 35 percent dry weight increase) and the elongation of lipid fatty acid side chains (2 to 5 percent dry weight increase) at the expense of protein synthesis (25 to 34 percent dry weight decrease) results in carbohydrate, lipid and protein ratios that are closer to those required in the human diet. In addition, the selection of nitrogen fixing mutants which excrete ammonium ions present an opportunity to tailor these micro-organisms to meet the specific need for a sub-system to reverse potential loss of fixed nitrogen material.

  17. Screening of Various Herbicide Modes of Action for Selective Control of Algae Responsible for Harmful Blooms

    Science.gov (United States)

    2009-01-01

    included, Scenedesmus quadricauda and Selenastrum sp. After a two-week exposure period, all flasks were filtered. The planktonic algae were measured...activity against the various algal species tested (Figures 1 through 7). Aside from the reduction in biomass of the green alga Scenedesmus by...controls (Figures 1 through 7). Penoxsulam was highly active against the blue-greens Cylindrospermopsis and Anabaena, and the green alga Scenedesmus

  18. Bacterial control of cyanobacteria

    CSIR Research Space (South Africa)

    Ndlela, Luyanda L

    2017-08-01

    Full Text Available of biological control appears to be direct contact. • Ndlela, L. L. et al. (2016) ‘An overview of cyanobacterial bloom occurrences and research in Africa over the last decade’, Harmful Algae, 60 • Gumbo, J.R. et al. (2010) The Isolation and identification... of Predatory Bacteria from a Microcystis algal Bloom.. African Journal of Biotechnology, 9. *Special acknowledgement goes to the National Research foundation for funding this presentation Bacterial control of cyanobacteria Luyanda...

  19. Decay dynamics of blue-green luminescence in meso-porous MCM-41 nanotubes

    International Nuclear Information System (INIS)

    Lee, Y.C.; Liu, Y.L.; Wang, C.K.; Shen, J.L.; Cheng, P.W.; Cheng, C.F.; Ko, C.-H.; Lin, T.Y.

    2005-01-01

    Time-resolved photoluminescence (PL) was performed to investigate the decay of blue-green luminescence in MCM-41 nanotubes. The PL decay exhibits a clear nonexponential profile, which can be fitted by a stretched exponential function. In the temperature range from 50 to 300 K the photogenerated carriers become thermally activated with a characteristic energy of 29 meV, which is an indication of the phonon-assisted nonradiative process. The temperature dependence of the lifetime of PL decay has been explained using a model based on the radiative recombination of localized carriers and the phonon-assisted nonradiative recombination

  20. Blue-green and red photoluminescence in CaTiO3:Sm

    International Nuclear Information System (INIS)

    Figueiredo, Alberthmeiry T. de; Longo, Valeria M.; Lazaro, Sergio de; Mastelaro, Valmor R.; De Vicente, Fabio S.; Hernandes, Antonio C.; Siu Li, Maximo; Varela, Jose A.; Longo, Elson

    2007-01-01

    Blue-green and red photoluminescence (PL) emission in structurally disordered CaTiO 3 :Sm (CT:Sm) powders was observed at room temperature with laser excitation at 350.7 nm. The perovskite-like titanate CT:Sm powders prepared by a soft chemical processing at different temperatures of annealing were structurally characterized by X-ray diffraction (XRD) and X-ray absorption near-edge structure (XANES). The results indicate that the generation of the broad PL band is related to order-disorder degree in the perovskite-like structure

  1. Fish with red fluorescent eyes forage more efficiently under dim, blue-green light conditions.

    Science.gov (United States)

    Harant, Ulrike Katharina; Michiels, Nicolaas Karel

    2017-04-20

    Natural red fluorescence is particularly conspicuous in the eyes of some small, benthic, predatory fishes. Fluorescence also increases in relative efficiency with increasing depth, which has generated speculation about its possible function as a "light organ" to detect cryptic organisms under bluish light. Here we investigate whether foraging success is improved under ambient conditions that make red fluorescence stand out more, using the triplefin Tripterygion delaisi as a model system. We repeatedly presented 10 copepods to individual fish (n = 40) kept under a narrow blue-green spectrum and compared their performance with that under a broad spectrum with the same overall brightness. The experiment was repeated for two levels of brightness, a shaded one representing 0.4% of the light present at the surface and a heavily shaded one with about 0.01% of the surface brightness. Fish were 7% more successful at catching copepods under the narrow, fluorescence-friendly spectrum than under the broad spectrum. However, this effect was significant under the heavily shaded light treatment only. This outcome corroborates previous predictions that fluorescence may be an adaptation to blue-green, heavily shaded environments, which coincides with the opportunistic biology of this species that lives in the transition zone between exposed and heavily shaded microhabitats.

  2. The occurrence and removal of algae (including cyanobacteria) and their related organic compounds from source water in Vaalkop Dam with conventional and advanced drinking water treatment processes

    OpenAIRE

    Swanepoel, A; Du Preez, HH; Cloete, N

    2017-01-01

    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 Vaalkop is replenished during low-rainfall periods. These blooms during the summer months are associated with the production of cyanotoxins and taste and odour compounds such as geosm...

  3. Light adaptation of the unicellular red alga, Cyanidioschyzon merolae, probed by time-resolved fluorescence spectroscopy.

    Science.gov (United States)

    Ueno, Yoshifumi; Aikawa, Shimpei; Kondo, Akihiko; Akimoto, Seiji

    2015-08-01

    Photosynthetic organisms change the quantity and/or quality of their pigment-protein complexes and the interactions among these complexes in response to light conditions. In the present study, we analyzed light adaptation of the unicellular red alga Cyanidioschyzon merolae, whose pigment composition is similar to that of cyanobacteria because its phycobilisomes (PBS) lack phycoerythrin. C. merolae were grown under different light qualities, and their responses were measured by steady-state absorption, steady-state fluorescence, and picosecond time-resolved fluorescence spectroscopies. Cells were cultivated under four monochromatic light-emitting diodes (blue, green, yellow, and red), and changes in pigment composition and energy transfer were observed. Cells grown under blue and green light increased their relative phycocyanin levels compared with cells cultured under white light. Energy-transfer processes to photosystem I (PSI) were sensitive to yellow and red light. The contribution of direct energy transfer from PBS to PSI increased only under yellow light, while red light induced a reduction in energy transfer from photosystem II to PSI and an increase in energy transfer from light-harvesting chlorophyll protein complex I to PSI. Differences in pigment composition, growth, and energy transfer under different light qualities are discussed.

  4. The origin of blue-green window and the propagation of radiation in ocean waters

    Science.gov (United States)

    Reghunath, A. T.; Venkataramanan, V.; Suviseshamuthu, D. Victor; Krishnamohan, R.; Prasad, B. Raghavendra

    1991-01-01

    A review of the present knowledge about the origin of blue-green window in the attenuation spectrum of ocean waters is presented. The various physical mechanisms which contribute to the formation of the window are dealt separately and discussed. The typical values of attenuation coefficient arising out of the various processes are compiled to obtain the total beam attenuation coefficient. These values are then compared with measured values of attenuation coefficient for ocean waters collected from Arabian sea and Bay of Bengal. The region of minimum attenuation in pure particle-free sea water is found to be at 450 to 500 nm. It is shown that in the presence of suspended particles and chlorophyll, the window shifts to longer wavelength side. Some suggestions for future work in this area are also given in the concluding section.

  5. Microscopic origin of the fast blue-green luminescence of chemically synthesized non-oxidized silicon quantum dots

    NARCIS (Netherlands)

    Dohnalova, K.; Fucikova, A.; Umesh, C.P.; Humpolickova, J.; Paulusse, Jos Marie Johannes; Valenta, J.; Zuilhof, H.

    2012-01-01

    The microscopic origin of the bright nanosecond blue-green photoluminescence (PL), frequently reported for synthesized organically terminated Si quantum dots (Si-QDs), has not been fully resolved, hampering potential applications of this interesting material. Here a comprehensive study of the PL

  6. Microscopic Origin of the Fast Blue-Green Luminescence from Chemically Synthesized Non-Oxidized Silicon Quantum Dots

    NARCIS (Netherlands)

    Dohnalová, K.; Gregorkiewicz, T.; Fucíková, A.; Valenta, J.; Umesh, C.; Paulusse, J.M.J.; Zuilhof, H.; Humpolícková, J.; Hof, van M.

    2012-01-01

    The microscopic origin of the bright nanosecond blue-green photoluminescence (PL), frequently reported for synthesized organically terminated Si quantum dots (Si-QDs), has not been fully resolved, hampering potential applications of this interesting material. Here a comprehensive study of the PL

  7. Ba3(P1−xMnxO4)2 : Blue/green inorganic materials based on ...

    Indian Academy of Sciences (India)

    ‡Chemical Science and Technology Division, National Institute for Interdisciplinary Science and Technology ... We describe a blue/green inorganic material, Ba3(P1−xMnxO4)2 (I) based on tetrahedral MnO3−. 4 .... the synthesis at 600–950.

  8. Solution Structure of Reduced Plastocyanin from the Blue-green Alga Anabaena Variabilis

    DEFF Research Database (Denmark)

    Badsberg, Ulla; Jørgensen, Anne Marie M.; Gesmar, Henrik

    1996-01-01

    of other plastocyanins (+1 vs -9 +/- 1 at pH > or = 7). The most striking feature of the A.v. PCu structure is the absence of the beta-turn, formed at the remote site by residues (58)-(61) in most higher plant plastocyanins. The displacement caused by the absence of this turn is compensated...

  9. Anti-cancer effects of blue-green alga Spirulina platensis, a natural source of bilirubin-like tetrapyrrolic compounds

    Czech Academy of Sciences Publication Activity Database

    Koníčková, R.; Vaňková, K.; Vaníková, J.; Váňová, K.; Muchová, L.; Subhanová, I.; Zadinová, M.; Zelenka, Jaroslav; Dvořák, Aleš; Kolář, Michal; Strnad, Hynek; Rimpelová, S.; Ruml, T.; Wong, R.J.; Vítek, L.

    2014-01-01

    Roč. 13, č. 2 (2014), s. 273-283 ISSN 1665-2681 Institutional support: RVO:67985823 ; RVO:68378050 Keywords : bilirubin * chlorophyll * heme oxygenase * phycocyanin * phycocyanobilin * Spirulina platensis * tetrapyrroles Subject RIV: FD - Oncology ; Hematology Impact factor: 2.065, year: 2014

  10. Effects of some inorganic elements on nitrogen-fixation in blue-green algae and some ecological aspects of pollution

    Energy Technology Data Exchange (ETDEWEB)

    Henriksson, L.E.; DaSilva, E.J.

    1978-01-01

    Nitrogen-fixation by two species of Nostoc, one of them a lichen phycobiont, was generally stimulated by low concentrations of arsenic, cadmium, nickel, lead, palladium, and zinc. Higher concentrations (0.025 to 0.125 ppM) of arsenic, nickel, and palladium were also stimulatory; however, higher concentrations of cadmium, lead, and zinc tended to inhibit fixation. With the exception of palladium and zinc at low concentrations these six tested elements tended to inhibit nitrogen-fixation in Chlorogloea fritschii and Westiellopsis sp.

  11. On the occurrence of blooms of blue-green algae and the associated oceanographic conditions in the Northern Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Jayaraman, R.

    the organism utilizes all the available nutrients from the environment, preventing the growth and proliferation of the more useful `producer' plankton such as diatoms and dinoflagellates An explanation has been attempted on the basis of "exclusion principle...

  12. Green roof and storm water management policies: monitoring experiments on the ENPC Blue Green Wave

    Science.gov (United States)

    Versini, Pierre-Antoine; Gires, Auguste; Fitton, George; Tchiguirinskaia, Ioulia; Schertzer, Daniel

    2015-04-01

    Currently widespread in new urban projects, green roofs have shown a positive impact on urban runoff at the building/parcel scale. Nevertheless, there is no specific policy promoting their implementation neither in Europe nor in France. Moreover they are not taken into account (and usually considered as an impervious area) in the sizing of a retention basin for instance. An interesting example is located in the heart of the Paris-East Cluster for Science and Technology (Champs-sur-Marne, France). Since 2013 a large (1 ha) wavy-form vegetated roof (called bleu green wave) is implemented. Green roof area and impervious areas are connected to a large retention basin, which has been oversized. The blue green wave represents a pioneering site where an initially amenity (decorative) design project has been transformed into a research oriented one. Several measurement campaigns have been conducted to investigate and better understand the hydrological behaviour of such a structure. Rainfall, humidity, wind velocity, water content and temperature have been particularly studied. The data collected are used for several purposes: (i) characterize the spatio-temporal variability of the green roof response, (ii) calibrate and validate a specific model simulating its hydrological behavior. Based on monitoring and modeling results, green roof performances will be quantified. It will be possible to estimate how they can reduce stormwater runoff and how these performances can vary in space and in time depending on green roof configuration, rainfall event characteristics and antecedent conditions. These quantified impacts will be related to regulation rules established by stormwater managers in order to connect the parcel to the sewer network. In the particular case of the building of a retention basin, the integration of green roof in the sizing of the basin will be studied. This work is funded by the European Blue Green Dream project (http://bgd.org.uk/, funded by Climate

  13. Dinosaur origin of egg color: oviraptors laid blue-green eggs.

    Science.gov (United States)

    Wiemann, Jasmina; Yang, Tzu-Ruei; Sander, Philipp N; Schneider, Marion; Engeser, Marianne; Kath-Schorr, Stephanie; Müller, Christa E; Sander, P Martin

    2017-01-01

    reconstruction of blue-green eggs for oviraptors. According to the sexual signaling hypothesis, the reconstructed blue-green eggs support the origin of previously hypothesized avian paternal care in oviraptorid dinosaurs. Preserved dinosaur egg color not only pushes the current limits of the vertebrate molecular and associated soft tissue fossil record, but also provides a perspective on the potential application of this unexplored paleontological resource.

  14. Dinosaur origin of egg color: oviraptors laid blue-green eggs

    Directory of Open Access Journals (Sweden)

    Jasmina Wiemann

    2017-08-01

    with our reconstruction of blue-green eggs for oviraptors. According to the sexual signaling hypothesis, the reconstructed blue-green eggs support the origin of previously hypothesized avian paternal care in oviraptorid dinosaurs. Preserved dinosaur egg color not only pushes the current limits of the vertebrate molecular and associated soft tissue fossil record, but also provides a perspective on the potential application of this unexplored paleontological resource.

  15. Cyanobacteria in Coral Reef Ecosystems: A Review

    Directory of Open Access Journals (Sweden)

    L. Charpy

    2012-01-01

    Full Text Available Cyanobacteria have dominated marine environments and have been reef builders on Earth for more than three million years (myr. Cyanobacteria still play an essential role in modern coral reef ecosystems by forming a major component of epiphytic, epilithic, and endolithic communities as well as of microbial mats. Cyanobacteria are grazed by reef organisms and also provide nitrogen to the coral reef ecosystems through nitrogen fixation. Recently, new unicellular cyanobacteria that express nitrogenase were found in the open ocean and in coral reef lagoons. Furthermore, cyanobacteria are important in calcification and decalcification. All limestone surfaces have a layer of boring algae in which cyanobacteria often play a dominant role. Cyanobacterial symbioses are abundant in coral reefs; the most common hosts are sponges and ascidians. Cyanobacteria use tactics beyond space occupation to inhibit coral recruitment. Cyanobacteria can also form pathogenic microbial consortia in association with other microbes on living coral tissues, causing coral tissue lysis and death, and considerable declines in coral reefs. In deep lagoons, coccoid cyanobacteria are abundant and are grazed by ciliates, heteroflagellates, and the benthic coral reef community. Cyanobacteria produce metabolites that act as attractants for some species and deterrents for some grazers of the reef communities.

  16. Electron transfer in silicon-bridged adjacent chromophores: the source for blue-green emission.

    Science.gov (United States)

    Bayda, Malgorzata; Angulo, Gonzalo; Hug, Gordon L; Ludwiczak, Monika; Karolczak, Jerzy; Koput, Jacek; Dobkowski, Jacek; Marciniak, Bronislaw

    2017-05-10

    Si-Bridged chromophores have been proposed as sources for blue-green emission in several technological applications. The origin of this dual emission is to be found in an internal charge transfer reaction. The current work is an attempt to describe the details of these processes in these kinds of substances, and to design a molecular architecture to improve their performance. Nuclear motions essential for intramolecular charge transfer (ICT) can involve processes from twisted internal moieties to dielectric relaxation of the solvent. To address these issues, we studied ICT between adjacent chromophores in a molecular compound containing N-isopropylcarbazole (CBL) and 1,4-divinylbenzene (DVB) linked by a dimethylsilylene bridge. In nonpolar solvents emission arises from the local excited state (LE) of carbazole whereas in solvents of higher polarity dual emission was detected (LE + ICT). The CT character of the additional emission band was concluded from the linear dependence of the fluorescence maxima on solvent polarity. Electron transfer from CBL to DVB resulted in a large excited-state dipole moment (37.3 D) as determined from a solvatochromic plot and DFT calculations. Steady-state and picosecond time-resolved fluorescence experiments in butyronitrile (293-173 K) showed that the ICT excited state arises from the LE state of carbazole. These results were analyzed and found to be in accordance with an adiabatic version of Marcus theory including solvent relaxation.

  17. [Contribution of blue-green pigments to hemolytic activity of Pseudomonas aeruginosa cultural fluid].

    Science.gov (United States)

    Pyzh, A É; Nikandrov, V N

    2011-01-01

    To assess the contribution of blue-green pigments of Pseudomonas aeruginosa to hemolytic activity of its cultural fluid. MATERIALS AND METHODS. Eight hospital strains and reference strain ATCC 15442 were used. Growth dynamics of strains as well as features of accumulation of hemolytic and phospholipase activity were studied. Purified samples of pyoverdin and pyocyanin were extracted by gel-chromatography and chloroform extraction methods. Hemolytic and lecitinase activities of the samples as well as effect of active oxygen scavengers and chelating agents on these activities were studied. Dynamics of accumulation of hemolytic activity significantly differed from that of phospholipase activity when strains were grown in liquid medium. Chromatographic separation of the pigments from cultural fluid supernatants sharply reduced its hemolytic activity. Purified samples of pyoverdin and pyocyanin were capable to lyse erythrocytes and chicken egg lecitin. These characteristics of the pigments were inhibited by nitroblue tetrazolium and sensitive to chelating agents. Conclusion. Pyoverdin and pyocyanin of pathogenic strains of P. aeruginosa are capable to lyse erythrocytes and suspension of purified chicken egg lecitin, they contribute to total hemolytic activity of pathogenic strains of Pseudomonas, which is not determined only by phospholipase C produced by microorganism. Lytic activity of the pigments is blocked by nitroblue tetrazolium and susceptible to some chelating agents. Apparently, this activity is mediated by superoxide radical and determined by presence of metals with transient valence in pigments' molecules.

  18. Decision Network for Blue Green Solutions to Influence Policy Impact Assessments

    Science.gov (United States)

    Mijic, A.; Theodoropoulos, G.; El Hattab, M. H.; Brown, K.

    2017-12-01

    Sustainable Urban Drainage Systems (SuDS) deliver ecosystems services that can potentially yield multiple benefits to the urban environment. These benefits can be achieved through optimising SUDS' integration with the local environment and water resources, creating so-called Blue Green Solutions (BGS). The BGS paradigm, however, presents several challenges, in particular quantifying the benefits and creating the scientific evidence-base that can persuade high-level decision-makers and stakeholders to implement BGS at large scale. This work presents the development of the easily implemented and tailored-made approach that allows a robust assessment of the BGS co-benefits, and can influence the types of information that are included in policy impact assessments. The Analytic Network Process approach is used to synthesise the available evidence on the co-benefits of the BGS. The approach enables mapping the interactions between individual BGS selection criteria, and creates a platform to assess the synergetic benefits that arise from components interactions. By working with Government departments and other public and private sector stakeholders, this work has produced a simple decision criteria-based network that will enable the co-benefits and trade-offs of BGS to be quantified and integrated into UK policy appraisals.

  19. The Efficacy of Blue-Green Infrastructure for Pluvial Flood Prevention under Conditions of Deep Uncertainty

    Science.gov (United States)

    Babovic, Filip; Mijic, Ana; Madani, Kaveh

    2017-04-01

    Urban areas around the world are growing in size and importance; however, cities experience elevated risks of pluvial flooding due to the prevalence of impermeable land surfaces within them. Urban planners and engineers encounter a great deal of uncertainty when planning adaptations to these flood risks, due to the interaction of multiple factors such as climate change and land use change. This leads to conditions of deep uncertainty. Blue-Green (BG) solutions utilise natural vegetation and processes to absorb and retain runoff while providing a host of other social, economic and environmental services. When utilised in conjunction with Decision Making under Deep Uncertainty (DMDU) methodologies, BG infrastructure provides a flexible and adaptable method of "no-regret" adaptation; resulting in a practical, economically efficient, and socially acceptable solution for flood risk mitigation. This work presents the methodology for analysing the impact of BG infrastructure in the context of the Adaptation Tipping Points approach to protect against pluvial flood risk in an iterative manner. An economic analysis of the adaptation pathways is also conducted in order to better inform decision-makers on the benefits and costs of the adaptation options presented. The methodology was applied to a case study in the Cranbrook Catchment in the North East of London. Our results show that BG infrastructure performs better under conditions of uncertainty than traditional grey infrastructure.

  20. Investigation of the interaction of chrome compounds with blue-green microalgae Spirulina platensis

    International Nuclear Information System (INIS)

    Mosulishvili, L.M.; Belokobyl'skij, A.I.; Kirkesali, E.I.; Frontas'eva, M.V.; Pavlov, S.S.; Aksenova, N.G.

    2002-01-01

    The interaction of CrIII with the cells of blue-green microalgae Spirulina platensis in course of cultivation in a nutrient medium loaded with corresponding chrome compounds is studied. It is shown that the rate of absorption of CrVI ions by spirulina biomass from the nutrient medium is approximately two orders of magnitude lower as compared to that of CrIII ions. At the same time the presence of CrVI in a nutrient medium is accompanied by a significant decrease in the cell growth rate and by deteriorating the quality of spirulina biomass. It is established that at endogenous insertion of CrIII into the biocomplex of spirulina no change in the valence state of chromium in the nutrient medium is observed and the natural properties of the biomass do not change. On the basis of the obtained concentration dependences, the recommended doses of CrIII in the preparation 'Cr-Spirulina' within the ranges of 30-100 μg/g as a food addition, and 200-250 μg/g for a medical preventive treatment are determined. (author)

  1. Analysis of Life Cycle within Various Strains of Cyanobacteria with a Focus on Internal Regulators & Toxin Production

    Science.gov (United States)

    Cyanobacteria are photosynthetic bacteria that exhibit some similarities to algae and can be found naturally in lakes, streams, ponds, and other surface waters. However, toxin producing cyanobacteria have become an increasing concern as growth rates have been escalating. Neverthe...

  2. effect of natural blue-green algal cells lysis on freshwater quality

    African Journals Online (AJOL)

    Compaq

    released into water due to algal cells lysis was performed by placing samples in two ... Keywords; Algae, cells lysis, Fatty acids, gas chromatography time-of-flight mass spectrometry, water quality ... Factors such as municipal and industrial.

  3. A blue/green water-based accounting framework for assessment of water security

    Science.gov (United States)

    Rodrigues, Dulce B. B.; Gupta, Hoshin V.; Mendiondo, Eduardo M.

    2014-09-01

    A comprehensive assessment of water security can incorporate several water-related concepts, while accounting for Blue and Green Water (BW and GW) types defined in accordance with the hydrological processes involved. Here we demonstrate how a quantitative analysis of provision probability and use of BW and GW can be conducted, so as to provide indicators of water scarcity and vulnerability at the basin level. To illustrate the approach, we use the Soil and Water Assessment Tool (SWAT) to model the hydrology of an agricultural basin (291 km2) within the Cantareira Water Supply System in Brazil. To provide a more comprehensive basis for decision making, we analyze the BW and GW-Footprint components against probabilistic levels (50th and 30th percentile) of freshwater availability for human activities, during a 23 year period. Several contrasting situations of BW provision are distinguished, using different hydrological-based methodologies for specifying monthly Environmental Flow Requirements (EFRs), and the risk of natural EFR violation is evaluated by use of a freshwater provision index. Our results reveal clear spatial and temporal patterns of water scarcity and vulnerability levels within the basin. Taking into account conservation targets for the basin, it appears that the more restrictive EFR methods are more appropriate than the method currently employed at the study basin. The blue/green water-based accounting framework developed here provides a useful integration of hydrologic, ecosystem and human needs information on a monthly basis, thereby improving our understanding of how and where water-related threats to human and aquatic ecosystem security can arise.

  4. Efficiency of blue-green stormwater retrofits for flood mitigation - Conclusions drawn from a case study in Malmö, Sweden.

    Science.gov (United States)

    Haghighatafshar, Salar; Nordlöf, Beatrice; Roldin, Maria; Gustafsson, Lars-Göran; la Cour Jansen, Jes; Jönsson, Karin

    2018-02-01

    Coupled one-dimensional (1D) sewer and two-dimensional (2D) overland flow hydrodynamic models were constructed to evaluate the flood mitigation efficiency of a renowned blue-green stormwater retrofit, i.e. Augustenborg, in Malmö, Sweden. Simulation results showed that the blue-green stormwater systems were effective in controlling local surface flooding in inner-city catchments, having reduced the total flooded surfaces by about 70%. However, basement flooding could still be a potential problem depending on the magnitude of the inflows through combined sewer from upstream areas. Moreover, interactions between blue-green retrofits and the surrounding pipe-system were studied. It was observed that the blue-green retrofits reduced the peak flows by approximately 80% and levelled out the runoff. This is a substantial advantage for downstream pipe-bound catchments, as they do not receive a cloudburst-equivalent runoff from the retrofitted catchment, but a reduced flow corresponding to a much milder rainfall. Blue-green retrofits are more effective if primarily implemented in the upstream areas of a pipe-bound catchment since the resulting reduced runoff and levelled out discharge would benefit the entire network lying downstream. Implementing blue-green retrofits from upstream towards downstream can be considered as a sustainable approach. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. 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.

  6. Harmful Freshwater Algal Blooms, With an Emphasis on Cyanobacteria

    Directory of Open Access Journals (Sweden)

    Hans W. Paerl

    2001-01-01

    Full Text Available Suspended algae, or phytoplankton, are the prime source of organic matter supporting food webs in freshwater ecosystems. Phytoplankton productivity is reliant on adequate nutrient supplies; however, increasing rates of nutrient supply, much of it manmade, fuels accelerating primary production or eutrophication. An obvious and problematic symptom of eutrophication is rapid growth and accumulations of phytoplankton, leading to discoloration of affected waters. These events are termed blooms. Blooms are a prime agent of water quality deterioration, including foul odors and tastes, deoxygenation of bottom waters (hypoxia and anoxia, toxicity, fish kills, and food web alterations. Toxins produced by blooms can adversely affect animal (including human health in waters used for recreational and drinking purposes. Numerous freshwater genera within the diverse phyla comprising the phytoplankton are capable of forming blooms; however, the blue-green algae (or cyanobacteria are the most notorious bloom formers. This is especially true for harmful toxic, surface-dwelling, scum-forming genera (e.g., Anabaena, Aphanizomenon, Nodularia, Microcystis and some subsurface bloom-formers (Cylindrospermopsis, Oscillatoria that are adept at exploiting nutrient-enriched conditions. They thrive in highly productive waters by being able to rapidly migrate between radiance-rich surface waters and nutrient-rich bottom waters. Furthermore, many harmful species are tolerant of extreme environmental conditions, including very high light levels, high temperatures, various degrees of desiccation, and periodic nutrient deprivation. Some of the most noxious cyanobacterial bloom genera (e.g., Anabaena, Aphanizomenon, Cylindrospermopsis, Nodularia are capable of fixing atmospheric nitrogen (N2, enabling them to periodically dominate under nitrogen-limited conditions. Cyanobacteria produce a range of organic compounds, including those that are toxic to higher-ranked consumers, from

  7. Structural Determinats Underlying Photoprotection in the Photoactive Orange Carotenoid Protein of Cyanobacteria

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Adjele; Kinney, James N.; Zwart, Petrus H.; Punginelli, Claire; D' Haene, Sandrine; Perreau, Francois; Klein, Michael G.; Kirilovsky, Diana; Kerfeld, Cheryl

    2010-04-01

    The photoprotective processes of photosynthetic organisms involve the dissipation of excess absorbed light energy as heat. Photoprotection in cyanobacteria is mechanistically distinct from that in plants; it involves the Orange Carotenoid Protein (OCP), a water-soluble protein containing a single carotenoid. The OCP is a new member of the family of blue light photoactive proteins; blue-green light triggers the OCP-mediated photoprotective response. Here we report structural and functional characterization of the wildtype and two mutant forms of the OCP, from the model organism Synechocystis PCC6803. The structural analysis provides highresolution detail of the carotenoidprotein interactions that underlie the optical properties of the OCP, unique among carotenoid-proteins in binding a single pigment per polypeptide chain. Collectively, these data implicate several key amino acids in the function of the OCP and reveal that the photoconversion and photoprotective responses of the OCP to blue-green light can be decoupled.

  8. Guidance values for microcystins in water and cyanobacterial supplement products (blue-green algal supplements): a reasonable or misguided approach?

    International Nuclear Information System (INIS)

    Dietrich, Daniel; Hoeger, Stefan

    2005-01-01

    This article reviews current scientific knowledge on the toxicity and carcinogenicity of microcystins and compares this to the guidance values proposed for microcystins in water by the World Health Organization, and for blue-green algal food supplements by the Oregon State Department of Health. The basis of the risk assessment underlying these guidance values is viewed as being critical due to overt deficiencies in the data used for its generation: (i) use of one microcystin congener only (microcystin-LR), while the other presently known nearly 80 congeners are largely disregarded, (ii) new knowledge regarding potential neuro and renal toxicity of microcystins in humans and (iii) the inadequacies of assessing realistic microcystin exposures in humans and especially in children via blue-green algal food supplements. In reiterating the state-of-the-art toxicology database on microcystins and in the light of new data on the high degree of toxin contamination of algal food supplements, this review clearly demonstrates the need for improved kinetic data of microcystins in humans and for discussion concerning uncertainty factors, which may result in a lowering of the present guidance values and an increased routine control of water bodies and food supplements for toxin contamination. Similar to the approach taken previously by authorities for dioxin or PCB risk assessment, the use of a toxin equivalent approach to the risk assessment of microcystins is proposed

  9. Layer-by-layer assembly of multicolored semiconductor quantum dots towards efficient blue, green, red and full color optical films

    International Nuclear Information System (INIS)

    Zhang Jun; Li Qian; Di Xiaowei; Liu Zhiliang; Xu Gang

    2008-01-01

    Multicolored semiconductor quantum dots have shown great promise for construction of miniaturized light-emitting diodes with compact size, low weight and cost, and high luminescent efficiency. The unique size-dependent luminescent property of quantum dots offers the feasibility of constructing single-color or full-color output light-emitting diodes with one type of material. In this paper, we have demonstrated the facile fabrication of blue-, green-, red- and full-color-emitting semiconductor quantum dot optical films via a layer-by-layer assembly technique. The optical films were constructed by alternative deposition of different colored quantum dots with a series of oppositely charged species, in particular, the new use of cationic starch on glass substrates. Semiconductor ZnSe quantum dots exhibiting blue emission were deposited for fabrication of blue-emitting optical films, while semiconductor CdTe quantum dots with green and red emission were utilized for construction of green- and red-emitting optical films. The assembly of integrated blue, green and red semiconductor quantum dots resulted in full-color-emitting optical films. The luminescent optical films showed very bright emitting colors under UV irradiation, and displayed dense, smooth and efficient luminous features, showing brighter luminescence in comparison with their corresponding quantum dot aqueous colloid solutions. The assembled optical films provide the prospect of miniaturized light-emitting-diode applications.

  10. Cyanofuels: biofuels from cyanobacteria. Reality and perspectives.

    Science.gov (United States)

    Sarsekeyeva, Fariza; Zayadan, Bolatkhan K; Usserbaeva, Aizhan; Bedbenov, Vladimir S; Sinetova, Maria A; Los, Dmitry A

    2015-08-01

    Cyanobacteria are represented by a diverse group of microorganisms that, by virtue of being a part of marine and freshwater phytoplankton, significantly contribute to the fixation of atmospheric carbon via photosynthesis. It is assumed that ancient cyanobacteria participated in the formation of earth's oil deposits. Biomass of modern cyanobacteria may be converted into bio-oil by pyrolysis. Modern cyanobacteria grow fast; they do not compete for agricultural lands and resources; they efficiently convert excessive amounts of CO2 into biomass, thus participating in both carbon fixation and organic chemical production. Many cyanobacterial species are easier to genetically manipulate than eukaryotic algae and other photosynthetic organisms. Thus, the cyanobacterial photosynthesis may be directed to produce carbohydrates, fatty acids, or alcohols as renewable sources of biofuels. Here we review the recent achievements in the developments and production of cyanofuels-biofuels produced from cyanobacterial biomass.

  11. Investigation into feed utilisation by fore-aged silver carp (Hypophthalmichthys molitrix) using double-marked algae (14C and 51Cr)

    International Nuclear Information System (INIS)

    Wessel, B.; Spittler, P.; Heerkloss, R.

    1982-01-01

    The blue-green alga Microcystis firma and two green algae, Dunaliella viridis and Chlorella vulgaris, were double-marked with 14 C and 51 Cr. The 51 Cr was used as an indicator to measure the assimilation efficiency of fore-aged silver carp for radiocarbon. The assimilation efficiency values obtained were 89.0 +- 5.43% for M. firma, 61.3 +- 15.28% for D. viridis and 91.3 +- 2.22% for C. vulgaris. (author)

  12. Photosynthetic CO{sub 2} fixation and energy production - microalgae as a main subject

    Energy Technology Data Exchange (ETDEWEB)

    Asada, Yasuo [National Inst. of Bioscience and Human-Technology, Tsukuba-shi, Ibaraki-ken (Japan)

    1993-12-31

    Research activities for application of microalgal photosynthesis to CO{sub 2} fixation in Japan are overviewed. Presenter`s studies on energy (hydrogen gas) production by cyanobacteria (blue-green algae) and photosynthetic bacteria are also introduced.

  13. Fulltext PDF

    Indian Academy of Sciences (India)

    Cyanobacteria or blue green algae are one of the most diverse groups of organisms which ... freshwater (rivers, ponds and lakes), polar caps, hot springs, alkaline ... (i) RuBisCO and carbonic anhydrases (CA) enclosed in micro- compartments ...

  14. Ecological studies on algae isolated from the effluents of an oil refinery, a fertilizer factory and a brewery

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, H D [Banarus Hindu Univ.; Bisaria, G P; Bhandari, L M; Rana, B C; Sharma, V

    1974-07-01

    Tha algal flora and physico-chemical characteristics of the effluents of the Indian Oil Refinery, Barauni; the Sindri Fertilizer Factory, Sindri; and the Mohan Meakin Brewery, Ghaziabad were studied. The studies indicate that algae can tolerate and grow in highly polluted waters. The blue-green algae, flagellates and euglenoids are mostly associated with organically rich effluents, low in dissolved oxygen, whereas waters rich in nitrogenous compounds favor the growth of green algae, e.g., Chlorella. A combination of algal and chemical characteristics may be successfully employed to evaluate the water quality of a given habitat.

  15. Microscopic origin of the fast blue-green luminescence of chemically synthesized non-oxidized silicon quantum dots.

    Science.gov (United States)

    Dohnalová, Kateřina; Fučíková, Anna; Umesh, Chinnaswamy P; Humpolíčková, Jana; Paulusse, Jos M J; Valenta, Jan; Zuilhof, Han; Hof, Martin; Gregorkiewicz, Tom

    2012-10-22

    The microscopic origin of the bright nanosecond blue-green photoluminescence (PL), frequently reported for synthesized organically terminated Si quantum dots (Si-QDs), has not been fully resolved, hampering potential applications of this interesting material. Here a comprehensive study of the PL from alkyl-terminated Si-QDs of 2-3 nm size, prepared by wet chemical synthesis is reported. Results obtained on the ensemble and those from the single nano-object level are compared, and they provide conclusive evidence that efficient and tunable emission arises due to radiative recombination of electron-hole pairs confined in the Si-QDs. This understanding paves the way towards applications of chemical synthesis for the development of Si-QDs with tunable sizes and bandgaps. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Aesthetically Pleasing Conjugated Polymer: Fullerene Blends for Blue-Green Solar Cells Via Roll-to-Roll Processing

    DEFF Research Database (Denmark)

    Amb, Chad M.; Craig, Michael R.; Koldemir, Unsal

    2012-01-01

    as a thin-film deposition technique due its convenience. We report on the significant differences between the spin-coating of laboratory solar cells and slot-die coating of a blue-green colored, low bandgap polymer (PGREEN). This is one of the first demonstrations of slot-die-coated polymer solar cells OPVs......The practical application of organic photovoltaic (OPV) cells requires high throughput printing techniques in order to attain cells with an area large enough to provide useful amounts of power. However, in the laboratory screening of new materials for OPVs, spin-coating is used almost exclusively...... not utilizing poly(3-hexylthiophene):(6,6)-phenyl-C61-butyric acid methyl ester (PCBM) blends as a light absorbing layer. Through synthetic optimization, we show that strict protocols are necessary to yield polymers which achieve consistent photovoltaic behavior. We fabricated spin-coated laboratory scale OPV...

  17. The influence of bubble populations generated under windy conditions on the blue-green light transmission in the upper ocean: An exploratory approach

    Science.gov (United States)

    Wang, Chengan; Tan, Jianyu; Lai, Qingzhi

    2016-12-01

    The “blue-green window” in the ocean plays an important role in functions such as communication between vessels, underwater target identification, and remote sensing. In this study, the transmission process of blue-green light in the upper ocean is analyzed numerically using the Monte Carlo method. First, the effect of total number of photons on the numerical results is evaluated, and the most favorable number is chosen to ensure accuracy without excessive costs for calculation. Then, the physical and mathematical models are constructed. The rough sea surface is generated under windy conditions and the transmission signals are measured in the far field. Therefore, it can be conceptualized as a 1D slab with a rough boundary surface. Under windy conditions, these bubbles form layers that are horizontally homogeneous and decay exponentially with depth under the influence of gravity. The effects of bubble populations on the process of blue-green light transmission at different wind speeds, wavelengths, angle of incidence and chlorophyll-a concentrations are studied for both air-incident and water-incident cases. The results of this study indicate that the transmission process of blue-green light is significantly influenced by bubbles under high wind-speed conditions.

  18. Butterfly wing colors : glass scales of Graphium sarpedon cause polarized iridescence and enhance blue/green pigment coloration of the wing membrane

    NARCIS (Netherlands)

    Stavenga, Doekele G.; Giraldo, Marco A.; Leertouwer, Hein L.

    2010-01-01

    The wings of the swordtail butterfly Graphium sarpedon nipponum contain the bile pigment sarpedobilin, which causes blue/green colored wing patches. Locally the bile pigment is combined with the strongly blue-absorbing carotenoid lutein, resulting in green wing patches and thus improving camouflage.

  19. Degradation of textile dyes by cyanobacteria.

    Science.gov (United States)

    Dellamatrice, Priscila Maria; Silva-Stenico, Maria Estela; Moraes, Luiz Alberto Beraldo de; Fiore, Marli Fátima; Monteiro, Regina Teresa Rosim

    Dyes are recalcitrant compounds that resist conventional biological treatments. The degradation of three textile dyes (Indigo, RBBR and Sulphur Black), and the dye-containing liquid effluent and solid waste from the Municipal Treatment Station, Americana, São Paulo, Brazil, by the cyanobacteria Anabaena flos-aquae UTCC64, Phormidium autumnale UTEX1580 and Synechococcus sp. PCC7942 was evaluated. The dye degradation efficiency of the cyanobacteria was compared with anaerobic and anaerobic-aerobic systems in terms of discolouration and toxicity evaluations. The discoloration was evaluated by absorption spectroscopy. Toxicity was measured using the organisms Hydra attenuata, the alga Selenastrum capricornutum and lettuce seeds. The three cyanobacteria showed the potential to remediate textile effluent by removing the colour and reducing the toxicity. However, the growth of cyanobacteria on sludge was slow and discoloration was not efficient. The cyanobacteria P. autumnale UTEX1580 was the only strain that completely degraded the indigo dye. An evaluation of the mutagenicity potential was performed by use of the micronucleus assay using Allium sp. No mutagenicity was observed after the treatment. Two metabolites were produced during the degradation, anthranilic acid and isatin, but toxicity did not increase after the treatment. The cyanobacteria showed the ability to degrade the dyes present in a textile effluent; therefore, they can be used in a tertiary treatment of effluents with recalcitrant compounds. Copyright © 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

  20. 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

  1. The economics of cyanobacteria-based biofuel production: challenges and opportunities

    NARCIS (Netherlands)

    Sharma, N.K.; Stal, L.J.; Sharma, N.K.; Rai, A.K.; Stal, L.J.

    2014-01-01

    In the current scenario, biofuels based on algae, including cyanobacteria, are expensive, complex to produce, and are only just entering the commercial phase in small quantities in pilot or demonstration plants. This chapter discusses the current scenario of using cyanobacteria for the production of

  2. Phycourobilin in Trichromatic Phycocyanin from Oceanic Cyanobacteria Is Formed Post-translationally by a Phycoerythrobilin Lyase-Isomerase*S⃞

    Science.gov (United States)

    Blot, Nicolas; Wu, Xian-Jun; Thomas, Jean-Claude; Zhang, Juan; Garczarek, Laurence; Böhm, Stephan; Tu, Jun-Ming; Zhou, Ming; Plöscher, Matthias; Eichacker, Lutz; Partensky, Frédéric; Scheer, Hugo; Zhao, Kai-Hong

    2009-01-01

    Most cyanobacteria harvest light with large antenna complexes called phycobilisomes. The diversity of their constituting phycobiliproteins contributes to optimize the photosynthetic capacity of these microorganisms. Phycobiliprotein biosynthesis, which involves several post-translational modifications including covalent attachment of the linear tetrapyrrole chromophores (phycobilins) to apoproteins, begins to be well understood. However, the biosynthetic pathway to the blue-green-absorbing phycourobilin (λmax ∼ 495 nm) remained unknown, although it is the major phycobilin of cyanobacteria living in oceanic areas where blue light penetrates deeply into the water column. We describe a unique trichromatic phycocyanin, R-PC V, extracted from phycobilisomes of Synechococcus sp. strain WH8102. It is evolutionarily remarkable as the only chromoprotein known so far that absorbs the whole wavelength range between 450 and 650 nm. R-PC V carries a phycourobilin chromophore on its α-subunit, and this can be considered an extreme case of adaptation to blue-green light. We also discovered the enzyme, RpcG, responsible for its biosynthesis. This monomeric enzyme catalyzes binding of the green-absorbing phycoerythrobilin at cysteine 84 with concomitant isomerization to phycourobilin. This reaction is analogous to formation of the orange-absorbing phycoviolobilin from the red-absorbing phycocyanobilin that is catalyzed by the lyase-isomerase PecE/F in some freshwater cyanobacteria. The fusion protein, RpcG, and the heterodimeric PecE/F are mutually interchangeable in a heterologous expression system in Escherichia coli. The novel R-PC V likely optimizes rod-core energy transfer in phycobilisomes and thereby adaptation of a major phytoplankton group to the blue-green light prevailing in oceanic waters. PMID:19182270

  3. Fermentation in cyanobacteria

    NARCIS (Netherlands)

    Stal, L.J.; Moezelaar, R.

    1997-01-01

    Although cyanobacteria are oxygenic phototrophic organisms, they often thrive in environments that become periodically anoxic. This is particularly the case in the dark when photosynthetic oxygen evolution does not take place. Whereas cyanobacteria generally utilize endogenous storage carbohydrate

  4. The EVNATURB project: toward an operational platform to assess Blue Green Solutions eco-systemic services in urban environment

    Science.gov (United States)

    Schertzer, D. J. M.; Versini, P. A.; Tchiguirinskaia, I.

    2017-12-01

    Urban areas are facing an expected increase in intensity and frequency of extreme weather events due to climate change. Combined with unsustainable urbanization, this should exacerbate the environmental consequences related to the water cycle as stormwater management issues, urban heat island increase and biodiversity degradation. Blue Green Solutions (BGS), such as green roofs, vegetated swales or urban ponds, appear to be particularly efficient to reduce the potential impact of new and existing urban developments with respect to these issues. Based on this statement, the French ANR EVNATURB project aims to develop a platform to assess the eco-systemic services provided by BGS and related with the previously mentioned issues. By proposing a multi-disciplinary consortium coupling monitoring, modelling and prospecting, it attempts to tackle several scientific issues currently limiting BGS wide implementation. Based on high resolution monitored sites and modelling tools, space-time variability of the related physical processes will be studied over a wide range of scales (from the material to the district scale), as well as local social-environmental stakes and constraints, to better consider the complexity of the urban environment. The EVNATURB platform developed during the project is intended for every stakeholder involved in urban development projects (planners, architects, engineering and environmental certification companies…) and will help them to implement BGS and evaluate which ones are the most appropriate for a particular project depending on its environmental objectives and constraints, and particularly for obtaining environmental certification.

  5. Growth and properties of blue/green InGaN/GaN MQWs on Si(111) substrates

    International Nuclear Information System (INIS)

    Lee, Kang Jea; Oh, Tae Su; Kim, Tae Ki; Yang, Gye Mo; Lim, Kee Young

    2005-01-01

    InGaN/GaN multiple quantum wells (MQWs) were grown on highly tensile-strained GaN films on Si(111) substrate by metalorganic chemical vapor deposition. Due to the large difference of lattice constant and thermal expansion coefficient between GaN and Si, GaN growth on Si(111) substrate usually leads to an initially high dislocation density and cracks. We demonstrate low dislocation-density and crack-free GaN films grown on Si(111) substrate by introducing an AlN/GaN strain-compensation layer and Si x N y dislocation masking layer. Blue/green-emitting InGaN/GaN MQW heterostructures have been successfully grown on Si(111) substrates. Two sets of InGaN/GaN MQWs with different In solid composition and number of pairs grown between 820 .deg. C and 900 .deg. C were studied by high-resolution X-ray diffraction and photoluminescence spectroscopy. The emission wavelengths of InGaN MQW structures were significantly dependent on growth temperature.

  6. Reverse leakage current characteristics of InGaN/GaN multiple quantum well ultraviolet/blue/green light-emitting diodes

    Science.gov (United States)

    Zhou, Shengjun; Lv, Jiajiang; Wu, Yini; Zhang, Yuan; Zheng, Chenju; Liu, Sheng

    2018-05-01

    We investigated the reverse leakage current characteristics of InGaN/GaN multiple quantum well (MQW) near-ultraviolet (NUV)/blue/green light-emitting diodes (LEDs). Experimental results showed that the NUV LED has the smallest reverse leakage current whereas the green LED has the largest. The reason is that the number of defects increases with increasing nominal indium content in InGaN/GaN MQWs. The mechanism of the reverse leakage current was analyzed by temperature-dependent current–voltage measurement and capacitance–voltage measurement. The reverse leakage currents of NUV/blue/green LEDs show similar conduction mechanisms: at low temperatures, the reverse leakage current of these LEDs is attributed to variable-range hopping (VRH) conduction; at high temperatures, the reverse leakage current of these LEDs is attributed to nearest-neighbor hopping (NNH) conduction, which is enhanced by the Poole–Frenkel effect.

  7. Blue-green eggshell coloration is not a sexually selected signal of female quality in an open-nesting polygynous passerine

    Czech Academy of Sciences Publication Activity Database

    Honza, Marcel; Požgayová, Milica; Procházka, Petr; Cherry, M. I.

    2011-01-01

    Roč. 98, č. 6 (2011), s. 493-499 ISSN 0028-1042 R&D Projects: GA AV ČR IAA600930605; GA AV ČR IAA600930903; GA MŠk LC06073 Institutional research plan: CEZ:AV0Z60930519 Keywords : Acrocephalus arundinaceus * Blue-green chroma * Egg colour * Female condition * Great reed warbler * Polygyny Subject RIV: EG - Zoology Impact factor: 2.278, year: 2011

  8. Low driving voltage blue, green, yellow, red and white organic light-emitting diodes with a simply double light-emitting structure.

    Science.gov (United States)

    Zhang, Zhensong; Yue, Shouzhen; Wu, Yukun; Yan, Pingrui; Wu, Qingyang; Qu, Dalong; Liu, Shiyong; Zhao, Yi

    2014-01-27

    Low driving voltage blue, green, yellow, red and white phosphorescent organic light-emitting diodes (OLEDs) with a common simply double emitting layer (D-EML) structure are investigated. Our OLEDs without any out-coupling schemes as well as n-doping strategies show low driving voltage, e.g. white OLED, respectively. This work demonstrates that the low driving voltages and high efficiencies can be simultaneously realized with a common simply D-EML structure.

  9. Comparison of blue-green response between transmission-mode GaAsP- and GaAs-based photocathodes grown by molecular beam epitaxy

    Science.gov (United States)

    Gang-Cheng, Jiao; Zheng-Tang, Liu; Hui, Guo; Yi-Jun, Zhang

    2016-04-01

    In order to develop the photodetector for effective blue-green response, the 18-mm-diameter vacuum image tube combined with the transmission-mode Al0.7Ga0.3As0.9 P 0.1/GaAs0.9 P 0.1 photocathode grown by molecular beam epitaxy is tentatively fabricated. A comparison of photoelectric property, spectral characteristic and performance parameter between the transmission-mode GaAsP-based and blue-extended GaAs-based photocathodes shows that the GaAsP-based photocathode possesses better absorption and higher quantum efficiency in the blue-green waveband, combined with a larger surface electron escape probability. Especially, the quantum efficiency at 532 nm for the GaAsP-based photocathode achieves as high as 59%, nearly twice that for the blue-extended GaAs-based one, which would be more conducive to the underwater range-gated imaging based on laser illumination. Moreover, the simulation results show that the favorable blue-green response can be achieved by optimizing the emission-layer thickness in a range of 0.4 μm-0.6 μm. Project supported by the National Natural Science Foundation of China (Grant No. 61301023) and the Science and Technology on Low-Light-Level Night Vision Laboratory Foundation, China (Grant No. BJ2014001).

  10. Light scattering influence in cyanobacteria suspensions inside a photobioreactor

    Science.gov (United States)

    Fanjul-Vélez, F.; Arce-Diego, J. L.

    2018-02-01

    The application of biotechnology is increasing in areas such as agriculture, biochemistry or biomedicine. Growing bacteria or algae could be beneficial for supplying fuel, drugs, food or oxygen, among other products. An adequate knowledge of biological processes is becoming essential to estimate and control products production. Cyanobacteria are particularly appropriate for producing oxygen and biomass, by consuming mainly carbon dioxide and light irradiation. These capacities could be employed to provide human subsistence in adverse environments, as basic breathing and food needs would be satisfied. Cyanobacteria growing is carried out in bioreactors. As light irradiation is quite relevant for their behavior, photobioreactors are needed. Photobioreactors are designed to supply and control the amounts of elements they need, in order to maximize growth. The adequate design of photobioreactors greatly influences production throughput. This design includes, on the optical side, optical illumination and optical measurement of cyanobacteria growth. The influence of optical scattering is fundamental for maximizing cyanobacteria growing, as long as for adequately measure this growth. In this work, optical scattering in cyanobacteria suspensions is analyzed. Optical properties of cyanobacteria and its relationship with concentration is taken into account. Several types of cyanobacteria are considered. The influence of different beam spatial profiles and irradiances is studied by a Monte Carlo approach. The results would allow the consideration of the influence of optical scattering in the detected optical signal employed for growth monitoring, as a function of cyanobacteria type and optical beam parameters.

  11. Liquid chromatographic determination of the cyanobacterial toxin beta-n-methylamino-L-alanine in algae food supplements, freshwater fish, and bottled water.

    Science.gov (United States)

    Scott, Peter M; Niedzwiadek, Barbara; Rawn, Dorothea F K; Lau, Ben P-Y

    2009-08-01

    Beta-N-Methylamino-L-alanine (BMAA) is a neurotoxin originally found in cycad seeds and now known to be produced by many species of freshwater and marine cyanobacteria. We developed a method for its determination in blue-green algae (BGA) food supplements, freshwater fish, and bottled water by using a strong cation-exchange, solid-phase extraction column for cleanup after 0.3 M trichloroacetic acid extraction of BGA supplements and fish. Bottled water was applied directly onto the solid-phase extraction column. For analysis of carbonated water, sonication and pH adjustment to 1.5 were needed. To determine protein-bound BMAA, the protein pellet left after extraction of the BGA supplement and fish was hydrolyzed by boiling with 6 M hydrochloric acid; BMAA was cleaned up on a C18 column and a strong cation-exchange, solid-phase extraction column. Determination of BMAA was by liquid chromatography of the fluorescent derivative formed with 9-fluorenylmethyl chloroformate. The method was validated by recovery experiments using spiking levels of 1.0 to 10 microg/g for BGA supplements, 0.5 to 5.0 microg/g for fish, and 0.002 microg/g for bottled water; mean recoveries were in the range of 67 to 89% for BGA supplements and fish, and 59 to 92% for bottled water. Recoveries of BMAA from spiked extracts of hydrolyzed protein from BGA supplements and fish ranged from 66 to 83%. The cleanup developed provides a useful method for surveying foods and supplements for BMAA and protein-bound BMAA.

  12. Antibacterial activities of the extracts of cyanobacteria and green ...

    African Journals Online (AJOL)

    In compliance to the recent surveys on algal species and their potentials to produce biologically active compounds, seven algal species belonging to cyanobacteria such as Spirulina platensis, Nostoc linckia, Phormidium autumnale, Tolypothrix distorta and Microcystis aeruginosa and green algae such as Chlorella vulgaris, ...

  13. Spatial Evaluation of Multiple Benefits to Encourage Multi-Functional Design of Sustainable Drainage in Blue-Green Cities

    Directory of Open Access Journals (Sweden)

    Richard Fenner

    2017-12-01

    Full Text Available Urban drainage systems that incorporate elements of green infrastructure (SuDS/GI are central features in Blue-Green and Sponge Cities. Such approaches provide effective control of stormwater management whilst generating a range of other benefits. However these benefits often occur coincidentally and are not developed or maximised in the original design. Of all the benefits that may accrue, the relevant dominant benefits relating to specific locations and socio-environmental circumstances need to be established, so that flood management functions can be co-designed with these wider benefits to ensure both are achieved during system operation. The paper reviews a number of tools which can evaluate the multiple benefits of SuDS/GI interventions in a variety of ways and introduces new concepts of benefit intensity and benefit profile. Examples of how these concepts can be applied is provided in a case study of proposed SuDS/GI assets in the central area of Newcastle; UK. Ways in which SuDS/GI features can be actively extended to develop desired relevant dominant benefits are discussed; e.g., by (i careful consideration of tree and vegetation planting to trap air pollution; (ii extending linear SuDS systems such as swales to enhance urban connectivity of green space; and (iii managing green roofs for the effective attenuation of noise or carbon sequestration. The paper concludes that more pro-active development of multiple benefits is possible through careful co-design to achieve the full extent of urban enhancement SuDS/GI schemes can offer.

  14. Changes of the laser-induced blue, green and red fluorescence signatures during greening of etiolated leaves of wheat

    International Nuclear Information System (INIS)

    Stober, F.; Lichtenthaler, H.K.

    1992-01-01

    The UV-laser-induced blue, green and red fluorescence-emission spectra were used to characterize the pigment status of etiolated leaves of wheat (Triticum aestivum L.) during a 48 h greening period under white light conditions. Upon UV-light excitation (337 nm) leaves not only show a fluorescence emission in the red spectral region between 650 and 800nm (chlorophyll fluorescence with maxima near 690nm and 735 nm), but also in the blue and green regions between 400 to 570 nm with maxima or shoulders near 450 nm (blue) and 530 nm (green). During greening of etiolated leaves the chlorophyll-fluorescence ratio F690/F735 strongly correlated with the total chlorophyll content and the ratio of the chlorophylls to the carotenoids (a+b/x+c). The ratio of the blue to the green fluorescence F450/F530 was also correlated with the total chlorophyll content and the ratio of chlorophylls to total carotenoids (a+b/x+c). Consequently, there also existed a correlation between the chlorophyll-fluorescence ratio F690/F735 and the ratio of the blue to green fluorescence F450/F530. In contrast, the ratios of the blue to red fluorescences F450/F690 and F450/F735 did not show clear relations to the pigment content of the investigated plants. The particular shape of the UV-laser-induced-fluorescence emission spectra of wheat leaves as well as the dependencies of the fluorescence ratios on the pigment content are due to a partial and differential reabsorption of the emitted fluorescences by the photosynthetic pigments

  15. 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)

  16. Antiviral lectins from red and blue-green algae show potent in vitro and in vivo activity against hepatitis C virus.

    Directory of Open Access Journals (Sweden)

    Yutaka Takebe

    Full Text Available Hepatitis C virus (HCV infection is a significant public health problem with over 170,000,000 chronic carriers and infection rates increasing worldwide. Chronic HCV infection is one of the leading causes of hepatocellular carcinoma which was estimated to result in ∼10,000 deaths in the United States in the year 2011. Current treatment options for HCV infection are limited to PEG-ylated interferon alpha (IFN-α, the nucleoside ribavirin and the recently approved HCV protease inhibitors telaprevir and boceprevir. Although showing significantly improved efficacy over the previous therapies, treatment with protease inhibitors has been shown to result in the rapid emergence of drug-resistant virus. Here we report the activity of two proteins, originally isolated from natural product extracts, which demonstrate low or sub-nanomolar in vitro activity against both genotype I and genotype II HCV. These proteins inhibit viral infectivity, binding to the HCV envelope glycoproteins E1 and E2 and block viral entry into human hepatocytes. In addition, we demonstrate that the most potent of these agents, the protein griffithsin, is readily bioavailable after subcutaneous injection and shows significant in vivo efficacy in reducing HCV viral titers in a mouse model system with engrafted human hepatocytes. These results indicate that HCV viral entry inhibitors can be an effective component of anti-HCV therapy and that these proteins should be studied further for their therapeutic potential.

  17. Isotopic studies on nitrogen fixation and nitrogen cycling in blue-green algae and azolla. Final report for the period 1985-1989

    Energy Technology Data Exchange (ETDEWEB)

    Kauser, A M; Sikander, A [Nuclear Inst. for Agriculture and Biology, Faisalabad (Pakistan)

    1990-12-31

    Under the IAEA coordination project, a series of field and pot experiments have been conducted to demonstrate the various aspects of Azolla technology as a contribution of nitrogen to the nutrition of agricultural crops, especially rice. This final report summarizes the previous experiments and gives details on the last experiments. 1 fig., 7 tabs.

  18. Isotopic studies on nitrogen fixation and nitrogen cycling in blue-green algae and azolla. Final report for the period 1985-1989

    International Nuclear Information System (INIS)

    Kauser, A.M.; Sikander, A.

    1989-01-01

    Under the IAEA coordination project, a series of field and pot experiments have been conducted to demonstrate the various aspects of Azolla technology as a contribution of nitrogen to the nutrition of agricultural crops, especially rice. This final report summarizes the previous experiments and gives details on the last experiments. 1 fig., 7 tabs

  19. Evaluation of microcystin contamination in blue-green algal dietary supplements using a protein phosphatase inhibition-based test kit.

    Science.gov (United States)

    Marsan, David W; Conrad, Stephen M; Stutts, Whitney L; Parker, Christine H; Deeds, Jonathan R

    2018-03-01

    The cyanobacterium Aphanizomenon flos-aquae (AFA), from Upper-Klamath Lake, Oregon, are used to produce blue-green algal (BGA) dietary supplements. The periodic co-occurrence of hepatotoxin-producing contaminant species prompted the Oregon Health Division to establish a limit of 1 μg/g microcystin (MC) for products sold in Oregon in 1997. At the federal level, the current good manufacturing practice (CGMP) regulations for dietary supplements require manufacturers establish a specification, and test, for limits on contaminants that may adulterate finished products. Despite this, several previous international surveys reported MC in BGA supplements in excess of 1 μg/g. The objectives of this study were (1) identify a reliable, easy to use test kit for the detection of MC in dried BGA materials and (2) use this kit to assess the occurrence of MC contamination in AFA-BGA dietary supplements in the U.S. A commercial protein phosphatase inhibition assay (PPIA), based on the enzyme PP2A, was found to have acceptable relative enzyme inhibition and accuracy for the majority of MC variants tested, including those most commonly identified in commercial samples, making the kit fit for purpose. Using the PPIA kit, 51% (26 of 51) distinct AFA-BGA products had MC ≥0.25 μg/g (the detection limit of the kit), 10 products had MC concentrations between 0.5 and 1.0 μg/g, and 4 products exceeded the limit (1.1-2.8 μg/g). LC-MS/MS confirmed PPIA results ≥0.5 μg/g and determined that MC-LA and MC-LR were the main congeners present. PPIA is a reliable method for the detection of MC contamination in dried BGA dietary supplements produced in the U.S. While the majority of AFA-BGA products contained ≥0.25 μg/g MC, most were at or below 1.0 μg/g, suggesting that manufacturers have adopted this level as a specification in these products; however, variability in recommended serving sizes prevented further analysis of consumer exposure based on the concentrations of MC

  20. Evaluation of microcystin contamination in blue-green algal dietary supplements using a protein phosphatase inhibition-based test kit

    Directory of Open Access Journals (Sweden)

    David W. Marsan

    2018-03-01

    Full Text Available The cyanobacterium Aphanizomenon flos-aquae (AFA, from Upper-Klamath Lake, Oregon, are used to produce blue-green algal (BGA dietary supplements. The periodic co-occurrence of hepatotoxin-producing contaminant species prompted the Oregon Health Division to establish a limit of 1 μg/g microcystin (MC for products sold in Oregon in 1997. At the federal level, the current good manufacturing practice (CGMP regulations for dietary supplements require manufacturers establish a specification, and test, for limits on contaminants that may adulterate finished products. Despite this, several previous international surveys reported MC in BGA supplements in excess of 1 μg/g. The objectives of this study were (1 identify a reliable, easy to use test kit for the detection of MC in dried BGA materials and (2 use this kit to assess the occurrence of MC contamination in AFA-BGA dietary supplements in the U.S. A commercial protein phosphatase inhibition assay (PPIA, based on the enzyme PP2A, was found to have acceptable relative enzyme inhibition and accuracy for the majority of MC variants tested, including those most commonly identified in commercial samples, making the kit fit for purpose. Using the PPIA kit, 51% (26 of 51 distinct AFA-BGA products had MC ≥0.25 μg/g (the detection limit of the kit, 10 products had MC concentrations between 0.5 and 1.0 μg/g, and 4 products exceeded the limit (1.1–2.8 μg/g. LC-MS/MS confirmed PPIA results ≥0.5 μg/g and determined that MC-LA and MC-LR were the main congeners present. PPIA is a reliable method for the detection of MC contamination in dried BGA dietary supplements produced in the U.S. While the majority of AFA-BGA products contained ≥0.25 μg/g MC, most were at or below 1.0 μg/g, suggesting that manufacturers have adopted this level as a specification in these products; however, variability in recommended serving sizes prevented further analysis of consumer exposure based on the concentrations of MC

  1. Soil algae

    African Journals Online (AJOL)

    Timothy Ademakinwa

    Also, the importance of algae in soil formation and soil fertility improvement cannot be over ... The presence of nitrogen fixing microalgae (Nostoc azollae) in the top soil of both vegetable ..... dung, fish food and dirty water from fish ponds on.

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

    Science.gov (United States)

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

    2007-08-04

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

  3. 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)

  4. System responses to equal doses of photosynthetically usable radiation of blue, green, and red light in the marine diatom Phaeodactylum tricornutum.

    Directory of Open Access Journals (Sweden)

    Kristin Collier Valle

    Full Text Available Due to the selective attenuation of solar light and the absorption properties of seawater and seawater constituents, free-floating photosynthetic organisms have to cope with rapid and unpredictable changes in both intensity and spectral quality. We have studied the transcriptional, metabolic and photo-physiological responses to light of different spectral quality in the marine diatom Phaeodactylum tricornutum through time-series studies of cultures exposed to equal doses of photosynthetically usable radiation of blue, green and red light. The experiments showed that short-term differences in gene expression and profiles are mainly light quality-dependent. Transcription of photosynthesis-associated nuclear genes was activated mainly through a light quality-independent mechanism likely to rely on chloroplast-to-nucleus signaling. In contrast, genes encoding proteins important for photoprotection and PSII repair were highly dependent on a blue light receptor-mediated signal. Changes in energy transfer efficiency by light-harvesting pigments were spectrally dependent; furthermore, a declining trend in photosynthetic efficiency was observed in red light. The combined results suggest that diatoms possess a light quality-dependent ability to activate photoprotection and efficient repair of photodamaged PSII. In spite of approximately equal numbers of PSII-absorbed quanta in blue, green and red light, the spectral quality of light is important for diatom responses to ambient light conditions.

  5. Meteorological effects on variation of airborne algae in Mexico

    Science.gov (United States)

    Rosas, Irma; Roy-Ocotla, Guadalupe; Mosiño, Pedro

    1989-09-01

    Sixteen species of algae were collected from 73.8 m3 of air. Eleven were obtained in Minatitlán and eleven in México City. The data show that similar diversity occurred between the two localities, in spite of the difference in altitude. This suggests that cosmopolitan airborne microorganisms might have been released from different sources. Three major algal divisions (Chlorophyta, Cyanophyta and Chrysophyta) formed the airborne algal group. Also, a large concentration of 2220 algae m-3 was found near sea-level, while lower amounts were recorded at the high altitude of México City. The genera Scenedesmus, Chlorella and Chlorococcum dominated. Striking relationships were noted between the concentration of airborne green and blue-green algae, and meteorological conditions such as rain, vapour pressure, temperature and winds for different altitudes. In Minatitlán a linear relationship was established between concentration of algae and both vapour pressure (mbar) and temperature (° C), while in México City the wind (m s-1) was associated with variations in the algal count.

  6. 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.

  7. Genetically Engineered Cyanobacteria

    Science.gov (United States)

    Zhou, Ruanbao (Inventor); Gibbons, William (Inventor)

    2015-01-01

    The disclosed embodiments provide cyanobacteria spp. that have been genetically engineered to have increased production of carbon-based products of interest. These genetically engineered hosts efficiently convert carbon dioxide and light into carbon-based products of interest such as long chained hydrocarbons. Several constructs containing polynucleotides encoding enzymes active in the metabolic pathways of cyanobacteria are disclosed. In many instances, the cyanobacteria strains have been further genetically modified to optimize production of the carbon-based products of interest. The optimization includes both up-regulation and down-regulation of particular genes.

  8. CYANOTOXINS: NEW GENERATION OF WATER CONTAMINANTS

    Science.gov (United States)

    Cyanobacteria, more commonly known as blue-green algae, are found worldwide in various aquatic environments as well as in water distribution systems (Atikovic 2003; Carmichael 1994; Madigan et al. 2003). Blooms of cyanobacteria have recently become spatially and temporally more p...

  9. The regulation of microcystin biosynthesis pathways and genetic mechanisms

    OpenAIRE

    Serap YALÇIN

    2012-01-01

    The cyanobacteria (blue-green algae), as they arecommonly named, comprise a diverse group of oxygenicphotosynthetic bacteria that inhabit a wide rangeof aquatic and terrestrial environments, and displayincredible morphological diversity. Cyanobacteriaproduce bioactive secondary metabolites, includingalkaloids, polyketides and non-ribosomal peptides, someof which are potent toxins. The common occurrenceof toxic cyanobacteria causes problems for health ofanimals and human. Cyanobacterial toxins...

  10. Morphology, ecology and phylogeny of cyanobacteria belonging to genera Nostoc and Desmonostoc in Lithuania

    OpenAIRE

    Špakaitė, Ina

    2014-01-01

    The aim of the study was to investigate the morphology, ecology and phylogeny of cyanobacteria belonging to genera Nostoc and Desmonostoc in Lithuania. The detailed research of freshwater and terrestrial Nostoc and Desmonostoc species provided new data on taxonomy, biology and ecology of these cyanobacteria and the overall diversity of algae in Lithuania. 20 Nostoc species and two intraspecific taxa, and 18 taxa to the Nostoc genus level were identified. Twelve Nostoc species and intraspecifi...

  11. Photocatalytic Cellulosic Electrospun Fibers for the Degradation of Potent Cyanobacteria Toxin Microcystin-LR

    Science.gov (United States)

    2012-01-01

    visible light activated or UV light activated), the surface area of the fiber mat, and loading solution pH all have an effect on the distribution of...photocatalysis with nanoparticles (such as titania, TiO2 ) show tremendous promise as a simple and energy efficient tech- nology for water purification and...LR (MC-LR). MC- LR is one of the most commonly found cyanobacteria toxins generated by the more frequently occurring cyanobacteria algae blooms in

  12. Cyanobacteria Index (MERIS)

    Data.gov (United States)

    U.S. Environmental Protection Agency — This dataset shows the concentration of cyanobacteria cells/ml in fresh water bodies and estuaries of the Ohio and Florida derived from 300x300 meter MEdium...

  13. 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.

  14. Extending the biosynthetic repertoires of cyanobacteria and chloroplasts

    DEFF Research Database (Denmark)

    Nielsen, Agnieszka Janina Zygadlo; Mellor, Silas Busck; Vavitsas, Konstantinos

    2016-01-01

    The chloroplasts found in plants and algae, and photosynthetic microorganisms such as cyanobacteria, are emerging hosts for sustainable production of valuable biochemicals, using only inorganic nutrients, water, CO2 and light as inputs. In the past decade, many bioengineering efforts have focused...... on metabolic engineering and synthetic biology in the chloroplast or in cyanobacteria for the production of fuels, chemicals, as well as complex, high-value bioactive molecules. Biosynthesis of all these compounds can be performed in photosynthetic organelles/organisms by heterologous expression...... of chloroplasts and cyanobacteria as biosynthetic compartments and hosts, and we estimate the production levels to be expected from photosynthetic hosts in light of the fraction of electrons and carbon that can potentially be diverted from photosynthesis. The supply of reducing power, in the form of electrons...

  15. CyanoClust: comparative genome resources of cyanobacteria and plastids.

    Science.gov (United States)

    Sasaki, Naobumi V; Sato, Naoki

    2010-01-01

    Cyanobacteria, which perform oxygen-evolving photosynthesis as do chloroplasts of plants and algae, are one of the best-studied prokaryotic phyla and one from which many representative genomes have been sequenced. Lack of a suitable comparative genomic database has been a problem in cyanobacterial genomics because many proteins involved in physiological functions such as photosynthesis and nitrogen fixation are not catalogued in commonly used databases, such as Clusters of Orthologous Proteins (COG). CyanoClust is a database of homolog groups in cyanobacteria and plastids that are produced by the program Gclust. We have developed a web-server system for the protein homology database featuring cyanobacteria and plastids. Database URL: http://cyanoclust.c.u-tokyo.ac.jp/.

  16. CyanoClust: comparative genome resources of cyanobacteria and plastids

    OpenAIRE

    Sasaki, Naobumi V.; Sato, Naoki

    2010-01-01

    Cyanobacteria, which perform oxygen-evolving photosynthesis as do chloroplasts of plants and algae, are one of the best-studied prokaryotic phyla and one from which many representative genomes have been sequenced. Lack of a suitable comparative genomic database has been a problem in cyanobacterial genomics because many proteins involved in physiological functions such as photosynthesis and nitrogen fixation are not catalogued in commonly used databases, such as Clusters of Orthologous Protein...

  17. Relative efficacy of the argon green, argon blue-green, and krypton red lasers for 10-0 nylon subconjunctival laser suture lysis.

    Science.gov (United States)

    Mudgil, A V; To, K W; Balachandran, R M; Janigian, R H; Tsiaras, W G

    1999-01-01

    To determine the optimal wavelength for subconjunctival laser suture lysis. 130 black monofilament 10-0 nylon sutures were sewn subconjunctivally into the bare sclera of enucleated rabbit globes. The lowest energy levels facilitating laser suture lysis were determined for the argon green (514.5 NM), argon blue-green (488.0 NM, 514.5 NM), and krypton red (647.1 NM) wavelengths. In addition, absorption spectroscopy was performed on the suture material and conjunctiva using the Perkin Elmer W/VIS Lambda 2 spectrometer. Krypton red produced the fewest buttonhole defects, and it was also the most efficient energy source for suture lysis (P = 0.0001) under nontenectomized conjunctiva. Absorbance spectra studies revealed peak absorbance at 628 NM for the 10-0 nylon suture material. Based on animal and absorption spectroscopy studies, krypton red may be a safer and more efficient wavelength for subconjunctival laser suture lysis.

  18. Environmental factors that influence cyanobacteria and geosmin occurrence in reservoirs

    Science.gov (United States)

    Journey, Celeste A.; Beaulieu, Karen M.; Bradley, Paul M.; Bradley, Paul M.

    2013-01-01

    Phytoplankton are small to microscopic, free-floating algae that inhabit the open water of freshwater, estuarine, and saltwater systems. In freshwater lake and reservoirs systems, which are the focus of this chapter, phytoplankton communities commonly consist of assemblages of the major taxonomic groups, including green algae, diatoms, dinoflagellates, and cyanobacteria. Cyanobacteria are a diverse group of single-celled organisms that can exist in a wide range of environments, not just open water, because of their adaptability. It is the adaptability of cyanobacteria that enables this group to dominate the phytoplankton community and even form nuisance or harmful blooms under certain environmental conditions. In fact, cyanobacteria are predicted to adapt favorably to future climate change in freshwater systems compared to other phytoplankton groups because of their tolerance to rising temperatures, enhanced vertical thermal stratification of aquatic ecosystems, and alterations in seasonal and interannual weather patterns. Understanding those environmental conditions that favor cyanobacterial dominance and bloom formation has been the focus of research throughout the world because of the concomitant production and release of nuisance and toxic cyanobacterial-derived compounds. However, the complex interaction among the physical, chemical, and biological processes within lakes, reservoirs, and large rivers often makes it difficult to identify primary environmental factors that cause the production and release of these cyanobacterial by-products.

  19. Phytoplankton diversity in the Cross River Estuary of Nigeria | Ekwu ...

    African Journals Online (AJOL)

    Bacillariophyceae (Diatom) was the most abundant phytoplankton family, constituting 71.58% of total Algal density, followed by Chlorophyceae (Green algae) with 13.84%, Cyanobacteria (Blue-green algae) with 12.69%, while Euglenophyceae (Green flagellates) and Dinophyceae (Dinoflagellates) recorded 0.88% and ...

  20. Partitioning of monomethylmercury between freshwater algae and water.

    Science.gov (United States)

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

    2001-11-01

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

  1. Toxicology of freshwater cyanobacteria.

    Science.gov (United States)

    Liyanage, H M; Arachchi, D N Magana; Abeysekara, T; Guneratne, L

    2016-07-02

    Many chemical contaminants in drinking water have been shown to cause adverse health effects in humans after prolonged exposure. Cyanobacteria are one of the most potent and diverse groups of photosynthetic prokaryotes. One key component of cyanobacterial success in the environment is the production of potent toxins as secondary metabolites, which have been responsible for numerous adverse health impacts in humans. Anthropogenic activities have led to the increase of eutrophication in freshwater bodies' worldwide, causing cyanobacterial blooms to become more frequent. The present article will discuss about harmful cyanobacteria and their toxicology with special references to microcystin, nodularin, and cylindrospermopsin.

  2. Cyanobacteria: an economic perspective

    NARCIS (Netherlands)

    Sharma, N.K.; Rai, A.K.; Stal, L.J.

    2014-01-01

    Written by leading experts in the field, Cyanobacteria: An Economic Perspective is a comprehensive edited volume covering all areas of an important field and its application to energy, medicine and agriculture. Issues related to environment, food and energy have presented serious challenge to the

  3. Ultraviolet radiation and cyanobacteria.

    Science.gov (United States)

    Rastogi, Rajesh Prasad; Sinha, Rajeshwar P; Moh, Sang Hyun; Lee, Taek Kyun; Kottuparambil, Sreejith; Kim, Youn-Jung; Rhee, Jae-Sung; Choi, Eun-Mi; Brown, Murray T; Häder, Donat-Peter; Han, Taejun

    2014-12-01

    Cyanobacteria are the dominant photosynthetic prokaryotes from an ecological, economical, or evolutionary perspective, and depend on solar energy to conduct their normal life processes. However, the marked increase in solar ultraviolet radiation (UVR) caused by the continuous depletion of the stratospheric ozone shield has fueled serious concerns about the ecological consequences for all living organisms, including cyanobacteria. UV-B radiation can damage cellular DNA and several physiological and biochemical processes in cyanobacterial cells, either directly, through its interaction with certain biomolecules that absorb in the UV range, or indirectly, with the oxidative stress exerted by reactive oxygen species. However, cyanobacteria have a long history of survival on Earth, and they predate the existence of the present ozone shield. To withstand the detrimental effects of solar UVR, these prokaryotes have evolved several lines of defense and various tolerance mechanisms, including avoidance, antioxidant production, DNA repair, protein resynthesis, programmed cell death, and the synthesis of UV-absorbing/screening compounds, such as mycosporine-like amino acids (MAAs) and scytonemin. This study critically reviews the current information on the effects of UVR on several physiological and biochemical processes of cyanobacteria and the various tolerance mechanisms they have developed. Genomic insights into the biosynthesis of MAAs and scytonemin and recent advances in our understanding of the roles of exopolysaccharides and heat shock proteins in photoprotection are also discussed. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Glycolipid biosynthesis in cyanobacteria

    International Nuclear Information System (INIS)

    Van Dusen, W.J.; Jaworski, J.G.

    1987-01-01

    The biosynthesis of monogalactosyldiacyl-glycerol (MGDG) was studied in five different cyanobacteria. Previous work has shown Anabaena variabilis to synthesize both MGDG and monoglucosyl-diacylglycerol (MG1cDG) with MG1cDG being the precursor of MGDG. They have examined four other cyanobacteria to determine if a similar relationship exists. The cyanobacteria studied were Anabaena variabilis, Chlorogloeopsis sp., Schizothrix calcicola, Anacystis nidulans, and Anacystis marina. Each were grown in liquid culture and lipids were labeled with 14 C]CO 2 for 20 min., 1.0 hr, 1.0 hr + 10 hr chase. Glycolipids were analyzed by initial separation of MGDG and MG1cDG by TLC followed by further analysis by HPLC. Complete separation of molecular species was obtained isocratically on an ODS column. All of the cyanobacteria labeled 16-C and 18-C fatty acids except for A. marina which labeled only 14-C and 16-C fatty acids. Desaturation of the fatty acids could be observed in the 1.0 hr and chase experiments. All were capable of labeling both MG1cDG and MGDG with the precursor-product relationship being observed. There does not appear to be a direct relationship between the epimerization of the sugar moiety and fatty acid desaturation

  5. Nitrogen Fixation in Cyanobacteria

    NARCIS (Netherlands)

    Stal, L.J.

    2008-01-01

    Cyanobacteria are oxygenic photosynthetic bacteria that are widespread in marine, freshwater and terrestrial environments and many of them are capable of fixing atmospheric nitrogen. But ironically, nitrogenase, the enzyme that is responsible for the reduction of N2, is extremely sensitive to O2.

  6. Photosynthetic electron transport in thylakoid preparations from two marine red algae (Rhodophyta).

    Science.gov (United States)

    Stewart, A C; Larkum, A W

    1983-01-01

    Thylakoid membrane preparations active in photosynthetic electron transport have been obtained from two marine red algae, Griffithsia monilis and Anotrichium tenue. High concentrations (0.5-1.0 M) of salts such as phosphate, citrate, succinate and tartrate stabilized functional binding of phycobilisomes to the membrane and also stabilized Photosystem II-catalysed electron-transport activity. High concentrations (1.0 M) of chloride and nitrate, or 30 mM-Tricine/NaOH buffer (pH 7.2) in the absence of salts, detached phycobilisomes and inhibited electron transport through Photosystem II. The O2-evolving system was identified as the electron-transport chain component that was inhibited under these conditions. Washing membranes with buffers containing 1.0-1.5 M-sorbitol and 5-50 mM concentrations of various salts removed the outer part of the phycobilisome but retained 30-70% of the allophycocyanin 'core' of the phycobilisome. These preparations were 30-70% active in O2 evolution compared with unwashed membranes. In the sensitivity of their O2-evolving apparatus to the composition of the medium in vitro, the red algae resembled blue-green algae and differed from other eukaryotic algae and higher plants. It is suggested that an environment of structured water may be essential for the functional integrity of Photosystem II in biliprotein-containing algae. PMID:6860312

  7. Blue-green fluorescence and visible-infrared reflectance of corn (Zea mays L.) grain for in situ field detection of nitrogen supply

    International Nuclear Information System (INIS)

    McMurtrey, J.E. III; Chappelle, E.W.; Kim, M.S.; Corp, L.A.; Daughtry, C.S.T.

    1996-01-01

    The sensing of spectral attributes of corn (Zea mays L.) grain from site specific areas of the field during the harvest process may be useful in managing agronomic inputs and production practices on those areas of the field in subsequent growing seasons. Eight levels of nitrogen (N) fertilization were applied to field grown corn at Beltsville, Maryland. These N treatments produced a range of chlorophyll levels, biomass and physiological condition in the live plant canopies. After harvest, spectra were obtained in the laboratory on whole grain samples. Fluorescence emissions were acquired from 400 to 600 nm and percent reflectance were measured in the visible (VIS) near infrared (NIR) and mid-infrared (MIR) regions from 400 nm to 2400 nm. A ultraviolet (UV) excitation band centered at 385 nm was the most effective in producing fluorescence emission differences in the blue-green region of the fluorescence spectrum with maxima centered from 430-470nm in the blue and with an intense shoulder centered at around 530-560 nm in the green region. Reflectance showed the most spectral differences in the NIR and MIR (970-2330 nm) regions

  8. Use of Blue-Green Fluorescence and Thermal Imaging in the Early Detection of Sunflower Infection by the Root Parasitic Weed Orobanche cumana Wallr.

    Science.gov (United States)

    Ortiz-Bustos, Carmen M; Pérez-Bueno, María L; Barón, Matilde; Molinero-Ruiz, Leire

    2017-01-01

    Although the impact of Orobanche cumana Wallr. on sunflower ( Helianthus annuus L.) becomes evident with emergence of broomrape shoots aboveground, infection occurs early after sowing, the host physiology being altered during underground parasite stages. Genetic resistance is the most effective control method and one of the main goals of sunflower breeding programmes. Blue-green fluorescence (BGF) and thermal imaging allow non-destructive monitoring of plant diseases, since they are sensitive to physiological disorders in plants. We analyzed the BGF emission by leaves of healthy sunflower plantlets, and we implemented BGF and thermal imaging in the detection of the infection by O. cumana during underground parasite development. Increases in BGF emission were observed in leaf pairs of healthy sunflowers during their development. Lower BGF was consistently detected in parasitized plants throughout leaf expansion and low pigment concentration was detected at final time, supporting the interpretation of a decrease in secondary metabolites upon infection. Parasite-induced stomatal closure and transpiration reduction were suggested by warmer leaves of inoculated sunflowers throughout the experiment. BGF imaging and thermography could be implemented for fast screening of sunflower breeding material. Both techniques are valuable approaches to assess the processes by which O. cumana alters physiology (secondary metabolism and photosynthesis) of sunflower.

  9. Use of Blue-Green Fluorescence and Thermal Imaging in the Early Detection of Sunflower Infection by the Root Parasitic Weed Orobanche cumana Wallr.

    Directory of Open Access Journals (Sweden)

    Carmen M. Ortiz-Bustos

    2017-05-01

    Full Text Available Although the impact of Orobanche cumana Wallr. on sunflower (Helianthus annuus L. becomes evident with emergence of broomrape shoots aboveground, infection occurs early after sowing, the host physiology being altered during underground parasite stages. Genetic resistance is the most effective control method and one of the main goals of sunflower breeding programmes. Blue-green fluorescence (BGF and thermal imaging allow non-destructive monitoring of plant diseases, since they are sensitive to physiological disorders in plants. We analyzed the BGF emission by leaves of healthy sunflower plantlets, and we implemented BGF and thermal imaging in the detection of the infection by O. cumana during underground parasite development. Increases in BGF emission were observed in leaf pairs of healthy sunflowers during their development. Lower BGF was consistently detected in parasitized plants throughout leaf expansion and low pigment concentration was detected at final time, supporting the interpretation of a decrease in secondary metabolites upon infection. Parasite-induced stomatal closure and transpiration reduction were suggested by warmer leaves of inoculated sunflowers throughout the experiment. BGF imaging and thermography could be implemented for fast screening of sunflower breeding material. Both techniques are valuable approaches to assess the processes by which O. cumana alters physiology (secondary metabolism and photosynthesis of sunflower.

  10. Presentation layer finding database of cyanobacteria and algae

    OpenAIRE

    SEMECKÝ, Jiří

    2012-01-01

    Phycological Laboratory University of South Bohemia in Czech Budejovice uses occurrence database samples. This work deals with the analysis and optimization of the existing database, designing and programming extension that allows processing points based on GPS coordinates and display them in on-line maps and georeferenced image.

  11. New lantibiotics from cyanobacteria

    OpenAIRE

    Yang, Jiahui Jr

    2016-01-01

    Lantibiotics are a subgroup of bacteriocins, produced by Gram-positive bacteria to inhibit the growth of closely related strains. They are used as food preservatives e.g. nisin, and some are in clinical trials, e.g. duramycin A and microbisporicin. Cinnamycin is a 19 amino acid lantibiotic that inhibits the growth of Gram-positive rods. Recent work suggests that cyanobacteria might be able to make variants of cinnamycin. Here I determined the product of a cinnamycin biosynthetic pathway prese...

  12. Antifungal compounds from cyanobacteria.

    Science.gov (United States)

    Shishido, Tânia K; Humisto, Anu; Jokela, Jouni; Liu, Liwei; Wahlsten, Matti; Tamrakar, Anisha; Fewer, David P; Permi, Perttu; Andreote, Ana P D; Fiore, Marli F; Sivonen, Kaarina

    2015-04-13

    Cyanobacteria are photosynthetic prokaryotes found in a range of environments. They are infamous for the production of toxins, as well as bioactive compounds, which exhibit anticancer, antimicrobial and protease inhibition activities. Cyanobacteria produce a broad range of antifungals belonging to structural classes, such as peptides, polyketides and alkaloids. Here, we tested cyanobacteria from a wide variety of environments for antifungal activity. The potent antifungal macrolide scytophycin was detected in Anabaena sp. HAN21/1, Anabaena cf. cylindrica PH133, Nostoc sp. HAN11/1 and Scytonema sp. HAN3/2. To our knowledge, this is the first description of Anabaena strains that produce scytophycins. We detected antifungal glycolipopeptide hassallidin production in Anabaena spp. BIR JV1 and HAN7/1 and in Nostoc spp. 6sf Calc and CENA 219. These strains were isolated from brackish and freshwater samples collected in Brazil, the Czech Republic and Finland. In addition, three cyanobacterial strains, Fischerella sp. CENA 298, Scytonema hofmanni PCC 7110 and Nostoc sp. N107.3, produced unidentified antifungal compounds that warrant further characterization. Interestingly, all of the strains shown to produce antifungal compounds in this study belong to Nostocales or Stigonematales cyanobacterial orders.

  13. Antifungal Compounds from Cyanobacteria

    Directory of Open Access Journals (Sweden)

    Tânia K. Shishido

    2015-04-01

    Full Text Available Cyanobacteria are photosynthetic prokaryotes found in a range of environments. They are infamous for the production of toxins, as well as bioactive compounds, which exhibit anticancer, antimicrobial and protease inhibition activities. Cyanobacteria produce a broad range of antifungals belonging to structural classes, such as peptides, polyketides and alkaloids. Here, we tested cyanobacteria from a wide variety of environments for antifungal activity. The potent antifungal macrolide scytophycin was detected in Anabaena sp. HAN21/1, Anabaena cf. cylindrica PH133, Nostoc sp. HAN11/1 and Scytonema sp. HAN3/2. To our knowledge, this is the first description of Anabaena strains that produce scytophycins. We detected antifungal glycolipopeptide hassallidin production in Anabaena spp. BIR JV1 and HAN7/1 and in Nostoc spp. 6sf Calc and CENA 219. These strains were isolated from brackish and freshwater samples collected in Brazil, the Czech Republic and Finland. In addition, three cyanobacterial strains, Fischerella sp. CENA 298, Scytonema hofmanni PCC 7110 and Nostoc sp. N107.3, produced unidentified antifungal compounds that warrant further characterization. Interestingly, all of the strains shown to produce antifungal compounds in this study belong to Nostocales or Stigonematales cyanobacterial orders.

  14. Extending the biosynthetic repertoires of cyanobacteria and chloroplasts.

    Science.gov (United States)

    Nielsen, Agnieszka Zygadlo; Mellor, Silas Busck; Vavitsas, Konstantinos; Wlodarczyk, Artur Jacek; Gnanasekaran, Thiyagarajan; Perestrello Ramos H de Jesus, Maria; King, Brian Christopher; Bakowski, Kamil; Jensen, Poul Erik

    2016-07-01

    Chloroplasts in plants and algae and photosynthetic microorganisms such as cyanobacteria are emerging hosts for sustainable production of valuable biochemicals, using only inorganic nutrients, water, CO2 and light as inputs. In the past decade, many bioengineering efforts have focused on metabolic engineering and synthetic biology in the chloroplast or in cyanobacteria for the production of fuels, chemicals and complex, high-value bioactive molecules. Biosynthesis of all these compounds can be performed in photosynthetic organelles/organisms by heterologous expression of the appropriate pathways, but this requires optimization of carbon flux and reducing power, and a thorough understanding of regulatory pathways. Secretion or storage of the compounds produced can be exploited for the isolation or confinement of the desired compounds. In this review, we explore the use of chloroplasts and cyanobacteria as biosynthetic compartments and hosts, and we estimate the levels of production to be expected from photosynthetic hosts in light of the fraction of electrons and carbon that can potentially be diverted from photosynthesis. The supply of reducing power, in the form of electrons derived from the photosynthetic light reactions, appears to be non-limiting, but redirection of the fixed carbon via precursor molecules presents a challenge. We also discuss the available synthetic biology tools and the need to expand the molecular toolbox to facilitate cellular reprogramming for increased production yields in both cyanobacteria and chloroplasts. © 2016 The Authors The Plant Journal © 2016 John Wiley & Sons Ltd.

  15. Efficient blue-green and green electroluminescent devices obtained by doping iridium complexes into hole-block material as supplementary light-emitting layer

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Liang [State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Zheng, Youxuan, E-mail: yxzheng@mail.nju.edu.cn [State Key Laboratory of Coordination Chemistry, Nanjing National Laboratory of Microstructures, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093 (China); Deng, Ruiping; Feng, Jing; Song, Mingxing; Hao, Zhaomin [State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Zhang, Hongjie, E-mail: hongjie@ciac.jl.cn [State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Zuo, Jinglin; You, Xiaozeng [State Key Laboratory of Coordination Chemistry, Nanjing National Laboratory of Microstructures, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093 (China)

    2014-04-15

    In this work, organic electroluminescent (EL) devices with dominant and supplementary light-emitting layers (EMLs) were designed to further improve the EL performances of two iridium{sup III}-based phosphorescent complexes, which have been reported to provide EL devices with slow EL efficiency roll-off. The widely used hole-block material 2,2′,2''-(1,3,5-Benzinetriyl)-tris(1-phenyl-1-H-benzimidazole) (TPBi) was selected as host material to construct the supplementary EML. Compared with single-EML devices, double-EMLs devices showed higher EL efficiencies, higher brightness, and lower operation voltage attributed to wider recombination zone and better balance of carriers. In addition, the insertion of supplementary EML is instrumental in facilitating carriers trapping, thus improving the color purity. Finally, high performance blue-green and green EL devices with maximum current efficiencies of 35.22 and 90.68 cd/A, maximum power efficiencies of 26.36 and 98.18 lm/W, and maximum brightness of 56,678 and 112,352 cd/m{sup 2}, respectively, were obtained by optimizing the doping concentrations. Such a device design strategy extends the application of a double EML device structure and provides a chance to simplify device fabrication processes. -- Highlights: • Electroluminescent devices with supplementary light-emitting layer were fabricated. • Doping concentrations and thicknesses were optimized. • Better balance of holes and electrons causes the enhanced efficiency. • Improved carrier trapping suppresses the emission of host material.

  16. DNA barcode of coastal alga ( Chlorella sorokiniana ) from Ago ...

    African Journals Online (AJOL)

    Five different loci 18S, UPA, rbcl, ITS and tufA were tested for their use as deoxyribonucleic acid (DNA) barcode in this study. Although the UPA primers were designed to amplify all phototrophic algae and cyanobacteria, UPA and 18S did not amplified at all for the genus Chlorella while ITS1, ITS2 rDNA and rbcL markers ...

  17. Evolutionary origins, molecular cloning and expression of carotenoid hydroxylases in eukaryotic photosynthetic algae

    Science.gov (United States)

    2013-01-01

    Background Xanthophylls, oxygenated derivatives of carotenes, play critical roles in photosynthetic apparatus of cyanobacteria, algae, and higher plants. Although the xanthophylls biosynthetic pathway of algae is largely unknown, it is of particular interest because they have a very complicated evolutionary history. Carotenoid hydroxylase (CHY) is an important protein that plays essential roles in xanthophylls biosynthesis. With the availability of 18 sequenced algal genomes, we performed a comprehensive comparative analysis of chy genes and explored their distribution, structure, evolution, origins, and expression. Results Overall 60 putative chy genes were identified and classified into two major subfamilies (bch and cyp97) according to their domain structures. Genes in the bch subfamily were found in 10 green algae and 1 red alga, but absent in other algae. In the phylogenetic tree, bch genes of green algae and higher plants share a common ancestor and are of non-cyanobacterial origin, whereas that of red algae is of cyanobacteria. The homologs of cyp97a/c genes were widespread only in green algae, while cyp97b paralogs were seen in most of algae. Phylogenetic analysis on cyp97 genes supported the hypothesis that cyp97b is an ancient gene originated before the formation of extant algal groups. The cyp97a gene is more closely related to cyp97c in evolution than to cyp97b. The two cyp97 genes were isolated from the green alga Haematococcus pluvialis, and transcriptional expression profiles of chy genes were observed under high light stress of different wavelength. Conclusions Green algae received a β-xanthophylls biosynthetic pathway from host organisms. Although red algae inherited the pathway from cyanobacteria during primary endosymbiosis, it remains unclear in Chromalveolates. The α-xanthophylls biosynthetic pathway is a common feature in green algae and higher plants. The origination of cyp97a/c is most likely due to gene duplication before divergence of

  18. Evolutionary origins, molecular cloning and expression of carotenoid hydroxylases in eukaryotic photosynthetic algae.

    Science.gov (United States)

    Cui, Hongli; Yu, Xiaona; Wang, Yan; Cui, Yulin; Li, Xueqin; Liu, Zhaopu; Qin, Song

    2013-07-08

    Xanthophylls, oxygenated derivatives of carotenes, play critical roles in photosynthetic apparatus of cyanobacteria, algae, and higher plants. Although the xanthophylls biosynthetic pathway of algae is largely unknown, it is of particular interest because they have a very complicated evolutionary history. Carotenoid hydroxylase (CHY) is an important protein that plays essential roles in xanthophylls biosynthesis. With the availability of 18 sequenced algal genomes, we performed a comprehensive comparative analysis of chy genes and explored their distribution, structure, evolution, origins, and expression. Overall 60 putative chy genes were identified and classified into two major subfamilies (bch and cyp97) according to their domain structures. Genes in the bch subfamily were found in 10 green algae and 1 red alga, but absent in other algae. In the phylogenetic tree, bch genes of green algae and higher plants share a common ancestor and are of non-cyanobacterial origin, whereas that of red algae is of cyanobacteria. The homologs of cyp97a/c genes were widespread only in green algae, while cyp97b paralogs were seen in most of algae. Phylogenetic analysis on cyp97 genes supported the hypothesis that cyp97b is an ancient gene originated before the formation of extant algal groups. The cyp97a gene is more closely related to cyp97c in evolution than to cyp97b. The two cyp97 genes were isolated from the green alga Haematococcus pluvialis, and transcriptional expression profiles of chy genes were observed under high light stress of different wavelength. Green algae received a β-xanthophylls biosynthetic pathway from host organisms. Although red algae inherited the pathway from cyanobacteria during primary endosymbiosis, it remains unclear in Chromalveolates. The α-xanthophylls biosynthetic pathway is a common feature in green algae and higher plants. The origination of cyp97a/c is most likely due to gene duplication before divergence of green algae and higher plants

  19. 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.

  20. Antimicrobial-resistant faecal organisms in algae products marketed as health supplements

    LENUS (Irish Health Repository)

    2017-09-01

    Dietary supplements are increasingly popular in Irish society. One of these is blue-green algae which is used with a variety health benefits in mind. A batch of Chlorella powder was found to be contaminated with Salmonella species in Ireland in 2015. This prompted additional testing of a total of 8 samples of three different products (Chlorella, Spirulina and Super Greens), for other faecal flora and antimicrobial resistance in any bacteria isolated. All 8 samples cultured enteric flora such as Enterococci, Enterobacteriaceae and Clostridium species. Antimicrobial susceptibility testing revealed one isolate with extended-spectrum β-lactamase (ESBL) activity and one with carbapenemase activity. Clinicians caring for vulnerable patients should be aware of the potential risk of exposure to antimicrobial resistant bacteria associated with these products

  1. Assessment of cyanobacteria impact on bathing water quality in Poland

    Directory of Open Access Journals (Sweden)

    Krzysztof Skotak

    2012-12-01

    Full Text Available Introduction: Quality of bathing water is of key importance for bathers’ health, mainly due to the fact, that each year millions of people use bathing sites as places for recreation and sport activities. Most of the bathing sites are of adequate quality of water, but still there are cases of health risk because bathing water is polluted. One of the main health risk factor in bathing water are cyanobacteria and their blooms. Cyanobacteria are microorganisms of morphological features of bacteria and algae. They live in colonies, which in large quantities show up as streaks, dense foam on the water surface. The aim of this paper was to assess the impact of cyanobacteria blooms on health regarding bathing water quality in Poland. Materials and methods: Assessment covered all bathing sites in Poland supervised by Polish National Sanitary Inspection (PIS in the period from 2007 to 2009. The base was data collected during bathing water monitoring conducted by PIS and their formal decisions of bathing bans introduced in response to revealed bathing water pollution. Results and discussion: The results of assessment indicate, that about one-fourth of all bathing bans in Poland was due to cyanobacteria blooms. Conclusions: Every fifth bathing sites located on artificial lake or water reservoir and every tenth on the sea bathing sites were polluted. Average period of bathing ban due to cyanobacteria blooms in Poland varies. Relatively the shortest bathing bans were observed on the sea bathing sites (no longer than one week on average. Much longer were bathing bans on lakes and artificial lakes (one month on average.

  2. Origin of marine planktonic cyanobacteria.

    Science.gov (United States)

    Sánchez-Baracaldo, Patricia

    2015-12-01

    Marine planktonic cyanobacteria contributed to the widespread oxygenation of the oceans towards the end of the Pre-Cambrian and their evolutionary origin represents a key transition in the geochemical evolution of the Earth surface. Little is known, however, about the evolutionary events that led to the appearance of marine planktonic cyanobacteria. I present here phylogenomic (135 proteins and two ribosomal RNAs), Bayesian relaxed molecular clock (18 proteins, SSU and LSU) and Bayesian stochastic character mapping analyses from 131 cyanobacteria genomes with the aim to unravel key evolutionary steps involved in the origin of marine planktonic cyanobacteria. While filamentous cell types evolved early on at around 2,600-2,300 Mya and likely dominated microbial mats in benthic environments for most of the Proterozoic (2,500-542 Mya), marine planktonic cyanobacteria evolved towards the end of the Proterozoic and early Phanerozoic. Crown groups of modern terrestrial and/or benthic coastal cyanobacteria appeared during the late Paleoproterozoic to early Mesoproterozoic. Decrease in cell diameter and loss of filamentous forms contributed to the evolution of unicellular planktonic lineages during the middle of the Mesoproterozoic (1,600-1,000 Mya) in freshwater environments. This study shows that marine planktonic cyanobacteria evolved from benthic marine and some diverged from freshwater ancestors during the Neoproterozoic (1,000-542 Mya).

  3. Oleic acid biosynthesis in cyanobacteria

    International Nuclear Information System (INIS)

    VanDusen, W.J.; Jaworski, J.G.

    1986-01-01

    The biosynthesis of fatty acids in cyanobacteria is very similar to the well characterized system found in green plants. However, the initial desaturation of stearic acid in cyanobacteria appears to represent a significant departure from plant systems in which stearoyl-ACP is the exclusive substrate for desaturation. In Anabaena variabilis, the substrate appears to be monoglucosyldiacylglycerol, a lipid not found in plants. The authors examined five different cyanobacteria to determine if the pathway in A. variabilis was generally present in other cyanobacteria. The cyanobacteria studied were A. variabilis, Chlorogloeopsis sp., Schizothrix calcicola, Anacystis marina, and Anacystis nidulans. Each were grown in liquid culture, harvested, and examined for stearoyl-ACP desaturase activity or incubated with 14 CO 2 . None of the cyanobacteria contained any stearoyl-ACP desaturase activity in whole homogenates or 105,000g supernatants. All were capable of incorporating 14 CO 2 into monoglucosyldiacylglycerol and results from incubations of 20 min, 1 hr, 1 hr + 10 hr chase were consistent with monoglucosyldiacylglycerol serving as precursor for monogalctosyldiacylglycerol. Thus, initial evidence is consistent with oleic acid biosynthesis occurring by desaturation of stearoyl-monoglucosyldiacylglycerol in all cyanobacteria

  4. 75 FR 58391 - Proposed Data Collections Submitted for Public Comment and Recommendations

    Science.gov (United States)

    2010-09-24

    ... technology. Written comments should be received within 60 days of this notice. Proposed Project Human... Brief Description Cyanobacteria (also called blue-green algae) can be found in terrestrial, fresh... animals (including other mammals, fish, and birds). A number of human health effects, including...

  5. Newly isolated Nodularia phage influences cyanobacterial community dynamics

    Czech Academy of Sciences Publication Activity Database

    Coloma, S.E.; Dienstbier, Ana; Bamford, D.H.; Sivonen, K.; Roine, E.; Hiltunen, T.

    2017-01-01

    Roč. 19, č. 1 (2017), s. 273-286 ISSN 1462-2912 Institutional support: RVO:61388971 Keywords : Baltic sea cyanobacteria * Blue-green-algae * Nitrogen-fixation Subject RIV: EE - Microbiology , Virology OBOR OECD: Microbiology Impact factor: 5.395, year: 2016

  6. Pringsheim's living legacy: CCALA, CCAP, SAG and UTEX culture collections of algae

    Czech Academy of Sciences Publication Activity Database

    Day, J. G.; Lukavský, Jaromír; Friedl, T.; Brand, J. J.; Campbell, CH. N.; Lorenz, M.; Elster, Josef

    2004-01-01

    Roč. 79, 1-2 (2004), s. 27-37 ISSN 0029-5035 R&D Projects: GA AV ČR KSK6005114 Keywords : cyanobacteria * algae * Pringsheim * algal collections Subject RIV: EF - Botanics Impact factor: 0.594, year: 2004

  7. Next generation paradigm for urban pluvial flood modelling, prediction, management and vulnerability reduction - Interaction between RainGain and Blue Green Dream projects

    Science.gov (United States)

    Maksimovic, C.

    2012-04-01

    The effects of climate change and increasing urbanisation call for a new paradigm for efficient planning, management and retrofitting of urban developments to increase resilience to climate change and to maximize ecosystem services. Improved management of urban floods from all sources in required. Time scale for well documented fluvial and coastal floods allows for timely response but surface (pluvial) flooding caused by intense local storms had not been given appropriate attention, Pitt Review (UK). Urban surface floods predictions require fine scale data and model resolutions. They have to be tackled locally by combining central inputs (meteorological services) with the efforts of the local entities. Although significant breakthrough in modelling of pluvial flooding was made there is a need to further enhance short term prediction of both rainfall and surface flooding. These issues are dealt with in the EU Iterreg project Rain Gain (RG). Breakthrough in urban flood mitigation can only be achieved by combined effects of advanced planning design, construction and management of urban water (blue) assets in interaction with urban vegetated areas' (green) assets. Changes in design and operation of blue and green assets, currently operating as two separate systems, is urgently required. Gaps in knowledge and technology will be introduced by EIT's Climate-KIC Blue Green Dream (BGD) project. The RG and BGD projects provide synergy of the "decoupled" blue and green systems to enhance multiple benefits to: urban amenity, flood management, heat island, biodiversity, resilience to drought thus energy requirements, thus increased quality of urban life at lower costs. Urban pluvial flood management will address two priority areas: Short Term rainfall Forecast and Short term flood surface forecast. Spatial resolution of short term rainfall forecast below 0.5 km2 and lead time of a few hours are needed. Improvements are achievable by combining data sources of raingauge networks

  8. Hydrogen production by Cyanobacteria

    Directory of Open Access Journals (Sweden)

    Chaudhuri Surabhi

    2005-12-01

    Full Text Available Abstract The limited fossil fuel prompts the prospecting of various unconventional energy sources to take over the traditional fossil fuel energy source. In this respect the use of hydrogen gas is an attractive alternate source. Attributed by its numerous advantages including those of environmentally clean, efficiency and renew ability, hydrogen gas is considered to be one of the most desired alternate. Cyanobacteria are highly promising microorganism for hydrogen production. In comparison to the traditional ways of hydrogen production (chemical, photoelectrical, Cyanobacterial hydrogen production is commercially viable. This review highlights the basic biology of cynobacterial hydrogen production, strains involved, large-scale hydrogen production and its future prospects. While integrating the existing knowledge and technology, much future improvement and progress is to be done before hydrogen is accepted as a commercial primary energy source.

  9. Effect of Different Light Qualities on Growth, Pigment Content, Chlorophyll Fluorescence, and Antioxidant Enzyme Activity in the Red Alga Pyropia haitanensis (Bangiales, Rhodophyta).

    Science.gov (United States)

    Wu, Huanyang

    2016-01-01

    Spectral light changes evoke different morphogenetic and photosynthetic responses that can vary among different algae species. The aim of this study is to investigate the photosynthetic characteristics of the red macroalgae grown under different spectrum environments. In this study, Pyropia haitanensis were cultured under blue, red, and green LED and fluorescent tubes light. The growth rate, photopigment composition, chlorophyll fluorescence, and antioxidative enzymes activities in different light spectrums were investigated. The results revealed that growth rate was significantly higher in the thalli grown under blue, green, and fluorescent tubes light. Contents of Chl a and phycobiliprotein in red light were lower among all the growth conditions. Furthermore, a striking increase in SOD and CAT activity was observed in red light treatment along with the NPQ increase. The results revealed that the photosynthetic efficiency and increased growth rate of P. haitanensis benefitted from light spectrums such as blue, green, and fluorescent tubes light by pigment composition and photochemical efficiency manipulation, whereas red light has disadvantageous effects. Accordingly, the results for improving quality and the economic yield of algae species in some extent and the combination of different wavelengths could allow better economic resource exploitation.

  10. Effect of Different Light Qualities on Growth, Pigment Content, Chlorophyll Fluorescence, and Antioxidant Enzyme Activity in the Red Alga Pyropia haitanensis (Bangiales, Rhodophyta

    Directory of Open Access Journals (Sweden)

    Huanyang Wu

    2016-01-01

    Full Text Available Spectral light changes evoke different morphogenetic and photosynthetic responses that can vary among different algae species. The aim of this study is to investigate the photosynthetic characteristics of the red macroalgae grown under different spectrum environments. In this study, Pyropia haitanensis were cultured under blue, red, and green LED and fluorescent tubes light. The growth rate, photopigment composition, chlorophyll fluorescence, and antioxidative enzymes activities in different light spectrums were investigated. The results revealed that growth rate was significantly higher in the thalli grown under blue, green, and fluorescent tubes light. Contents of Chl a and phycobiliprotein in red light were lower among all the growth conditions. Furthermore, a striking increase in SOD and CAT activity was observed in red light treatment along with the NPQ increase. The results revealed that the photosynthetic efficiency and increased growth rate of P. haitanensis benefitted from light spectrums such as blue, green, and fluorescent tubes light by pigment composition and photochemical efficiency manipulation, whereas red light has disadvantageous effects. Accordingly, the results for improving quality and the economic yield of algae species in some extent and the combination of different wavelengths could allow better economic resource exploitation.

  11. Monitoring Cyanobacteria with Satellites Webinar

    Science.gov (United States)

    real-world satellite applications can quantify cyanobacterial harmful algal blooms and related water quality parameters. Provisional satellite derived cyanobacteria data and different software tools are available to state environmental and health agencies.

  12. Freshwater algae competition and correlation between their growth and microcystin production.

    Science.gov (United States)

    Álvarez, Xana; Valero, Enrique; Cancela, Ángeles; Sánchez, Ángel

    2016-11-01

    There are some different freshwater algae in Eutrophic reservoirs which bloom with specific environmental conditions, and some of them are cyanobacteria. In this investigation, we have cultivated microalgae present in natural water samples from a eutrophic reservoir. Variations in temperature and light were evaluated, as well as the competition among different green algae and cyanobacteria. There were three different freshwater algae growing together, Scenedesmus sp., Kirchneriella sp. and Microcystis aeruginosa, this cyanobacterium was the algae that reached the highest development and growth during the culture. While the algae grew, the concentration of toxin (microcystin-LR) increased until it reached the highest levels at 570 μg g -1 . Blooms occurred at temperatures of 28 ± 1.5 °C and light cycles of longer hours of light than dark. This took place during the summer months, from June to September (in the study area). At temperatures below 18 °C, algae did not grow. Blooms were reproduced to a laboratory scale in different conditions in order to understand the development of freshwater algae, as well as to help decision-making about water supply from that reservoir.

  13. 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.

  14. Assembling and maintaining the Photosystem II complex in chloroplasts and cyanobacteria

    Czech Academy of Sciences Publication Activity Database

    Komenda, Josef; Sobotka, Roman; Nixon, P. J.

    2012-01-01

    Roč. 15, č. 3 (2012), s. 245-2051 ISSN 1369-5266 R&D Projects: GA ČR GAP501/10/1000; GA ČR(CZ) GAP501/11/0377; GA MŠk(CZ) ED2.1.00/03.0110; GA AV ČR IAA400200801 Institutional support: RVO:61388971 Keywords : alga * cyanobacteria * Photosystem II Subject RIV: EE - Microbiology, Virology Impact factor: 8.455, year: 2012

  15. Time-resolved spectral studies of blue-green fluorescence of artichoke (Cynara cardunculus L. Var. Scolymus) leaves: identification of chlorogenic acid as one of the major fluorophores and age-mediated changes.

    Science.gov (United States)

    Morales, Fermín; Cartelat, Aurélie; Alvarez-Fernández, Ana; Moya, Ismael; Cerovic, Zoran G

    2005-12-14

    Synchrotron radiation and the time-correlated single-photon counting technique were used to investigate the spectral and time-resolved characteristics of blue-green fluorescence (BGF) of artichoke leaves. Leaves emitted BGF under ultraviolet (UV) excitation; the abaxial side was much more fluorescent than the adaxial side, and in both cases, the youngest leaves were much more fluorescent than the oldest ones. The BGF of artichoke leaves was dominated by the presence of hydroxycinnamic acids. A decrease in the percentage of BGF attributable to the very short kinetic component (from 42 to 20%), in the shape of the BGF excitation spectra, and chlorogenic acid concentrations indicate that there is a loss of hydroxycinnamic acid with leaf age. Studies on excitation, emission, and synchronized fluorescence spectra of leaves and trichomes and chlorogenic acid contents indicate that chlorogenic acid is one of the main blue-green fluorophores in artichoke leaves. Results of the present study indicate that 20-42% (i.e., the very short kinetic component) of the overall BGF is emitted by chlorogenic acid. Time-resolved BGF measurements could be a means to extract information on chlorogenic acid fluorescence from the overall leaf BGF.

  16. Circadian Rhythms in Cyanobacteria

    Science.gov (United States)

    Golden, Susan S.

    2015-01-01

    SUMMARY Life on earth is subject to daily and predictable fluctuations in light intensity, temperature, and humidity created by rotation of the earth. Circadian rhythms, generated by a circadian clock, control temporal programs of cellular physiology to facilitate adaptation to daily environmental changes. Circadian rhythms are nearly ubiquitous and are found in both prokaryotic and eukaryotic organisms. Here we introduce the molecular mechanism of the circadian clock in the model cyanobacterium Synechococcus elongatus PCC 7942. We review the current understanding of the cyanobacterial clock, emphasizing recent work that has generated a more comprehensive understanding of how the circadian oscillator becomes synchronized with the external environment and how information from the oscillator is transmitted to generate rhythms of biological activity. These results have changed how we think about the clock, shifting away from a linear model to one in which the clock is viewed as an interactive network of multifunctional components that are integrated into the context of the cell in order to pace and reset the oscillator. We conclude with a discussion of how this basic timekeeping mechanism differs in other cyanobacterial species and how information gleaned from work in cyanobacteria can be translated to understanding rhythmic phenomena in other prokaryotic systems. PMID:26335718

  17. Evaluation of Military Field-Water Quality. Volume 4. Health Criteria and Recommendations for Standards. Part 1. Chemicals and Properties of Military Concern Associated with Natural and Anthropogenic Sources

    Science.gov (United States)

    1988-02-01

    up to 7 d and 1 y. GENERAL PROPERTIES OF CYANOBACTERIA AND ACTINOMYCETES All algae and bacteria are members of the kingdom Protista. Protists are...distinguished from plants and animals primarily by their simple cellular organization. The algal protists are divided into two categories: (1) blue-green...dinoflagellates. Cyanobacteria, as well as typical bacteria like actinomycetes, are considered lower protists because they are prokaryotic cells (i.e., a

  18. 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

  19. Secondary metabolites of cyanobacteria Nostoc sp.

    Science.gov (United States)

    Kobayashi, Akio; Kajiyama, Shin-Ichiro

    1998-03-01

    Cyanobacteria attracted much attention recently because of their secondary metabolites with potent biological activities and unusual structures. This paper reviews some recent studies on the isolation, structural, elucidation and biological activities of the bioactive compounds from cyanobacteria Nostoc species.

  20. 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.

  1. Grazing livestock are exposed to terrestrial cyanobacteria

    OpenAIRE

    McGorum , Bruce C; Pirie , R Scott; Glendinning , Laura; McLachlan , Gerry; Metcalf , James S; Banack , Sandra A; Cox , Paul A; Codd , Geoffrey A

    2015-01-01

    While toxins from aquatic cyanobacteria are a well-recognised cause of disease in birds and animals, exposure of grazing livestock to terrestrial cyanobacteria has not been described. This study identified terrestrial cyanobacteria, predominantly Phormidium spp., in the biofilm of plants from most livestock fields investigated. Lower numbers of other cyanobacteria, microalgae and fungi were present on many plants. Cyanobacterial 16S rDNA, predominantly from Phormidium spp., was detected in al...

  2. Field and laboratory guide to freshwater cyanobacteria harmful algal blooms for Native American and Alaska Native communities

    Science.gov (United States)

    Rosen, Barry H.; St. Amand, Ann

    2015-09-14

    Cyanobacteria can produce toxins and form harmful algal blooms. The Native American and Alaska Native communities that are dependent on subsistence fishing have an increased risk of exposure to these cyanotoxins. It is important to recognize the presence of an algal bloom in a waterbody and to distinguish a potentially toxic harmful algal bloom from a non-toxic bloom. This guide provides field images that show cyanobacteria blooms, some of which can be toxin producers, as well as other non-toxic algae blooms and floating plants that might be confused with algae. After recognition of a potential toxin-producing cyanobacterial bloom in the field, the type(s) of cyanobacteria present needs to be identified. Species identification, which requires microscopic examination, may help distinguish a toxin-producer from a non-toxin producer. This guide also provides microscopic images of the common cyanobacteria that are known to produce toxins, as well as images of algae that form blooms but do not produce toxins.

  3. Bloom-Forming Cyanobacteria Support Copepod Reproduction and Development in the Baltic Sea

    Science.gov (United States)

    Hogfors, Hedvig; Motwani, Nisha H.; Hajdu, Susanna; El-Shehawy, Rehab; Holmborn, Towe; Vehmaa, Anu; Engström-Öst, Jonna; Brutemark, Andreas; Gorokhova, Elena

    2014-01-01

    It is commonly accepted that summer cyanobacterial blooms cannot be efficiently utilized by grazers due to low nutritional quality and production of toxins; however the evidence for such effects in situ is often contradictory. Using field and experimental observations on Baltic copepods and bloom-forming diazotrophic filamentous cyanobacteria, we show that cyanobacteria may in fact support zooplankton production during summer. To highlight this side of zooplankton-cyanobacteria interactions, we conducted: (1) a field survey investigating linkages between cyanobacteria, reproduction and growth indices in the copepod Acartia tonsa; (2) an experiment testing relationships between ingestion of the cyanobacterium Nodularia spumigena (measured by molecular diet analysis) and organismal responses (oxidative balance, reproduction and development) in the copepod A. bifilosa; and (3) an analysis of long term (1999–2009) data testing relationships between cyanobacteria and growth indices in nauplii of the copepods, Acartia spp. and Eurytemora affinis, in a coastal area of the northern Baltic proper. In the field survey, N. spumigena had positive effects on copepod egg production and egg viability, effectively increasing their viable egg production. By contrast, Aphanizomenon sp. showed a negative relationship with egg viability yet no significant effect on the viable egg production. In the experiment, ingestion of N. spumigena mixed with green algae Brachiomonas submarina had significant positive effects on copepod oxidative balance, egg viability and development of early nauplial stages, whereas egg production was negatively affected. Finally, the long term data analysis identified cyanobacteria as a significant positive predictor for the nauplial growth in Acartia spp. and E. affinis. Taken together, these results suggest that bloom forming diazotrophic cyanobacteria contribute to feeding and reproduction of zooplankton during summer and create a favorable growth

  4. Bloom-forming cyanobacteria support copepod reproduction and development in the Baltic Sea.

    Science.gov (United States)

    Hogfors, Hedvig; Motwani, Nisha H; Hajdu, Susanna; El-Shehawy, Rehab; Holmborn, Towe; Vehmaa, Anu; Engström-Öst, Jonna; Brutemark, Andreas; Gorokhova, Elena

    2014-01-01

    It is commonly accepted that summer cyanobacterial blooms cannot be efficiently utilized by grazers due to low nutritional quality and production of toxins; however the evidence for such effects in situ is often contradictory. Using field and experimental observations on Baltic copepods and bloom-forming diazotrophic filamentous cyanobacteria, we show that cyanobacteria may in fact support zooplankton production during summer. To highlight this side of zooplankton-cyanobacteria interactions, we conducted: (1) a field survey investigating linkages between cyanobacteria, reproduction and growth indices in the copepod Acartia tonsa; (2) an experiment testing relationships between ingestion of the cyanobacterium Nodularia spumigena (measured by molecular diet analysis) and organismal responses (oxidative balance, reproduction and development) in the copepod A. bifilosa; and (3) an analysis of long term (1999-2009) data testing relationships between cyanobacteria and growth indices in nauplii of the copepods, Acartia spp. and Eurytemora affinis, in a coastal area of the northern Baltic proper. In the field survey, N. spumigena had positive effects on copepod egg production and egg viability, effectively increasing their viable egg production. By contrast, Aphanizomenon sp. showed a negative relationship with egg viability yet no significant effect on the viable egg production. In the experiment, ingestion of N. spumigena mixed with green algae Brachiomonas submarina had significant positive effects on copepod oxidative balance, egg viability and development of early nauplial stages, whereas egg production was negatively affected. Finally, the long term data analysis identified cyanobacteria as a significant positive predictor for the nauplial growth in Acartia spp. and E. affinis. Taken together, these results suggest that bloom forming diazotrophic cyanobacteria contribute to feeding and reproduction of zooplankton during summer and create a favorable growth

  5. Harmful Algae Bloom Occurrence in Urban Ponds: Relationship of Toxin Levels with Cell Density and Species Composition

    Science.gov (United States)

    Retention ponds constructed within urban watershed areas of high density populations are common as a result of green infrastructure applications. Several urban ponds in the Northern Kentucky area were monitored for algal community (algae and cyanobacteria) from October 2012 to Se...

  6. Soil algae in brown coal and lignite post-mining areas in central Europe (Czech Republic and Germany)

    Czech Academy of Sciences Publication Activity Database

    Lukešová, Alena

    2001-01-01

    Roč. 9, č. 4 (2001), s. 341-350 ISSN 1061-2971 R&D Projects: GA MŠk ME 076 Institutional research plan: CEZ:AV0Z6066911 Keywords : algae * cyanobacteria * coal mining Subject RIV: EH - Ecology, Behaviour Impact factor: 1.011, year: 2001

  7. Determination and occurrence of retinoids in a eutrophic lake (Taihu Lake, China): cyanobacteria blooms produce teratogenic retinal.

    Science.gov (United States)

    Wu, Xiaoqin; Jiang, Jieqiong; Hu, Jianying

    2013-01-15

    Besides retinoic acids (RAs), some retinoids such as retinal (RAL) and retinol (ROH), which are considered as RA precursors in vertebrates, are also reported to be teratogenic agents. In this study we investigated four RA precursors including RAL, ROH, retinyl palmitate, and β-carotene in the eutrophic Taihu Lake, China, by developing a sensitive analytical method. RAL and β-carotene were widely detected in natural cyanobacteria blooms and lake water. Intracellular concentrations of RAL and β-carotene in blooms were 9.4 to 6.9 × 10(3) and 3.4 to 1.8 × 10(5) ng L(-1), respectively, and their concentrations in lake water were up to 1.4 × 10 ng L(-1) (RAL) and 9.8 × 10(2) ng L(-1) (β-carotene). The good correlation between intracellular concentrations of RAL and RAs implied that RAL was involved in the production of RAs by cyanobacteria blooms. Further examination of 39 cyanobacteria and algae species revealed that most species could produce RAL and β-carotene. The greatest amount of RAL was found in Chlamydomonas sp. (FACHB-715; 1.9 × 10(3) ng g(-1) dry weight). As the main cyanobacteria in Taihu Lake, many Microcystis species could produce high amounts of RAL and were thought to greatly contribute to the production of RAL measured in the blooms. Productions of RAL and β-carotene by cyanobacteria were associated with species, origin location, and growth stage. The results in this study present the existence of a potential risk to aquatic animals living in a eutrophic environment from a high concentration of RAL in cyanobacteria blooms and also provide a clue for further investigating the mechanism underlying the biosynthetic pathway of RAs in cyanobacteria and algae.

  8. IRON-TOLERANT CYANOBACTERIA: IMPLICATIONS FOR ASTROBIOLOGY

    Science.gov (United States)

    Brown, Igor I.; Allen, Carlton C.; Mummey, Daniel L.; Sarkisova, Svetlana A.; McKay, David S.

    2006-01-01

    The review is dedicated to the new group of extremophiles - iron tolerant cyanobacteria. The authors have analyzed earlier published articles about the ecology of iron tolerant cyanobacteria and their diversity. It was concluded that contemporary iron depositing hot springs might be considered as relative analogs of Precambrian environment. The authors have concluded that the diversity of iron-tolerant cyanobacteria is understudied. The authors also analyzed published data about the physiological peculiarities of iron tolerant cyanobacteria. They made the conclusion that iron tolerant cyanobacteria may oxidize reduced iron through the photosystem of cyanobacteria. The involvement of both Reaction Centers 1 and 2 is also discussed. The conclusion that iron tolerant protocyanobacteria could be involved in banded iron formations generation is also proposed. The possible mechanism of the transition from an oxygenic photosynthesis to an oxygenic one is also discussed. In the final part of the review the authors consider the possible implications of iron tolerant cyanobacteria for astrobiology.

  9. 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.)

  10. Temperature optimum of algae living in the outfall of a power plant on Lake Monona

    International Nuclear Information System (INIS)

    Brock, T.D.; Hoffmann, J.

    1974-01-01

    Temperature optima for photosynthesis were measured for algal populations living in the outfall of a fossil-fuel electric power plant on Lake Monona and were compared with the temperature optima of algae living in a control area in the nearby Yahara River. The temperature of the power plant outfall averaged about 8 0 C higher than that of the Yahara River. In the winter, no differences in species composition between the two study areas could be detected, Cladophora and Ulothrix being the dominant algae. The temperature optima of the populations from the two locations were the same, around 27 0 C, although the habitat temperatures at both locations were considerably lower. The only difference in response to temperature seen between the two populations was that the population at the outfall was able to photosynthesize at higher temperature, still showing high photosynthesis at 35 0 C and detectable photosynthesis at 46 0 C, a temperature at which the population from the Yahara River showed no detectable photosynthesis. In the summer, the dominant algae at the power plant outfall were Stigeoclonium and filamentous blue-green algae (family Oscillatoriaceae), whereas at the Yahara River the algal population was almost exclusively Cladophora. The temperature optima of both summer populations were the same, 31.5 0 C, only slightly higher than the mid-winter optima. Again, the population from the power plant was able to photosynthesize at higher temperature than the control population, showing quite active photosynthesis at 42.5 0 C, a temperature at which the population from the Yahara River was completely inactive. (U.S.)

  11. Floating cultivation of marine cyanobacteria using coal fly ash.

    Science.gov (United States)

    Matsumoto, M; Yoshida, E; Takeyama, H; Matsunaga, T

    2000-01-01

    The aim of this study was to develop improved methodologies for bulk culturing of biotechnologically useful marine cyanobacteria in the open ocean. We have investigated the viability of using coal fly ash (CFA) blocks as the support medium in a novel floating culture system for marine micro-algae. The marine cyanobacterium Synechococcus sp. NKBG 040607 was found to adhere to floating CFA blocks in liquid culture medium. Maximum density of attached cells of 2.0 x 10(8) cells/cm2 was achieved using seawater. The marine cyanobacterium Synechococcus sp. NKBG 042902 weakly adhered to floating CFA blocks in BG-11 medium. Increasing the concentration of calcium ion in the culture medium enhanced adherence to CFA blocks.

  12. Catalog of microscopic organisms of the Everglades, Part 1—The cyanobacteria

    Science.gov (United States)

    Rosen, Barry H.; Mareš, Jan

    2016-07-27

    The microscopic organisms of the Everglades include numerous prokaryotic organisms, including the eubacteria, such as the cyanobacteria and non-photosynthetic bacteria, as well as several eukaryotic algae and protozoa that form the base of the food web. This report is part 1 in a series of reports that describe microscopic organisms encountered during the examination of several hundred samples collected in the southern Everglades. Part 1 describes the cyanobacteria and includes a suite of images and the most current taxonomic treatment of each taxon. The majority of the images are of live organisms, allowing their true color to be represented. A number of potential new species are illustrated; however, corroborating evidence from a genetic analysis of the morphological characteristics is needed to confirm these designations as new species. Part 1 also includes images of eubacteria that resemble cyanobacteria. Additional parts of the report on microscopic organisms of the Everglades are currently underway, such as the green algae and diatoms. The report also serves as the basis for a taxonomic image database that will provide a digital record of the Everglades microscopic flora and fauna. It is anticipated that these images will facilitate current and future ecological studies on the Everglades, such as understanding food-web dynamics, sediment formation and accumulation, the effects of nutrients and flow, and climate change.

  13. Algal Diet of Small-Bodied Crustacean Zooplankton in a Cyanobacteria-Dominated Eutrophic Lake.

    Directory of Open Access Journals (Sweden)

    Ilmar Tõnno

    Full Text Available Small-bodied cladocerans and cyclopoid copepods are becoming increasingly dominant over large crustacean zooplankton in eutrophic waters where they often coexist with cyanobacterial blooms. However, relatively little is known about their algal diet preferences. We studied grazing selectivity of small crustaceans (the cyclopoid copepods Mesocyclops leuckarti, Thermocyclops oithonoides, Cyclops kolensis, and the cladocerans Daphnia cucullata, Chydorus sphaericus, Bosmina spp. by liquid chromatographic analyses of phytoplankton marker pigments in the shallow, highly eutrophic Lake Võrtsjärv (Estonia during a seasonal cycle. Copepods (mainly C. kolensis preferably consumed cryptophytes (identified by the marker pigment alloxanthin in gut contents during colder periods, while they preferred small non-filamentous diatoms and green algae (identified mainly by diatoxanthin and lutein, respectively from May to September. All studied cladoceran species showed highest selectivity towards colonial cyanobacteria (identified by canthaxanthin. For small C. sphaericus, commonly occuring in the pelagic zone of eutrophic lakes, colonial cyanobacteria can be their major food source, supporting their coexistence with cyanobacterial blooms. Pigments characteristic of filamentous cyanobacteria and diatoms (zeaxanthin and fucoxanthin, respectively, algae dominating in Võrtsjärv, were also found in the grazers' diet but were generally avoided by the crustaceans commonly dominating the zooplankton assemblage. Together these results suggest that the co-occurring small-bodied cyclopoid and cladoceran species have markedly different algal diets and that the cladocera represent the main trophic link transferring cyanobacterial carbon to the food web in a highly eutrophic lake.

  14. Iron, Sulfur, Arsenic and Water: Geochemical Implications of Facultative Anoxygenic Photosynthesis in Cyanobacteria and the Slow Rise of Oxygen

    Science.gov (United States)

    Wolfe-Simon, F.; Johnston, D. T.; Girguis, P. R.; Pearson, A.; Knoll, A. H.

    2008-12-01

    Over geologic time, the global rise in atmospheric oxygen (O2) is attributed to the evolution and wide spread proliferation of oxygenic photosynthesis in cyanobacteria. However, cyanobacteria maintain a metabolic flexibility that may not always result in O2 release. Specifically, cyanobacteria can use a variety of alternative electron donors, rather than water, that are also readily oxidized. These may include sulfur, iron, and arsenic. Cyanobacteria are thus not uniquely constrained towards O2 production. Changes in the bioavailability of these key elements may have had dramatic consequences for and resulted in the slow accumulation of O2 in the atmosphere. In particular, by using facultative anoxygenic photosynthesis the cells maintain advantageous anaerobic conditions for N2-fixation. Although other types of bacteria are capable of N2-fixation, cyanobacteria singularly possess the dynamic capability of generating and surviving O2. These two processes "pull" the cells in opposite directions, metabolically speaking, around an aerobic-anaerobic continuum. Such a strategy also confers a distinct competitive advantage for cyanobacteria over photosynthetic eukaryotes, as they can endure widespread euxinia and maintain their cellular N quota. In an anoxic and/or sulfidic ocean, cyanobacteria would be expected to dominate over eukaryotic algae. Here we present Bayesian constructed phylogenetic distribution of specific genes and the metabolic role of key enzymes that form the basis of this hypothesis. We further suggest that the consequences of this proposed ecosystem structure altered the redox balance of the fluid Earth (atmosphere and oceans) and can help explain the observed long-term geochemical stasis and slow rates of eukaryotic diversification. We suggest that the underlying control for global oxygenation was a synergistic interplay between the evolution and elastic physiology of cyanobacteria as they impacted the redox state of early Earth.

  15. An Amoebal Grazer of Cyanobacteria Requires Cobalamin Produced by Heterotrophic Bacteria.

    Science.gov (United States)

    Ma, Amy T; Beld, Joris; Brahamsha, Bianca

    2017-05-15

    Amoebae are unicellular eukaryotes that consume microbial prey through phagocytosis, playing a role in shaping microbial food webs. Many amoebal species can be cultivated axenically in rich media or monoxenically with a single bacterial prey species. Here, we characterize heterolobosean amoeba LPG3, a recent natural isolate, which is unable to grow on unicellular cyanobacteria, its primary food source, in the absence of a heterotrophic bacterium, a Pseudomonas species coisolate. To investigate the molecular basis of this requirement for heterotrophic bacteria, we performed a screen using the defined nonredundant transposon library of Vibrio cholerae , which implicated genes in corrinoid uptake and biosynthesis. Furthermore, cobalamin synthase deletion mutations in V. cholerae and the Pseudomonas species coisolate do not support the growth of amoeba LPG3 on cyanobacteria. While cyanobacteria are robust producers of a corrinoid variant called pseudocobalamin, this variant does not support the growth of amoeba LPG3. Instead, we show that it requires cobalamin that is produced by the Pseudomonas species coisolate. The diversity of eukaryotes utilizing corrinoids is poorly understood, and this amoebal corrinoid auxotroph serves as a model for examining predator-prey interactions and micronutrient transfer in bacterivores underpinning microbial food webs. IMPORTANCE Cyanobacteria are important primary producers in aquatic environments, where they are grazed upon by a variety of phagotrophic protists and, hence, have an impact on nutrient flux at the base of microbial food webs. Here, we characterize amoebal isolate LPG3, which consumes cyanobacteria as its primary food source but also requires heterotrophic bacteria as a source of corrinoid vitamins. Amoeba LPG3 specifically requires the corrinoid variant produced by heterotrophic bacteria and cannot grow on cyanobacteria alone, as they produce a different corrinoid variant. This same corrinoid specificity is also

  16. Utilization of the terrestrial cyanobacteria

    Science.gov (United States)

    Katoh, Hiroshi; Tomita-Yokotani, Kaori; Furukawa, Jun; Kimura, Shunta; Yokoshima, Mika; Yamaguchi, Yuji; Takenaka, Hiroyuki

    The terrestrial, N _{2}-fixing cyanobacterium, Nostoc commune has expected to utilize for agriculture, food and terraforming cause of its extracellular polysaccharide, desiccation tolerance and nitrogen fixation. Previously, the first author indicated that desiccation related genes were analyzed and the suggested that the genes were related to nitrogen fixation and metabolisms. In this report, we suggest possibility of agriculture, using the cyanobacterium. Further, we also found radioactive compounds accumulated N. commune (cyanobacterium) in Fukushima, Japan after nuclear accident. Thus, it is investigated to decontaminate radioactive compounds from the surface soil by the cyanobacterium and showed to accumulate radioactive compounds using the cyanobacterium. We will discuss utilization of terrestrial cyanobacteria under closed environment. Keyword: Desiccation, terrestrial cyanobacteria, bioremediation, agriculture

  17. Sucrose in Cyanobacteria: From a Salt-Response Molecule to Play a Key Role in Nitrogen Fixation

    Directory of Open Access Journals (Sweden)

    María A. Kolman

    2015-01-01

    Full Text Available In the biosphere, sucrose is mainly synthesized in oxygenic photosynthetic organisms, such as cyanobacteria, green algae and land plants, as part of the carbon dioxide assimilation pathway. Even though its central position in the functional biology of plants is well documented, much less is known about the role of sucrose in cyanobacteria. In those prokaryotes, sucrose accumulation has been associated with salt acclimation, and considered as a compatible solute in low-salt tolerant strains. In the last years, functional characterizations of sucrose metabolizing enzymes, metabolic control analysis, cellular localization of gene expressions, and reverse genetic experiments have revealed that sucrose metabolism is crucial in the diazotrophic growth of heterocystic strains, and besides, that it can be connected to glycogen synthesis. This article briefly summarizes the current state of knowledge of sucrose physiological functions in modern cyanobacteria and how they might have evolved taking into account the phylogenetic analyses of sucrose enzymes.

  18. Seaweed Bioactive Compounds against Pathogens and Microalgae: Potential Uses on Pharmacology and Harmful Algae Bloom Control.

    Science.gov (United States)

    Zerrifi, Soukaina El Amrani; El Khalloufi, Fatima; Oudra, Brahim; Vasconcelos, Vitor

    2018-02-09

    Cyanobacteria are found globally due to their adaptation to various environments. The occurrence of cyanobacterial blooms is not a new phenomenon. The bloom-forming and toxin-producing species have been a persistent nuisance all over the world over the last decades. Evidence suggests that this trend might be attributed to a complex interplay of direct and indirect anthropogenic influences. To control cyanobacterial blooms, various strategies, including physical, chemical, and biological methods have been proposed. Nevertheless, the use of those strategies is usually not effective. The isolation of natural compounds from many aquatic and terrestrial plants and seaweeds has become an alternative approach for controlling harmful algae in aquatic systems. Seaweeds have received attention from scientists because of their bioactive compounds with antibacterial, antifungal, anti-microalgae, and antioxidant properties. The undesirable effects of cyanobacteria proliferations and potential control methods are here reviewed, focusing on the use of potent bioactive compounds, isolated from seaweeds, against microalgae and cyanobacteria growth.

  19. Spatial analysis of freshwater lake cyanobacteria blooms, 2008-2011

    Science.gov (United States)

    Background/Question/Methods Cyanobacteria and associated harmful algal blooms cause significant social, economic, and environmental impacts. Cyanobacteria synthesize hepatotoxins, neurotoxins, and dermatotoxins, affecting the health of humans and other species. The Cyanobacteria ...

  20. Temperature-dependent effect of filamentous cyanobacteria on Daphnia magna life history traits

    Directory of Open Access Journals (Sweden)

    Piotr DAWIDOWICZ

    2011-08-01

    Full Text Available Filamentous cyanobacteria are unsuitable food for Daphnia due to their poor manageability, poor nutritional value and, in some cases, toxicity. As the strength of harmful effects of cyanobacteria on filter-feeding zooplankton is temperature dependent, the global warming scenarios for eutrophic lakes in temperate zone might include an escalated suppression of Daphnia populations caused by the presence of cyanobacterial filaments. To test this assumption, we conducted life-table experiments with four clones of Daphnia magna fed either a green alga Scenedesmus obliquus or a non-toxic strain of filamentous cyanobacteria Cylindrospermopsis raciborskii in two temperatures (20 °C and 24 °C. Key life history parameters of Daphnia, i.e., age and size at first reproduction, fecundity, and individual growth rate, were measured. Both food and temperature significantly affected Daphnia performance, however, the effect of interaction of these two factors was ambiguous and highly genotype-dependent. We conclude that the temperature increase within the studied range will not necessarily strengthen the suppression of Daphnia growth by filamentous cyanobacteria, but may affect clonal selection within population of Daphnia, thus possibly triggering microevolutionary changes within affected populations.

  1. Primary endosymbiosis: have cyanobacteria and Chlamydiae ever been roommates?

    Directory of Open Access Journals (Sweden)

    Philippe Deschamps

    2014-12-01

    Full Text Available Eukaryotes acquired the ability to process photosynthesis by engulfing a cyanobacterium and transforming it into a genuine organelle called the plastid. This event, named primary endosymbiosis, occurred once more than a billion years ago, and allowed the emergence of the Archaeplastida, a monophyletic supergroup comprising the green algae and plants, the red algae and the glaucophytes. Of the other known cases of symbiosis between cyanobacteria and eukaryotes, none has achieved a comparable level of cell integration nor reached the same evolutionary and ecological success than primary endosymbiosis did. Reasons for this unique accomplishment are still unknown and difficult to comprehend. The exploration of plant genomes has revealed a considerable amount of genes closely related to homologs of Chlamydiae bacteria, and probably acquired by horizontal gene transfer. Several studies have proposed that these transferred genes, which are mostly involved in the functioning of the plastid, may have helped the settlement of primary endosymbiosis. Some of these studies propose that Chlamydiae and cyanobacterial symbionts coexisted in the eukaryotic host of the primary endosymbiosis, and that Chlamydiae provided solutions for the metabolic symbiosis between the cyanobacterium and the host, ensuring the success of primary endosymbiosis. In this review, I present a reevaluation of the contribution of Chlamydiae genes to the genome of Archaeplastida and discuss the strengths and weaknesses of this tripartite model for primary endosymbiosis.

  2. Single and combined effects of microcystin- and saxitoxin-producing cyanobacteria on the fitness and antioxidant defenses of cladocerans.

    Science.gov (United States)

    da S Ferrão-Filho, Aloysio; de Abreu S Silva, Daniel; de Oliveira, Taissa A; de Magalhães, Valéria Freitas; Pflugmacher, Stephan; da Silva, Eduardo Mendes

    2017-10-01

    Cyanobacteria produce different toxic compounds that affect animal life, among them hepatotoxins and neurotoxins. Because cyanobacteria are able to produce a variety of toxic compounds at the same time, organisms may be, generally, subjected to their combined action. In the present study, we demonstrate the single and combined effects on cladocerans of cyanobacteria that produce microcystins (hepatotoxins) and saxitoxins (neurotoxins). Animals were exposed (either singly or combined) to 2 strains of cyanobacteria isolated from the same environment (Funil Reservoir, Rio de Janeiro, Brazil). The effects on clearance rate, mobility, survivorship, fecundity, population increase rate (r), and the antioxidant enzymes glutathione-S-transferase (GST) and catalase (CAT) were measured. Cladoceran species showed a variety of responses to cyanobacterial exposures, going from no effect to impairment of swimming movement, lower survivorship, fecundity, and general fitness (r). Animals ingested cyanobacteria in all treatments, although at lower rates than good food (green algae). Antioxidant defense responses were in accordance with fitness responses, suggesting that oxidative stress may be related to such effects. The present study emphasizes the need for testing combined actions of different classes of toxins, because this is often, and most likely, the scenario in a more eutrophic world with global climatic changes. Environ Toxicol Chem 2017;36:2689-2697. © 2017 SETAC. © 2017 SETAC.

  3. Mineralized remains of morphotypes of filamentous cyanobacteria in carbonaceous meteorites

    Science.gov (United States)

    Hoover, Richard B.

    2005-09-01

    The quest for conclusive evidence of microfossils in meteorites has been elusive. Abiotic microstructures, mineral grains, and even coating artifacts may mimic unicellular bacteria, archaea and nanobacteria with simple spherical or rod morphologies (i.e., cocci, diplococci, bacilli, etc.). This is not the case for the larger and more complex microorganisms, colonies and microbial consortia and ecosystems. Microfossils of algae, cyanobacteria, and cyanobacterial and microbial mats have been recognized and described from many of the most ancient rocks on Earth. The filamentous cyanobacteria and sulphur-bacteria have very distinctive size ranges, complex and recognizable morphologies and visibly differentiated cellular microstructures. The taphonomic modes of fossilization and the life habits and processes of these microorganisms often result in distinctive chemical biosignatures associated with carbonization, silicification, calcification, phosphatization and metal-binding properties of their cell-walls, trichomes, sheaths and extracellular polymeric substances (EPS). Valid biogenicity is provided by the combination of a suite of known biogenic elements (that differ from the meteorite matrix) found in direct association with recognizable and distinct biological features and microstructures (e.g., uniseriate or multiseriate filaments, trichomes, sheaths and cells of proper size/size range); specialized cells (e.g., basal or apical cells, hormogonia, akinetes, and heterocysts); and evidence of growth characteristics (e.g., spiral filaments, robust or thin sheaths, laminated sheaths, true or false branching of trichomes, tapered or uniform filaments) and evidence of locomotion (e.g. emergent cells and trichomes, coiling hormogonia, and hollow or flattened and twisted sheaths). Since 1997 we have conducted Environmental and Field Emission Scanning Electron Microscopy (ESEM and FESEM) studies of freshly fractured interior surfaces of carbonaceous meteorites, terrestrial

  4. 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

  5. Acclimation of green algae to sulfur deficiency: underlying mechanisms and application for hydrogen production.

    Science.gov (United States)

    Antal, Taras K; Krendeleva, Tatyana E; Rubin, Andrew B

    2011-01-01

    Hydrogen is definitely one of the most acceptable fuels in the future. Some photosynthetic microorganisms, such as green algae and cyanobacteria, can produce hydrogen gas from water by using solar energy. In green algae, hydrogen evolution is coupled to the photosynthetic electron transport in thylakoid membranes via reaction catalyzed by the specific enzyme, (FeFe)-hydrogenase. However, this enzyme is highly sensitive to oxygen and can be quickly inhibited when water splitting is active. A problem of incompatibility between the water splitting and hydrogenase reaction can be overcome by depletion of algal cells of sulfur which is essential element for life. In this review the mechanisms underlying sustained hydrogen photoproduction in sulfur deprived C. reinhardtii and the recent achievements in studying of this process are discussed. The attention is focused on the biophysical and physiological aspects of photosynthetic response to sulfur deficiency in green algae.

  6. Cyanobacteria facilitate parasite epidemics in Daphnia.

    Science.gov (United States)

    Tellenbach, C; Tardent, N; Pomati, F; Keller, B; Hairston, N G; Wolinska, J; Spaak, P

    2016-12-01

    The seasonal dominance of cyanobacteria in the phytoplankton community of lake ecosystems can have severe implications for higher trophic levels. For herbivorous zooplankton such as Daphnia, cyanobacteria have poor nutritional value and some species can produce toxins affecting zooplankton survival and reproduction. Here we present another, hitherto largely unexplored aspect of cyanobacteria, namely that they can increase Daphnia susceptibility to parasites. In a 12-yr monthly time-series analysis of the Daphnia community in Greifensee (Switzerland), we observed that cyanobacteria density correlated significantly with the epidemics of a common gut parasite of Daphnia, Caullerya mesnili, regardless of what cyanobacteria species was present or whether it was colonial or filamentous. The temperature from the previous month also affected the occurrence of Caullerya epidemics, either directly or indirectly by the promotion of cyanobacterial growth. A laboratory experiment confirmed that cyanobacteria increase the susceptibility of Daphnia to Caullerya, and suggested a possible involvement of cyanotoxins or other chemical traits of cyanobacteria in this process. These findings expand our understanding of the consequences of toxic cyanobacterial blooms for lake ecosystems and might be relevant for epidemics experienced by other aquatic species. © 2016 by the Ecological Society of America.

  7. Versatility of hydrocarbon production in cyanobacteria.

    Science.gov (United States)

    Xie, Min; Wang, Weihua; Zhang, Weiwen; Chen, Lei; Lu, Xuefeng

    2017-02-01

    Cyanobacteria are photosynthetic microorganisms using solar energy, H 2 O, and CO 2 as the primary inputs. Compared to plants and eukaryotic microalgae, cyanobacteria are easier to be genetically engineered and possess higher growth rate. Extensive genomic information and well-established genetic platform make cyanobacteria good candidates to build efficient biosynthetic pathways for biofuels and chemicals by genetic engineering. Hydrocarbons are a family of compounds consisting entirely of hydrogen and carbon. Structural diversity of the hydrocarbon family is enabled by variation in chain length, degree of saturation, and rearrangements of the carbon skeleton. The diversified hydrocarbons can be used as valuable chemicals in the field of food, fuels, pharmaceuticals, nutrition, and cosmetics. Hydrocarbon biosynthesis is ubiquitous in bacteria, yeasts, fungi, plants, and insects. A wide variety of pathways for the hydrocarbon biosynthesis have been identified in recent years. Cyanobacteria may be superior chassis for hydrocabon production in a photosynthetic manner. A diversity of hydrocarbons including ethylene, alkanes, alkenes, and terpenes can be produced by cyanobacteria. Metabolic engineering and synthetic biology strategies can be employed to improve hydrocarbon production in cyanobacteria. This review mainly summarizes versatility and perspectives of hydrocarbon production in cyanobacteria.

  8. Epilithic algae from caves of the Krakowsko-Częstochowska Upland (Southern Poland

    Directory of Open Access Journals (Sweden)

    Joanna Czerwik-Marcinkowska

    2011-01-01

    Full Text Available This paper describes the first study of algae assemblages in 20 caves in the Krakowsko-Częstochowska Upland (Southern Poland, in the period between 2005-2006. The investigations showed mostly on epilithic algae and their subaeric habitats (rock faces within caves and walls at cave entrances. The morphological and cytological variability of algae were studied in fresh samples, in cultures grown on agar plates and in SPURR preparations. A total of 43 algae species was identified, mostly epilithic species and tolerant of low light intensities. The largest group was formed by representatives of the division Chlorophyta (24 species, and then the division Chrysophyta (Heterokontophyta - 17 species, with 9 species belonging to the class Bacillariophyceae, 7 species - Xanthophyceae and 1 species representing the class Eustigmatophyceae. Dinophyta (2 species constituted the last and the smallest group. Among the collected algae, the following species deserve special attention: Thelesphaera alpina, Bracteacoccus minor, Trachychloron simplex, Tetracystis intermedia and T. cf. isobilateralis. The last species was not earlier found in Europe. Identification of species was greatly aided by examination of cell ultrastructure, which provided an array of further features, increasing chances of correct species identification. Furthermore, the studies focused that algae, although usually remaining under dominance of cyanobacteria, excellently differentiate this special area and even enrich it.

  9. Physical contact and carbon transfer between a lichen-forming Trebouxia alga and a novel Alphaproteobacterium.

    Science.gov (United States)

    Kono, Mieko; Tanabe, Hideyuki; Ohmura, Yoshihito; Satta, Yoko; Terai, Yohey

    2017-05-01

    Recent progress in molecular techniques has begun to alter traditional recognition of lichens as symbiotic organisms comprised of a fungus and photosynthetic partners (green algae and/or cyanobacteria). Diverse organisms, especially various non-photosynthetic bacteria, are now indicated to be integral components of lichen symbiosis. Although lichen-associated bacteria are inferred to have functions that could support the symbiosis, little is known about their physical and nutritional interaction with fungi and algae. In the present study, we identified specific interaction between a lichen-forming alga and a novel bacterium. Trebouxia alga was isolated from a lichen, Usnea hakonensis, and kept as a strain for 8 years. Although no visible bacterial colonies were observed in this culture, high-throughput sequencing of DNA isolated from the culture revealed that the strain is composed of a Trebouxia alga and an Alphaproteobacterium species. In situ hybridization showed that bacterial cells were localized on the surface of the algal cells. Physiological assays revealed that the bacterium was able to use ribitol, glucose and mannitol, all of which are known to exist abundantly in lichens. It was resistant to three antibiotics. Bacteria closely related to this species were also identified in lichen specimens, indicating that U. hakonensis may commonly associate with this group of bacteria. These features of the novel bacterium suggest that it may be involved in carbon cycling of U. hakonensis as a member of lichen symbiosis and less likely to have become associated with the alga after isolation from a lichen.

  10. Identification of aquatically available carbon from algae through solution-state NMR of whole (13)C-labelled cells.

    Science.gov (United States)

    Akhter, Mohammad; Dutta Majumdar, Rudraksha; Fortier-McGill, Blythe; Soong, Ronald; Liaghati-Mobarhan, Yalda; Simpson, Myrna; Arhonditsis, George; Schmidt, Sebastian; Heumann, Hermann; Simpson, André J

    2016-06-01

    Green algae and cyanobacteria are primary producers with profound impact on food web functioning. Both represent key carbon sources and sinks in the aquatic environment, helping modulate the dissolved organic matter balance and representing a potential biofuel source. Underlying the impact of algae and cyanobacteria on an ecosystem level is their molecular composition. Herein, intact (13)C-labelled whole cell suspensions of Chlamydomonas reinhardtii, Chlorella vulgaris and Synechocystis were studied using a variety of 1D and 2D (1)H/(13)C solution-state nuclear magnetic resonance (NMR) spectroscopic experiments. Solution-state NMR spectroscopy of whole cell suspensions is particularly relevant as it identifies species that are mobile (dissolved or dynamic gels), 'aquatically available' and directly contribute to the aquatic carbon pool upon lysis, death or become a readily available food source on consumption. In this study, a wide range of metabolites and structural components were identified within the whole cell suspensions. In addition, significant differences in the lipid/triacylglyceride (TAG) content of green algae and cyanobacteria were confirmed. Mobile species in algae are quite different from those in abundance in 'classic' dissolved organic matter (DOM) indicating that if algae are major contributors to DOM, considerable selective preservation of minor components (e.g. sterols) or biotransformation would have to occur. Identifying the metabolites and dissolved components within algal cells by NMR permits future studies of carbon transfer between species and through the food chain, whilst providing a foundation to better understand the role of algae in the formation of DOM and the sequestration/transformation of carbon in aquatic environments.

  11. Detection of Cyanotoxins in Algae Dietary Supplements.

    Science.gov (United States)

    Roy-Lachapelle, Audrey; Solliec, Morgan; Bouchard, Maryse F; Sauvé, Sébastien

    2017-02-25

    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.

  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. Engineering cyanobacteria as photosynthetic feedstock factories.

    Science.gov (United States)

    Hays, Stephanie G; Ducat, Daniel C

    2015-03-01

    Carbohydrate feedstocks are at the root of bioindustrial production and are needed in greater quantities than ever due to increased prioritization of renewable fuels with reduced carbon footprints. Cyanobacteria possess a number of features that make them well suited as an alternative feedstock crop in comparison to traditional terrestrial plant species. Recent advances in genetic engineering, as well as promising preliminary investigations of cyanobacteria in a number of distinct production regimes have illustrated the potential of these aquatic phototrophs as biosynthetic chassis. Further improvements in strain productivities and design, along with enhanced understanding of photosynthetic metabolism in cyanobacteria may pave the way to translate cyanobacterial theoretical potential into realized application.

  14. Harnessing transcription for bioproduction in cyanobacteria

    DEFF Research Database (Denmark)

    Stensjö, Karin; Vavitsas, Konstantinos; Tyystjärvi, Taina

    2018-01-01

    Sustainable production of biofuels and other valuable compounds is one of our future challenges. One tempting possibility is to use photosynthetic cyanobacteria as production factories. Currently, tools for genetic engineering of cyanobacteria are yet not good enough to exploit the full potential...... of cyanobacteria. A wide variety of expression systems will be required to adjust both the expression of heterologous enzyme(s) and metabolic routes to the best possible balance, allowing the optimal production of a particular substance. In bacteria, transcription, especially the initiation of transcription, has...

  15. Challenges for mapping cyanotoxin patterns from remote sensing of cyanobacteria

    Science.gov (United States)

    Stumpf, Rick P; Davis, Timothy W.; Wynne, Timothy T.; Graham, Jennifer L.; Loftin, Keith A.; Johengen, T.H.; Gossiaux, D.; Palladino, D.; Burtner, A.

    2016-01-01

    Using satellite imagery to quantify the spatial patterns of cyanobacterial toxins has several challenges. These challenges include the need for surrogate pigments – since cyanotoxins cannot be directly detected by remote sensing, the variability in the relationship between the pigments and cyanotoxins – especially microcystins (MC), and the lack of standardization of the various measurement methods. A dual-model strategy can provide an approach to address these challenges. One model uses either chlorophyll-a (Chl-a) or phycocyanin (PC) collected in situ as a surrogate to estimate the MC concentration. The other uses a remote sensing algorithm to estimate the concentration of the surrogate pigment. Where blooms are mixtures of cyanobacteria and eukaryotic algae, PC should be the preferred surrogate to Chl-a. Where cyanobacteria dominate, Chl-a is a better surrogate than PC for remote sensing. Phycocyanin is less sensitive to detection by optical remote sensing, it is less frequently measured, PC laboratory methods are still not standardized, and PC has greater intracellular variability. Either pigment should not be presumed to have a fixed relationship with MC for any water body. The MC-pigment relationship can be valid over weeks, but have considerable intra- and inter-annual variability due to changes in the amount of MC produced relative to cyanobacterial biomass. To detect pigments by satellite, three classes of algorithms (analytic, semi-analytic, and derivative) have been used. Analytical and semi-analytical algorithms are more sensitive but less robust than derivatives because they depend on accurate atmospheric correction; as a result derivatives are more commonly used. Derivatives can estimate Chl-a concentration, and research suggests they can detect and possibly quantify PC. Derivative algorithms, however, need to be standardized in order to evaluate the reproducibility of parameterizations between lakes. A strategy for producing useful estimates

  16. Photomixotrophic chemical production in cyanobacteria.

    Science.gov (United States)

    Matson, Morgan M; Atsumi, Shota

    2018-04-01

    The current global dependence on fossil fuels for both energy and chemical production has spurred concerns regarding long-term resource security and environmental detriments resulting from increased CO 2 levels. Through the installation of exogenous metabolic pathways, engineered cyanobacteria strains can directly fix CO 2 into industrially relevant chemicals currently produced from petroleum. This review highlights some of the studies that have successfully implemented photomixotrophic conditions to increase cyanobacterial chemical production. Supplementation with fixed carbon sources provides additional carbon building blocks and energy to enhance production and occasionally aid in growth. Photomixotrophic production has increased titers up to 5-fold over traditional autotrophic conditions, demonstrating promising applications for future commercialization. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Liberation of ammonia by cyanobacteria

    International Nuclear Information System (INIS)

    Newton, J.W.

    1986-01-01

    Photoheterotrophic nitrogen-fixing cyanobacteria release ammonia when treated with methionine sulfoximine (MSX) to inhibit nitrogen incorporation into protein. This released ammonia can be derived from recently fixed nitrogen (nitrogen atmosphere) or endogenous reserves (argon atmosphere). Anaerobic ammonia release requires light and is stimulated by the photosystem II herbicides DCMU and Atrazine, regardless of the source of ammonia. As much as one quarter of the total cellular nitrogen can be released as ammonia by cyanbacteria treated with MSX and DCMU under argon in light. Chromatography of cell extracts indicates that virtually all cellular proteins are degraded. DCMU and Atrazine, at very low concentration, inhibit sustained uptake of the ammonia analog 14 C methylamine. These data indicate that the herbicides interrupt ammonia uptake and retention by the cells, and support a role for photosystem II in ammonia metabolism

  18. Liberation of ammonia by cyanobacteria

    Energy Technology Data Exchange (ETDEWEB)

    Newton, J.W.

    1986-04-01

    Photoheterotrophic nitrogen-fixing cyanobacteria release ammonia when treated with methionine sulfoximine (MSX) to inhibit nitrogen incorporation into protein. This released ammonia can be derived from recently fixed nitrogen (nitrogen atmosphere) or endogenous reserves (argon atmosphere). Anaerobic ammonia release requires light and is stimulated by the photosystem II herbicides DCMU and Atrazine, regardless of the source of ammonia. As much as one quarter of the total cellular nitrogen can be released as ammonia by cyanbacteria treated with MSX and DCMU under argon in light. Chromatography of cell extracts indicates that virtually all cellular proteins are degraded. DCMU and Atrazine, at very low concentration, inhibit sustained uptake of the ammonia analog /sup 14/C methylamine. These data indicate that the herbicides interrupt ammonia uptake and retention by the cells, and support a role for photosystem II in ammonia metabolism.

  19. Hydrogen production by several cyanobacteria

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Dhruv; Kumar, H.D. (Banaras Hindu Univ., Varanasi (India). Dept. of Botany)

    1992-11-01

    Twenty species belonging to eleven genera of nitrogen-fixing and non-nitrogen-fixing cyanobacteria were screened for production of hydrogen. Only one species each of Nostoc and Anabaena showed light-and nitrogenase-dependent aerobic hydrogen production. The highest rate of aerobic hydrogen production was recorded in Anabaena sp. strain CA. When incubated anaerobically under 99% Ar + 1% CO[sub 2], all the tested strains produced hydrogen. Nickel supplementation completely abolished hydrogen production both under aerobic and anaerobic conditions, except in Anabaena sp. strain CA, where only the rate of production was decreased. Species of Plectonema, Oscillatoria and Spirulina showed methyl viologen-dependent (hydrogenase-dependent) hydrogen production. Other physiological activities were also studied with a view to selecting a suitable organism for large-scale production of hydrogen. (author)

  20. Consequences of Modification of Photosystem Stoichiometry and Amount in Cyanobacteria

    Energy Technology Data Exchange (ETDEWEB)

    Vermaas, Willem [Arizona State Univ., Tempe, AZ (United States)

    2016-12-13

    The proposed research seeks to address two interconnected, important questions that impact photosynthetic processes and that reflect key differences between the photosynthetic systems of cyanobacteria and plants or algae. The first question is what are the reasons and consequences of the high photosystem I / photosystem II (PS I/PS II) ratio in many cyanobacteria, vs. a ratio that is close to unity in many plants and algae. The corresponding hypothesis is that most of PS I functions in cyclic electron transport, and that reduction in PS I will result primarily in a shortage of ATP rather than reducing power. This hypothesis will be tested by reducing the amount of PS I by changing the promoter region of the psaAB operon in the cyanobacterium Synechocystis sp. PCC 6803 and generating a range of mutants with different PS I content and thereby different PS I/PS II ratios, with some of the mutants having a PS II/PS I ratio closer to that in plants. The resulting mutants will be probed in terms of their growth rates, electron transfer rates, and P700 redox kinetics. A second question relates to a Mehler-type reaction catalyzed by two flavoproteins, Flv1 and Flv3, that accept electrons from PS I and that potentially function as an electron safety valve leading to no useful purpose of the photosynthesis-generated electrons. The hypothesis to be tested is that Flv1 and Flv3 use the electrons for useful purposes such as cyclic electron flow around PS I. This hypothesis will be tested by analysis of a mutant strain lacking flv3, the gene for one of the flavoproteins. This research is important for a more detailed understanding of the consequences of photosystem stoichiometry and amounts in a living system. Such an understanding is critical for not only insights in the regulatory systems of the organism but also to guide the development of biological or bio-hybrid systems for solar energy conversion into fuels.

  1. Diel infection of cyanobacteria by cyanophages

    Directory of Open Access Journals (Sweden)

    Tianchi eNi

    2016-01-01

    Full Text Available Cyanobacteria exhibit biological rhythms as an adaptation to the daily light-dark (diel cycle. Light is also crucial for bacteriophages (cyanophages that infect cyanobacteria. As the first step of infection, the adsorption of some cyanophages to their host cells is light-dependent. Moreover, cyanophage replication is affected by light intensity and possibly the host cell cycle. Photosynthesis and carbon metabolism genes have been found in cyanophage genomes. With these genes, cyanophages may affect the host metabolic rhythm. Field studies suggest that cyanophage infection of cyanobacteria in aquatic environments is synchronized directly or indirectly to the light-dark cycle. These discoveries are beginning to reveal how the daily light-dark cycle shapes the interaction of cyanophages and cyanobacteria, which eventually influences matter and energy transformation in aquatic environments.

  2. Engineering cyanobacteria for fuels and chemicals production.

    Science.gov (United States)

    Zhou, Jie; Li, Yin

    2010-03-01

    The world's energy and global warming crises call for sustainable, renewable, carbon-neutral alternatives to replace fossil fuel resources. Currently, most biofuels are produced from agricultural crops and residues, which lead to concerns about food security and land shortage. Compared to the current biofuel production system, cyanobacteria, as autotrophic prokaryotes, do not require arable land and can grow to high densities by efficiently using solar energy, CO(2), water, and inorganic nutrients. Moreover, powerful genetic techniques of cyanobacteria have been developed. For these reasons, cyanobacteria, which carry out oxygenic photosynthesis, are attractive hosts for production of fuels and chemicals. Recently, several chemicals including ethanol, isobutanol and isoprene have been produced by engineered cyanobacteria directly using solar energy, CO(2), and water. Cyanobacterium is therefore a potential novel cell factory for fuels and chemicals production to address global energy security and climate change issues.

  3. Degradation of crude oil by marine cyanobacteria

    Digital Repository Service at National Institute of Oceanography (India)

    Raghukumar, C.; Vipparty, V.; David, J.J.; Chandramohan, D.

    The marine cyanobacteria Oscillatoria salina Biswas, Plectonema terebrans Bornet et Flanhault and Aphanocapsa sp. degraded Bombay High crude oil when grown in artificial seawater nutrients as well as in plain natural seawater. Oil removals...

  4. Human health effects and remotely sensed cyanobacteria

    Science.gov (United States)

    Cyanobacteria blooms (HAB) pose a potential health risk to beachgoers, including HAB-associated gastrointestinal, respiratory and dermal illness. We conducted a prospective study of beachgoers at a Great Lakes beach during July – September, 2003. We recorded each participan...

  5. Measuring N2 Pressure Using Cyanobacteria

    Science.gov (United States)

    Silverman, S. N.; Kopf, S.; Gordon, R.; Bebout, B.; Som, S.

    2017-11-01

    We have shown that cyanobacteria can record information about N2 partial pressure both morphologically and isotopically, and thus may serve as useful geobarometers to help us better understand Earth's ancient atmosphere.

  6. Agencies collaborate, develop a cyanobacteria assessment network

    Science.gov (United States)

    Schaeffer, Blake A.; Loftin, Keith A.; Stumpf, Richard P.; Werdell, P. Jeremy

    2015-01-01

    Cyanobacteria are a genetically diverse group of photosynthetic microorganisms that occupy a broad range of habitats on land and water all over the world. They release toxins that can cause lung and skin irritation, alter the taste and odor of potable water, and cause human and animal illness. Cyanobacteria blooms occur worldwide, and climate change may increase the frequency, duration, and extent of these bloom events.

  7. Co-occurrence of the Cyanotoxins BMAA, DABA and Anatoxin-a in Nebraska Reservoirs, Fish, and Aquatic Plants

    OpenAIRE

    Al-Sammak, Maitham; Hoagland, Kyle; Cassada, David; Snow, Daniel

    2014-01-01

    Several groups of microorganisms are capable of producing toxins in aquatic environments. Cyanobacteria are prevalent blue green algae in freshwater systems, and many species produce cyanotoxins which include a variety of chemical irritants, hepatotoxins and neurotoxins. Production and occurrence of potent neurotoxic cyanotoxins β-N-methylamino-l-alanine (BMAA), 2,4-diaminobutyric acid dihydrochloride (DABA), and anatoxin-a are especially critical with environmental implications to public and...

  8. Using an enzyme linked immunosorbent assay (ELISA) and a protein phosphatase inhibition assay (PPIA) for the detection of microcystins and nodularins.

    Science.gov (United States)

    Carmichael, W W; An, J

    1999-01-01

    Cyanotoxins produced by cyanobacteria (blue-green algae) include potent neurotoxins and hepatotoxins. The hepatotoxins include cyclic peptide microcystins and nodularins plus the alkaloid cylindrospermopsins. Among the cyanotoxins the microcystins have proven to be the most widespread, and are most often implicated in animal and human poisonings. This paper presents a practical guide to two widely used methods for detecting and quantifying microcystins and nodularins in environmental samples-the enzyme linked immunosorbant assay (ELISA) and the protein phosphatase inhibition assay (PPIA).

  9. Cyanobacteria produce a high variety of hepatotoxic peptides in lichen symbiosis

    Science.gov (United States)

    Kaasalainen, Ulla; Fewer, David P.; Jokela, Jouni; Wahlsten, Matti; Sivonen, Kaarina; Rikkinen, Jouko

    2012-01-01

    Lichens are symbiotic associations between fungi and photosynthetic algae or cyanobacteria. Microcystins are potent toxins that are responsible for the poisoning of both humans and animals. These toxins are mainly associated with aquatic cyanobacterial blooms, but here we show that the cyanobacterial symbionts of terrestrial lichens from all over the world commonly produce microcystins. We screened 803 lichen specimens from five different continents for cyanobacterial toxins by amplifying a part of the gene cluster encoding the enzyme complex responsible for microcystin production and detecting toxins directly from lichen thalli. We found either the biosynthetic genes for making microcystins or the toxin itself in 12% of all analyzed lichen specimens. A plethora of different microcystins was found with over 50 chemical variants, and many of the variants detected have only rarely been reported from free-living cyanobacteria. In addition, high amounts of nodularin, up to 60 μg g−1, were detected from some lichen thalli. This microcystin analog and potent hepatotoxin has previously been known only from the aquatic bloom-forming genus Nodularia. Our results demonstrate that the production of cyanobacterial hepatotoxins in lichen symbiosis is a global phenomenon and occurs in many different lichen lineages. The very high genetic diversity of the mcyE gene and the chemical diversity of microcystins suggest that lichen symbioses may have been an important environment for diversification of these cyanobacteria. PMID:22451908

  10. Fluorescence probes for real-time remote cyanobacteria monitoring: A review of challenges and opportunities.

    Science.gov (United States)

    Bertone, Edoardo; Burford, Michele A; Hamilton, David P

    2018-05-10

    In recent years, there has been a widespread deployment of submersible fluorescence sensors by water utilities. They are used to measure diagnostic pigments and estimate algae and cyanobacteria abundance in near real-time. Despite being useful and promising tools, operators and decision-makers often rely on the data provided by these probes without a full understanding of their limitations. As a result, this may lead to wrong and misleading estimations which, in turn, means that researchers and technicians distrust these sensors. In this review paper, we list and discuss the main limitations of such probes, as well as identifying the effect of environmental factors on pigment production, and in turn, the conversion to cyanobacteria abundance estimation. We argue that a comprehensive calibration approach to obtain reliable readings goes well beyond manufacturers' recommendations, and should involve several context-specific experiments. We also believe that if such a comprehensive set of experiments is conducted, the data collected from fluorescence sensors could be used in artificial intelligence modelling approaches to reliably predict, in near real-time, the presence and abundance of different cyanobacteria species. This would have significant benefits for both drinking and recreational water management, given that cyanobacterial toxicity, and taste and odour compounds production, are species-dependent. Copyright © 2018 Elsevier Ltd. All rights reserved.

  11. Horizontal transfer of a eukaryotic plastid-targeted protein gene to cyanobacteria

    Directory of Open Access Journals (Sweden)

    Keeling Patrick J

    2007-06-01

    Full Text Available Abstract Background Horizontal or lateral transfer of genetic material between distantly related prokaryotes has been shown to play a major role in the evolution of bacterial and archaeal genomes, but exchange of genes between prokaryotes and eukaryotes is not as well understood. In particular, gene flow from eukaryotes to prokaryotes is rarely documented with strong support, which is unusual since prokaryotic genomes appear to readily accept foreign genes. Results Here, we show that abundant marine cyanobacteria in the related genera Synechococcus and Prochlorococcus acquired a key Calvin cycle/glycolytic enzyme from a eukaryote. Two non-homologous forms of fructose bisphosphate aldolase (FBA are characteristic of eukaryotes and prokaryotes respectively. However, a eukaryotic gene has been inserted immediately upstream of the ancestral prokaryotic gene in several strains (ecotypes of Synechococcus and Prochlorococcus. In one lineage this new gene has replaced the ancestral gene altogether. The eukaryotic gene is most closely related to the plastid-targeted FBA from red algae. This eukaryotic-type FBA once replaced the plastid/cyanobacterial type in photosynthetic eukaryotes, hinting at a possible functional advantage in Calvin cycle reactions. The strains that now possess this eukaryotic FBA are scattered across the tree of Synechococcus and Prochlorococcus, perhaps because the gene has been transferred multiple times among cyanobacteria, or more likely because it has been selectively retained only in certain lineages. Conclusion A gene for plastid-targeted FBA has been transferred from red algae to cyanobacteria, where it has inserted itself beside its non-homologous, functional analogue. Its current distribution in Prochlorococcus and Synechococcus is punctate, suggesting a complex history since its introduction to this group.

  12. Forecasting cyanobacteria dominance in Canadian temperate lakes.

    Science.gov (United States)

    Persaud, Anurani D; Paterson, Andrew M; Dillon, Peter J; Winter, Jennifer G; Palmer, Michelle; Somers, Keith M

    2015-03-15

    Predictive models based on broad scale, spatial surveys typically identify nutrients and climate as the most important predictors of cyanobacteria abundance; however these models generally have low predictive power because at smaller geographic scales numerous other factors may be equally or more important. At the lake level, for example, the ability to forecast cyanobacteria dominance is of tremendous value to lake managers as they can use such models to communicate exposure risks associated with recreational and drinking water use, and possible exposure to algal toxins, in advance of bloom occurrence. We used detailed algal, limnological and meteorological data from two temperate lakes in south-central Ontario, Canada to determine the factors that are closely linked to cyanobacteria dominance, and to develop easy to use models to forecast cyanobacteria biovolume. For Brandy Lake (BL), the strongest and most parsimonious model for forecasting % cyanobacteria biovolume (% CB) included water column stability, hypolimnetic TP, and % cyanobacteria biovolume two weeks prior. For Three Mile Lake (TML), the best model for forecasting % CB included water column stability, hypolimnetic TP concentration, and 7-d mean wind speed. The models for forecasting % CB in BL and TML are fundamentally different in their lag periods (BL = lag 1 model and TML = lag 2 model) and in some predictor variables despite the close proximity of the study lakes. We speculate that three main factors (nutrient concentrations, water transparency and lake morphometry) may have contributed to differences in the models developed, and may account for variation observed in models derived from large spatial surveys. Our results illustrate that while forecast models can be developed to determine when cyanobacteria will dominate within two temperate lakes, the models require detailed, lake-specific calibration to be effective as risk-management tools. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Biodegradation of phenanthrene by the green alga scenedesmus obliquus ES-55

    Energy Technology Data Exchange (ETDEWEB)

    Safonova, E.; Kvitko, K. [Biological Institute of St. Petersburg State University, Oranienbaum Chaussee 2, Old Peterhof, 198504 St. Petersburg (Russian Federation); Kuschk, P.; Moeder, M. [UFZ-Umweltforschungszentrum Leipzig-Halle GmbH, Permoserstrasse 15, Leipzig (Germany); Reisser, W. [Universitaet Leipzig, Botanisches Institut, Johannisallee 21-23, D-04103 Leipzig (Germany)

    2005-06-01

    While the degradation of polycyclic aromatic hydrocarbons by bacteria and fungi has been broadly investigated, less is known about the metabolism of these compounds by algae. The goal of the experiments was to test the degradability of phenanthrene by the green alga Scenedesmus obliquus ES-55 (Chlorophyceae) and to identify the metabolites. It was shown that S. obliquus ES-55 metabolized phenanthrene. Under light conditions, phenanthrene (14 mg/L) inhibits cell division by more than twice. However, the metabolic processes in the cells affected by phenanthrene continued because the content of chlorophyll increased. In the exponential phase under phototrophic conditions the alga degraded phenanthrene. Phenanthrene was removed by algae up to 42 % in BBM medium and up to 24 % in Kuhl medium. Dihydroxy-dihydro-phenanthrene, a degradation metabolite in fungi, bacteria and cyanobacteria, could also be detected as a transformation product of S. obliquus ES-55. Further detected common metabolites foster the assumption that both phototrophic and non-photothrophic organisms metabolize phenanthrene via a similar pathway. The present study is the first evidence of the ability of an axenic culture of the green alga S. obliquus to biotransform phenanthrene into other metabolites. (Abstract Copyright [2005], Wiley Periodicals, Inc.)

  14. Diversity and community structure of cyanobacteria and other microbes in recycling irrigation reservoirs.

    Science.gov (United States)

    Kong, Ping; Richardson, Patricia; Hong, Chuanxue

    2017-01-01

    Recycling irrigation reservoirs (RIRs) are emerging aquatic environments of global significance to crop production, water conservation and environmental sustainability. This study characterized the diversity and population structure of cyanobacteria and other detected microbes in water samples from eight RIRs and one adjacent runoff-free stream at three ornamental crop nurseries in eastern (VA1 and VA3) and central (VA2) Virginia after cloning and sequencing the 16S rRNA gene targeting cyanobacteria and chloroplast of eukaryotic phytoplankton. VA1 and VA2 utilize a multi-reservoir recycling irrigation system with runoff channeled to a sedimentation reservoir which then overflows into transition and retention reservoirs where water was pumped for irrigation. VA3 has a single sedimentation reservoir which was also used for irrigation. A total of 208 operational taxonomic units (OTU) were identified from clone libraries of the water samples. Among them, 53 OTUs (358 clones) were cyanobacteria comprising at least 12 genera dominated by Synechococcus species; 59 OTUs (387 clones) were eukaryotic phytoplankton including green algae and diatoms; and 96 were other bacteria (111 clones). Overall, cyanobacteria were dominant in sedimentation reservoirs, while eukaryotic phytoplankton and other bacteria were dominant in transition/retention reservoirs and the stream, respectively. These results are direct evidence demonstrating the negative impact of nutrient-rich horticultural runoff, if not contained, on natural water resources. They also help in understanding the dynamics of water quality in RIRs and have practical implications. Although both single- and multi-reservoir recycling irrigation systems reduce the environmental footprint of horticultural production, the former is expected to have more cyanobacterial blooming, and consequently water quality issues, than the latter. Thus, a multi-reservoir recycling irrigation system should be preferred where feasible.

  15. Cyanobacteria and macroalgae in ecosystem of the Neva estuary

    Directory of Open Access Journals (Sweden)

    Nikulina V. N.

    2011-07-01

    Full Text Available The Baltic Sea and Neva estuary are plagued by coastal eutrophication. In order to estimate the scale of the problem, quantitative estimates of phytoplankton and macroalgal mats were determined in the Neva estuary. Long-term monitoring (1982–2009 of phytoplankton showed changes in its species composition and abundance. Summer phytoplankton biomass increased significantly in the 1990s, with concomitant changes in species composition, despite a decline of nutrients in the Neva estuary. The cyanobacteria Planktothrix agardhii became a dominant species. The summer biomass of phytoplankton reached a maximum of 5.2 ± 0.4 mg·L-1 in 2002–2004. Monitoring of macroalgal community in the coastal area of the Neva estuary from 2002 to 2009 showed the dominance of the filamentous green alga Cladophora glomerata in the phytobenthos. Average biomass of macroalgae in inner and outer estuary differed significantly at 132 ± 29 and 310 ± 67 g DW·m-2, respectively. This study showed, that fluctuations in macroalgal biomass reflected human influence on estuary, although it was less sensitive to human impact than the phytoplankton community. Thus qualitative and quantitative characteristics of phytoplankton and macroalgal blooms can indicate anthropogenic influence on the ecosystem, and help to better manage the Neva estuary.

  16. Subcellular pigment distribution is altered under far-red light acclimation in cyanobacteria that contain chlorophyll f.

    Science.gov (United States)

    Majumder, Erica L-W; Wolf, Benjamin M; Liu, Haijun; Berg, R Howard; Timlin, Jerilyn A; Chen, Min; Blankenship, Robert E

    2017-11-01

    Far-Red Light (FRL) acclimation is a process that has been observed in cyanobacteria and algae that can grow solely on light above 700 nm. The acclimation to FRL results in rearrangement and synthesis of new pigments and pigment-protein complexes. In this study, cyanobacteria containing chlorophyll f, Synechococcus sp. PCC 7335 and Halomicronema hongdechloris, were imaged as live cells with confocal microscopy. H. hongdechloris was further studied with hyperspectral confocal fluorescence microscopy (HCFM) and freeze-substituted thin-section transmission electron microscopy (TEM). Under FRL, phycocyanin-containing complexes and chlorophyll-containing complexes were determined to be physically separated and the synthesis of red-form phycobilisome and Chl f was increased. The timing of these responses was observed. The heterogeneity and eco-physiological response of the cells was noted. Additionally, a gliding motility for H. hongdechloris is reported.

  17. The origin of multicellularity in cyanobacteria

    Science.gov (United States)

    2011-01-01

    Background Cyanobacteria are one of the oldest and morphologically most diverse prokaryotic phyla on our planet. The early development of an oxygen-containing atmosphere approximately 2.45 - 2.22 billion years ago is attributed to the photosynthetic activity of cyanobacteria. Furthermore, they are one of the few prokaryotic phyla where multicellularity has evolved. Understanding when and how multicellularity evolved in these ancient organisms would provide fundamental information on the early history of life and further our knowledge of complex life forms. Results We conducted and compared phylogenetic analyses of 16S rDNA sequences from a large sample of taxa representing the morphological and genetic diversity of cyanobacteria. We reconstructed ancestral character states on 10,000 phylogenetic trees. The results suggest that the majority of extant cyanobacteria descend from multicellular ancestors. Reversals to unicellularity occurred at least 5 times. Multicellularity was established again at least once within a single-celled clade. Comparison to the fossil record supports an early origin of multicellularity, possibly as early as the "Great Oxygenation Event" that occurred 2.45 - 2.22 billion years ago. Conclusions The results indicate that a multicellular morphotype evolved early in the cyanobacterial lineage and was regained at least once after a previous loss. Most of the morphological diversity exhibited in cyanobacteria today —including the majority of single-celled species— arose from ancient multicellular lineages. Multicellularity could have conferred a considerable advantage for exploring new niches and hence facilitated the diversification of new lineages. PMID:21320320

  18. Potential of industrial biotechnology with cyanobacteria and eukaryotic microalgae.

    NARCIS (Netherlands)

    Wijffels, R.H.; Kruse, O.; Hellingwerf, K.J.

    2013-01-01

    Both cyanobacteria and eukaryotic microalgae are promising organisms for sustainable production of bulk products such as food, feed, materials, chemicals and fuels. In this review we will summarize the potential and current biotechnological developments. Cyanobacteria are promising host organisms

  19. 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.

  20. Cyanobacteria as Cell Factories to Produce Plant Secondary Metabolites

    OpenAIRE

    Xue, Yong; He, Qingfang

    2015-01-01

    Cyanobacteria represent a promising platform for the production of plant secondary metabolites. Their capacity to express plant P450 proteins, which have essential functions in the biosynthesis of many plant secondary metabolites, makes cyanobacteria ideal for this purpose, and their photosynthetic capability allows cyanobacteria to grow with simple nutrient inputs. This review summarizes the advantages of using cyanobacteria to transgenically produce plant secondary metabolites. Some techniq...

  1. 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.

  2. Terpenoids and Their Biosynthesis in Cyanobacteria

    Directory of Open Access Journals (Sweden)

    Bagmi Pattanaik

    2015-01-01

    Full Text Available Terpenoids, or isoprenoids, are a family of compounds with great structural diversity which are essential for all living organisms. In cyanobacteria, they are synthesized from the methylerythritol-phosphate (MEP pathway, using glyceraldehyde 3-phosphate and pyruvate produced by photosynthesis as substrates. The products of the MEP pathway are the isomeric five-carbon compounds isopentenyl diphosphate and dimethylallyl diphosphate, which in turn form the basic building blocks for formation of all terpenoids. Many terpenoid compounds have useful properties and are of interest in the fields of pharmaceuticals and nutrition, and even potentially as future biofuels. The MEP pathway, its function and regulation, and the subsequent formation of terpenoids have not been fully elucidated in cyanobacteria, despite its relevance for biotechnological applications. In this review, we summarize the present knowledge about cyanobacterial terpenoid biosynthesis, both regarding the native metabolism and regarding metabolic engineering of cyanobacteria for heterologous production of non-native terpenoids.

  3. Terpenoids and Their Biosynthesis in Cyanobacteria

    Science.gov (United States)

    Pattanaik, Bagmi; Lindberg, Pia

    2015-01-01

    Terpenoids, or isoprenoids, are a family of compounds with great structural diversity which are essential for all living organisms. In cyanobacteria, they are synthesized from the methylerythritol-phosphate (MEP) pathway, using glyceraldehyde 3-phosphate and pyruvate produced by photosynthesis as substrates. The products of the MEP pathway are the isomeric five-carbon compounds isopentenyl diphosphate and dimethylallyl diphosphate, which in turn form the basic building blocks for formation of all terpenoids. Many terpenoid compounds have useful properties and are of interest in the fields of pharmaceuticals and nutrition, and even potentially as future biofuels. The MEP pathway, its function and regulation, and the subsequent formation of terpenoids have not been fully elucidated in cyanobacteria, despite its relevance for biotechnological applications. In this review, we summarize the present knowledge about cyanobacterial terpenoid biosynthesis, both regarding the native metabolism and regarding metabolic engineering of cyanobacteria for heterologous production of non-native terpenoids. PMID:25615610

  4. Color of cyanobacteria: some methodological aspects

    International Nuclear Information System (INIS)

    Prieto, Beatriz; Sanmartin, Patricia; Aira, Noelia; Silva, Benita

    2010-01-01

    Although the color of cyanobacteria is a very informative characteristic, no standardized protocol has, so far, been established for defining the color in an objective way, and, therefore, direct comparison of experimental results obtained by different research groups is not possible. In the present study, we used colorimetric measurements and conventional statistical tools to determine the effects on the measurement of the color of cyanobacteria, of the concentration of the microorganisms and their moisture content, as well as of the size of the target area and the minimum number of measurements. It was concluded that the color measurement is affected by every factor studied, but that this can be controlled for by making at least 10 consecutive measurements/9.62 cm 2 at different randomly selected points on the surface of filters completely covered by films of cyanobacteria in which the moisture contents are higher than 50%.

  5. Cyanobacteria: Promising biocatalysts for sustainable chemical production.

    Science.gov (United States)

    Knoot, Cory J; Ungerer, Justin; Wangikar, Pramod P; Pakrasi, Himadri B

    2018-04-06

    Cyanobacteria are photosynthetic prokaryotes showing great promise as biocatalysts for the direct conversion of CO 2 into fuels, chemicals, and other value-added products. Introduction of just a few heterologous genes can endow cyanobacteria with the ability to transform specific central metabolites into many end products. Recent engineering efforts have centered around harnessing the potential of these microbial biofactories for sustainable production of chemicals conventionally produced from fossil fuels. Here, we present an overview of the unique chemistry that cyanobacteria have been co-opted to perform. We highlight key lessons learned from these engineering efforts and discuss advantages and disadvantages of various approaches. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

  6. Occurrence of cyanobacteria genera in the Vaal Dam: implications ...

    African Journals Online (AJOL)

    The occurrence of cyanobacteria genera in the Vaal Dam was analysed and the factors that influence its dominance in the particular reservoir were also investigated. The study was motivated by the effects of the secondary metabolites of cyanobacteria genera on potable water production. Cyanobacteria genera have been ...

  7. Recruitment of bloom-forming cyanobacteria and its driving factors ...

    African Journals Online (AJOL)

    Based on most of the literature, this paper reviewed the progress made in following aspects: cognition to cyanobacteria recruitment, various traps for studying cyanobacteria recruitment in lakes, recruitment patterns of some species of cyanobacteria, and the driving factors for recruitment. Additionally, perspective studies of ...

  8. Study of cyanotoxins presence from experimental cyanobacteria concentrations using a new data mining methodology based on multivariate adaptive regression splines in Trasona reservoir (Northern Spain).

    Science.gov (United States)

    Garcia Nieto, P J; Sánchez Lasheras, F; de Cos Juez, F J; Alonso Fernández, J R

    2011-11-15

    There is an increasing need to describe cyanobacteria blooms since some cyanobacteria produce toxins, termed cyanotoxins. These latter can be toxic and dangerous to humans as well as other animals and life in general. It must be remarked that the cyanobacteria are reproduced explosively under certain conditions. This results in algae blooms, which can become harmful to other species if the cyanobacteria involved produce cyanotoxins. In this research work, the evolution of cyanotoxins in Trasona reservoir (Principality of Asturias, Northern Spain) was studied with success using the data mining methodology based on multivariate adaptive regression splines (MARS) technique. The results of the present study are two-fold. On one hand, the importance of the different kind of cyanobacteria over the presence of cyanotoxins in the reservoir is presented through the MARS model and on the other hand a predictive model able to forecast the possible presence of cyanotoxins in a short term was obtained. The agreement of the MARS model with experimental data confirmed the good performance of the same one. Finally, conclusions of this innovative research are exposed. Copyright © 2011 Elsevier B.V. All rights reserved.

  9. 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...

  10. 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...

  11. Convergent Evolution of Ergothioneine Biosynthesis in Cyanobacteria.

    Science.gov (United States)

    Liao, Cangsong; Seebeck, Florian P

    2017-11-02

    Biosynthesis of N-α-trimethyl-2-thiohistidine (ergothioneine) is a frequent trait in cyanobacteria. This sulfur compound may provide essential relief from oxidative stress related to oxygenic photosynthesis. The central steps in ergothioneine biosynthesis are catalyzed by a histidine methyltransferase and an iron-dependent sulfoxide synthase. In this report, we present evidence that some cyanobacteria recruited and adapted a sulfoxide synthase from a different biosynthetic pathway to make ergothioneine. The discovery of a second origin of ergothioneine production underscores the physiological importance of this metabolite and highlights the evolutionary malleability of the thiohistidine biosynthetic machinery. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. 14CO2 fixation pattern of cyanobacteria

    International Nuclear Information System (INIS)

    Erdmann, N.; Schiewer, U.

    1985-01-01

    The 14 CO 2 fixation pattern of three cyanobacteria in the light and dark were studied. Two different chromatographic methods widely used for separating labelled photosynthetic intermediates were compared. After ethanolic extraction, a rather uniform fixation pattern reflecting mainly the β-carboxylation pathway is obtained for all 3 species. Of the intermediates, glucosylglycerol is specific and high citrulline and low malate contents are fairly specific to cyanobacteria. The composition of the 14 CO 2 fixation pattern is hardly affected by changes in temperature or light intensity, but it is severely affected by changes in the water potential of the medium. (author)

  13. Scenario studies for algae production

    OpenAIRE

    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 productivity and energy consumption, while considering the uncertainty and complexity in such large-scale systems. In this thesis frameworks are developed to assess 1) the productivity during algae culti...

  14. Phthalate esters in marine algae

    OpenAIRE

    Gezgin, Tuncay; Güven, Kasim Cemal; Akçin, Göksel

    2001-01-01

    Abstract o-Phthalate esters as diethyl phthalate, dibutyl phthalate, di-isobutyl phthalate and diethylhexyl phthalate were identified at surface and inner part of algae collected in the Bosphorus, as Ulva lactuca, Enteromorpha linza, Cystoseria barbata, Pterocladia capillaceaeand Ceramium rubrum. The same esters were also detected in seawater samples taken from the same area. Thus parallelism in pollution was noted between the algae and the surrounding seawater,

  15. Optical researches for cyanobacteria bloom monitoring in Curonian Lagoon

    Science.gov (United States)

    Shirshin, Evgeny A.; Budylin, Gleb B.; Yakimov, Boris P.; Voloshina, Olga V.; Karabashev, Genrik S.; Evdoshenko, Marina A.; Fadeev, Victor V.

    2016-04-01

    Cyanobacteria bloom is a great ecological problem of Curonian Lagoon and Baltic Sea. The development of novel methods for the on-line control of cyanobacteria concentration and, moreover, for prediction of bloom spreading is of interest for monitoring the state of ecosystem. Here, we report the results of the joint application of hyperspectral measurements and remote sensing of Curonian Lagoon in July 2015 aimed at the assessment of cyanobacteria communities. We show that hyperspectral data allow on-line detection and qualitative estimation of cyanobacteria concentration, while the remote sensing data indicate the possibility of cyanobacteria bloom detection using the spectral features of upwelling irradiation.

  16. Using H2O2 treatments for the degradation of cyanobacteria and microcystins in a shallow hypertrophic reservoir.

    Science.gov (United States)

    Papadimitriou, Theodoti; Kormas, Konstantinos; Dionysiou, Dionysios D; Laspidou, Chrysi

    2016-11-01

    Toxins produced by cyanobacteria in freshwater ecosystems constitute a serious health risk worldwide for humans that may use the affected water bodies for recreation, drinking water, and/or irrigation. Cyanotoxins have also been deemed responsible for loss of animal life in many places around the world. This paper explores the effect of H 2 O 2 treatments on cyanobacteria and microcystins in natural samples from a hypertrophic reservoir in microcosm experiments. According to the results, cyanobacteria were more easily affected by H 2 O 2 than by other phytoplanktonic groups. This was shown by the increase in the fractions of chlorophyll-a (a proxy for phytoplankton) and chlorophyll-b (a proxy for green algae) over total phytoplankton pigments and the decrease in the fraction of phycocyanin (a proxy for cyanobacteria) over total phytoplankton pigments. Thus, while an overall increase in phytoplankton occurred, a preferential decrease in cyanobacteria was observed with H 2 O 2 treatments over a few hours. Moreover, significant degradation of total microcystins was observed under H 2 O 2 treatments, while more microcystins were degraded when UV radiation was used in combination with H 2 O 2 . The combination of H 2 O 2 and ultraviolet (UV) treatment in natural samples resulted in total microcystin concentrations that were below the World Health Organization limit for safe consumption of drinking water of 1 μg/L. Although further investigation into the effects of H 2 O 2 addition on ecosystem function must be performed, our results show that the application of H 2 O 2 could be a promising method for the degradation of microcystins in reservoirs and the reduction of public health risks related to the occurrence of harmful algal blooms.

  17. Summer heatwaves promote blooms of harmful cyanobacteria

    NARCIS (Netherlands)

    K.D Joehnk; J. Huisman; J. Sharples; B.P. Sommeijer (Ben); P.M. Visser (Petra); J.M. Stroom

    2008-01-01

    htmlabstractDense surface blooms of toxic cyanobacteria in eutrophic lakes may lead to mass mortalities of fish and birds, and provide a serious health threat for cattle, pets, and humans. It has been argued that global warming may increase the incidence of harmful algal blooms. Here, we report on a

  18. Summer heatwaves promote blooms of harmful cyanobacteria

    NARCIS (Netherlands)

    Jöhnk, K.D.; Huisman, J.; Sharples, J.; Sommeijer, B.; Visser, P.M.; Stroom, J.M.

    2008-01-01

    Dense surface blooms of toxic cyanobacteria in eutrophic lakes may lead to mass mortalities of fish and birds, and provide a serious health threat for cattle, pets, and humans. It has been argued that global warming may increase the incidence of harmful algal blooms. Here, we report on a lake

  19. Cyanobacteria of Greece: an annotated checklist

    Science.gov (United States)

    Ourailidis, Iordanis; Panou, Manthos; Pappas, Nikos

    2016-01-01

    Abstract Background The checklist of Greek Cyanobacteria was created in the framework of the Greek Taxon Information System (GTIS), an initiative of the LifeWatchGreece Research Infrastructure (ESFRI) that has resumed efforts to compile a complete checklist of species reported from Greece. This list was created from exhaustive search of the scientific literature of the last 60 years. All records of taxa known to occur in Greece were taxonomically updated. New information The checklist of Greek Cyanobacteria comprises 543 species, classified in 130 genera, 41 families, and 8 orders. The orders Synechococcales and Oscillatoriales have the highest number of species (158 and 153 species, respectively), whereas these two orders along with Nostocales and Chroococcales cover 93% of the known Greek cyanobacteria species. It is worth mentioning that 18 species have been initially described from Greek habitats. The marine epilithic Ammatoidea aegea described from Saronikos Gulf is considered endemic to this area. Our bibliographic review shows that Greece hosts a high diversity of cyanobacteria, suggesting that the Mediterranean area is also a hot spot for microbes. PMID:27956851

  20. Cyanobacteria of Greece: an annotated checklist.

    Science.gov (United States)

    Gkelis, Spyros; Ourailidis, Iordanis; Panou, Manthos; Pappas, Nikos

    2016-01-01

    The checklist of Greek Cyanobacteria was created in the framework of the Greek Taxon Information System (GTIS), an initiative of the LifeWatchGreece Research Infrastructure (ESFRI) that has resumed efforts to compile a complete checklist of species reported from Greece. This list was created from exhaustive search of the scientific literature of the last 60 years. All records of taxa known to occur in Greece were taxonomically updated. The checklist of Greek Cyanobacteria comprises 543 species, classified in 130 genera, 41 families, and 8 orders. The orders Synechococcales and Oscillatoriales have the highest number of species (158 and 153 species, respectively), whereas these two orders along with Nostocales and Chroococcales cover 93% of the known Greek cyanobacteria species. It is worth mentioning that 18 species have been initially described from Greek habitats. The marine epilithic Ammatoidea aegea described from Saronikos Gulf is considered endemic to this area. Our bibliographic review shows that Greece hosts a high diversity of cyanobacteria, suggesting that the Mediterranean area is also a hot spot for microbes.

  1. Determination of the Glycogen Content in Cyanobacteria.

    Science.gov (United States)

    De Porcellinis, Alice; Frigaard, Niels-Ulrik; Sakuragi, Yumiko

    2017-07-17

    Cyanobacteria accumulate glycogen as a major intracellular carbon and energy storage during photosynthesis. Recent developments in research have highlighted complex mechanisms of glycogen metabolism, including the diel cycle of biosynthesis and catabolism, redox regulation, and the involvement of non-coding RNA. At the same time, efforts are being made to redirect carbon from glycogen to desirable products in genetically engineered cyanobacteria to enhance product yields. Several methods are used to determine the glycogen contents in cyanobacteria, with variable accuracies and technical complexities. Here, we provide a detailed protocol for the reliable determination of the glycogen content in cyanobacteria that can be performed in a standard life science laboratory. The protocol entails the selective precipitation of glycogen from the cell lysate and the enzymatic depolymerization of glycogen to generate glucose monomers, which are detected by a glucose oxidase-peroxidase (GOD-POD) enzyme coupled assay. The method has been applied to Synechocystis sp. PCC 6803 and Synechococcus sp. PCC 7002, two model cyanobacterial species that are widely used in metabolic engineering. Moreover, the method successfully showed differences in the glycogen contents between the wildtype and mutants defective in regulatory elements or glycogen biosynthetic genes.

  2. Iron-Tolerant Cyanobacteria: Ecophysiology and Fingerprinting

    Science.gov (United States)

    Brown, I. I.; Mummey, D.; Lindsey, J.; McKay, D. S.

    2006-01-01

    Although the iron-dependent physiology of marine and freshwater cyanobacterial strains has been the focus of extensive study, very few studies dedicated to the physiology and diversity of cyanobacteria inhabiting iron-depositing hot springs have been conducted. One of the few studies that have been conducted [B. Pierson, 1999] found that cyanobacterial members of iron depositing bacterial mat communities might increase the rate of iron oxidation in situ and that ferrous iron concentrations up to 1 mM significantly stimulated light dependent consumption of bicarbonate, suggesting a specific role for elevated iron in photosynthesis of cyanobacteria inhabiting iron-depositing hot springs. Our recent studies pertaining to the diversity and physiology of cyanobacteria populating iron-depositing hot springs in Great Yellowstone area (Western USA) indicated a number of different isolates exhibiting elevated tolerance to Fe(3+) (up to 1 mM). Moreover, stimulation of growth was observed with increased Fe(3+) (0.02-0.4 mM). Molecular fingerprinting of unialgal isolates revealed a new cyanobacterial genus and species Chroogloeocystis siderophila, an unicellular cyanobacterium with significant EPS sheath harboring colloidal Fe(3+) from iron enriched media. Our preliminary data suggest that some filamentous species of iron-tolerant cyanobacteria are capable of exocytosis of iron precipitated in cytoplasm. Prior to 2.4 Ga global oceans were likely significantly enriched in soluble iron [Lindsay et al, 2003], conditions which are not conducive to growth of most contemporary oxygenic cyanobacteria. Thus, iron-tolerant CB may have played important physiological and evolutionary roles in Earths history.

  3. Grazing livestock are exposed to terrestrial cyanobacteria.

    Science.gov (United States)

    McGorum, Bruce C; Pirie, R Scott; Glendinning, Laura; McLachlan, Gerry; Metcalf, James S; Banack, Sandra A; Cox, Paul A; Codd, Geoffrey A

    2015-02-25

    While toxins from aquatic cyanobacteria are a well-recognised cause of disease in birds and animals, exposure of grazing livestock to terrestrial cyanobacteria has not been described. This study identified terrestrial cyanobacteria, predominantly Phormidium spp., in the biofilm of plants from most livestock fields investigated. Lower numbers of other cyanobacteria, microalgae and fungi were present on many plants. Cyanobacterial 16S rDNA, predominantly from Phormidium spp., was detected in all samples tested, including 6 plant washings, 1 soil sample and ileal contents from 2 grazing horses. Further work was performed to test the hypothesis that ingestion of cyanotoxins contributes to the pathogenesis of some currently unexplained diseases of grazing horses, including equine grass sickness (EGS), equine motor neuron disease (EMND) and hepatopathy. Phormidium population density was significantly higher on EGS fields than on control fields. The cyanobacterial neurotoxic amino acid 2,4-diaminobutyric acid (DAB) was detected in plant washings from EGS fields, but worst case scenario estimations suggested the dose would be insufficient to cause disease. Neither DAB nor the cyanobacterial neurotoxins β-N-methylamino-L-alanine and N-(2-aminoethyl) glycine were detected in neural tissue from 6 EGS horses, 2 EMND horses and 7 control horses. Phormidium was present in low numbers on plants where horses had unexplained hepatopathy. This study did not yield evidence linking known cyanotoxins with disease in grazing horses. However, further study is warranted to identify and quantify toxins produced by cyanobacteria on livestock fields, and determine whether, under appropriate conditions, known or unknown cyanotoxins contribute to currently unexplained diseases in grazing livestock.

  4. Response to variable light intensity in photoacclimated algae and cyanobacteria exposed to atrazine

    Energy Technology Data Exchange (ETDEWEB)

    Deblois, Charles P.; Dufresne, Karine [Department of Biological Sciences-TOXEN, Ecotoxicology of Aquatic Microorganisms Laboratory, Universite du Quebec a Montreal, Succ. Centre-Ville, Montreal, Quebec (Canada); Juneau, Philippe, E-mail: juneau.philippe@uqam.ca [Department of Biological Sciences-TOXEN, Ecotoxicology of Aquatic Microorganisms Laboratory, Universite du Quebec a Montreal, Succ. Centre-Ville, Montreal, Quebec (Canada)

    2013-01-15

    Atrazine is frequently detected in freshwater ecosystems exposed to agricultural waste waters and runoffs worldwide and it can affect non-target organisms (mainly photoautotrophic) and modify community structure. Meanwhile, light environment is known to vary between aquatic ecosystems, but also before and during the exposure to atrazine and these variations may modify the sensitivity to atrazine of photoautotroph organisms. In this study, 10 species of phytoplankton (chlorophytes, baccilariophytes and cyanophytes) acclimated to low or high light intensities were exposed to atrazine and light of different intensities to compare their combined effect. Our data showed that chlorophytes and baccilariophytes were more resistant to atrazine compared to cyanophytes for all light conditions. Atrazine was found to inhibit {Phi}{sup Prime }{sub M}, {Psi}{sub 0}, P{sub M} and non-photochemical quenching for all species indicating an effect on electron transport, primary production and photoregulation processes. These data also indicate a higher sensitivity of {Psi}{sub 0} (average {Psi}{sub 0}-EC{sub 50} of 91 {+-} 11 nM or 19.6 {+-} 0.9 {mu}g L{sup -1}) compared to {Phi}{sup Prime }{sub M} (average {Phi}{sup Prime }{sub M}-EC{sub 50} of 217 {+-} 19 nM or 46.8 {+-} 4.1 {mu}g L{sup -1}) and suggest that photoregulation processes activated in presence of light decrease the effect of atrazine. We also showed that increasing light intensity decreased {Phi}{sup Prime }{sub M}-EC{sub 50} in both low (except baccilariophytes) and high light acclimated conditions. Despite this similarity, most species acclimated to high light were found to have higher or similar {Phi}{sup Prime }{sub M}-EC{sub 50} compared to low light acclimated cells and thus, were less sensitive to atrazine in low light and high light environments. We concluded that an increase in the plastoquinone pool induced by acclimation to high light decreased the sensitivity to atrazine in phytoplankton and we hypothesized that the effect observed was the result of a dilution of atrazine toxicity through increased binding site availability (quinones) combined with increased photoregulation processes capacity.

  5. Reducing rice field algae and cyanobacteria abundance by altering phosphorus fertilizer applications

    Science.gov (United States)

    In California’s water seeded rice systems algal/cyanobacterial biomass can be a problem during rice establishment. Algal/cyanobacterial growth may be stimulated by phosphorus (P) additions in freshwater habitats, so we set up experiments to evaluate the effects of fertilizer P management on algal/cy...

  6. The role of algae and cyanobacteria in the production and release of odorants in water.

    Science.gov (United States)

    Lee, Jechan; Rai, Prabhat Kumar; Jeon, Young Jae; Kim, Ki-Hyun; Kwon, Eilhann E

    2017-08-01

    This review covers literatures pertaining to algal and cyanobacterial odor problems that have been published over the last five decades. Proper evaluation of algal and cyanobacterial odors may help establish removal strategies for hazardous metabolites while enhancing the recyclability of water. A bloom of microalgae is a sign of an anthropogenic disturbance in aquatic systems and can lead to diverse changes in ecosystems along with increased production of odorants. In general, because algal and cyanobacterial odors vary in chemistry and intensity according to blooming pattern, it is necessary to learn more about the related factors and processes (e.g., changes due to differences in taxa). This necessitates systematic and transdisciplinary approaches that require the cooperation of chemists, biologists, engineers, and policy makers. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Use of instrumental methods in the investigation of low temperature tolerance of soil algae and cyanobacteria

    Czech Academy of Sciences Publication Activity Database

    Lukešová, Alena; Worland, M. R.; Kaftan, David; Lukeš, Martin

    2004-01-01

    Roč. 3, č. 1 (2004), s. 82-85 ISSN 1336-1120 Grant - others:Evropská unie(XE) QLRI-CT--2001-01645 Institutional research plan: CEZ:AV0Z6066911 Keywords : cryomicroscopy * cryopreservation * differential scanning calorimetry Subject RIV: EH - Ecology, Behaviour

  8. Comparing the sensitivity of chlorophytes, cyanobacteria, and diatoms to major-use antibiotics.

    Science.gov (United States)

    Guo, Jiahua; Selby, Katherine; Boxall, Alistair B A

    2016-10-01

    The occurrence of antibiotic residues in the aquatic environment is an emerging concern. In contrast to daphnia and fish, algae are known to be particularly sensitive to antibiotic exposure. However, to date, a systematic evaluation of the sensitivity of different algal species to antibiotics has not been performed. The aim of the present study was therefore to explore the sensitivity of a battery of algal species toward antibiotic exposures. The present study investigated the growth inhibition effects of 3 major-use antibiotics, tylosin, lincomycin, and trimethoprim, on 7 algal species from the chlorophyte, cyanobacteria, and diatom groups. Based on median effective concentration (EC50) values, cyanobacteria (EC50 = 0.095-0.13 μmol/L) were found to be the most sensitive group to lincomycin followed by chlorophytes (EC50 = 7.36-225.73 μmol/L) and diatoms (EC50 > 225.73 μmol/L). Cyanobacteria were also the most sensitive group to tylosin (EC50 = 0.09-0.092 μmol/L), but, for this compound, diatoms (EC50 = 1.33-5.7 μmol/L) were more sensitive than chlorophytes (EC50 = 4.14-81.2 μmol/L). Diatoms were most sensitive to trimethoprim (EC50 = 7.36-74.61 μmol/L), followed by cyanobacteria (EC50 = 315.78-344.45 μmol/L), and chlorophytes (EC50 > 344.45 μmol/L) for trimethoprim. Although these results partly support the current approach to regulatory environmental risk assessment (whereby cyanobacterial species are recommended for use with antibiotic compounds), they indicate that for some antibiotics this group might not be the most appropriate test organism. It is therefore suggested that environmental risk assessments consider data on 3 algal groups (chlorophytes, cyanobacteria, and diatoms) and use test species from these groups, which are consistently found to be the most sensitive (Pseudokirchneriella subcapitata, Anabaena flos-aquae, and Navicula pelliculosa). Environ Toxicol Chem 2016;35:2587-2596. © 2016 SETAC.

  9. Physical data and biological data for algae, aquatic invertebrates, and fish from selected reaches on the Carson and Truckee rivers, Nevada and California, 1993-97

    Science.gov (United States)

    Lawrence, S.J.; Seiler, R.L.

    2002-01-01

    This report, a product of the National Water- Quality Assessment Program, is a compilation of physical data and biological data for algae, aquatic invertebrates, and fish collected in the Carson and Truckee River Basins, Nevada and California. Most of the data were collected between 1993 and 1996 at selected reaches on the Carson and Truckee Rivers. Algae and aquatic invertebrate samples were collected from cobble riffles, submerged woody-snag habitats, and from depositional areas such as pools. Between 1993 and 1996, fish and crayfish were collected from all wadeable habitats at each of seven basic-fixed sites using either electroshocking methods or seining. Additional fish and crayfish were collected at one site on the Truckee River in 1997. Fish were identified to species, measured for total and standard length, checked for anomalies, and weighed at the collection site. Fish were returned to the stream after measurements were taken. Measurements of water depth, stream velocity, determinations of substrate type and substrate embeddedness were made at each sampling site. Algae and aquatic invertebrate samples were sent to the U.S. Geological Survey National Water-Quality Laboratory for identification and enumeration. A total of 103 semi-quantitative and 55 qualitative algae samples were collected at 20 river reaches on the Carson and Truckee Rivers between 1993 and 1996. These samples represent algae in cobble riffles, on submerged woody snags, and on sediment surfaces in depositional areas. In those 158 samples, 514 algal species, varieties, or forms were identified. Of the 8 algal phyla represented, the diatoms (Phylum Bacillariophyta) were the most abundant with 351 species, varieties, or forms. The green algae (Phylum Chlorophyta) were next in abundance with 108 species, varieties, or forms followed by the blue-green algae (Phylum Cyanophyta) with 41 species, varieties, or forms. A total of 49 semi-quantitative aquatic invertebrate samples were collected at 27

  10. 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.

  11. Identifying key soil cyanobacteria easy to isolate and culture for arid soil restoration

    Science.gov (United States)

    Roncero-Ramos, Beatriz; Ángeles Muñoz-Martín, M.; Chamizo, Sonia; Román, Raúl; Rodriguez-Caballero, Emilio; Mateo, Pilar; Cantón, Yolanda

    2017-04-01

    Drylands represent an important fraction of the Earth land's surface. Low cover of vascular plants characterizes these regions, and the large open areas among plants are often colonized by cyanobacteria, mosses, lichens, algae, bryophytes, bacteria and fungi, known as biocrusts. Because these communities are on or within the soil surface, they contribute to improve physicochemical properties of the uppermost soil layers and have important effects on soil fertility and stability, so they could play an important role on soil restoration. Cyanobacteria appear to be a cross component of biocrusts and they have been demonstrated to enhance water availability, soil fertility (fixing atmospheric C and N), and soil aggregation (thanks to their filamentous morphology and the exopolysaccharides they excrete), and significantly reduce water and wind erosion. Besides, they are able to tolerate high temperatures and UV radiation. All these features convert cyanobacteria in pioneer organisms capable of colonizing degraded soils and may be crucial in facilitating the succession of more developed organisms such as vascular plants. Therefore, the use of native cyanobacteria, already adapted to site environmental conditions, could guarantee a successful restoration approach of degraded soils. However, previous to their application for soil restoration, the most representative species inhabiting these soils should be identified. The objective of this study was to identify (morphologically and genetically) and isolate representative native cyanobacteria species from arid soils in SE Spain, characterized for being easily isolated and cultured with the aim of using them to inoculate degraded arid soil. We selected two study areas in Almería, SE Spain, where biocrust cover most of the open spaces between plants: El Cautivo experimental site located in the Tabernas desert and a limestone quarry located at the southeastern edge of the Gádor massif. The first site is characterized by

  12. A novel ether-linked phytol-containing digalactosylglycerolipid in the marine green alga, Ulva pertusa

    International Nuclear Information System (INIS)

    Ishibashi, Yohei; Nagamatsu, Yusuke; Miyamoto, Tomofumi; Matsunaga, Naoyuki; Okino, Nozomu; Yamaguchi, Kuniko; Ito, Makoto

    2014-01-01

    Highlights: • Alkaline-resistant galactolipid, AEGL, was found in marine algae. • The sugar moiety of AEGL is identical to that of digalactosyldiacylglycerol. • AEGL is the first identified glycolipid that possesses an ether-linked phytol. • AEGL is ubiquitously distributed in green, red and brown marine algae. - Abstract: Galactosylglycerolipids (GGLs) and chlorophyll are characteristic components of chloroplast in photosynthetic organisms. Although chlorophyll is anchored to the thylakoid membrane by phytol (tetramethylhexadecenol), this isoprenoid alcohol has never been found as a constituent of GGLs. We here described a novel GGL, in which phytol was linked to the glycerol backbone via an ether linkage. This unique GGL was identified as an Alkaline-resistant and Endogalactosylceramidase (EGALC)-sensitive GlycoLipid (AEGL) in the marine green alga, Ulva pertusa. EGALC is an enzyme that is specific to the R-Galα/β1-6Galβ1-structure of galactolipids. The structure of U. pertusa AEGL was determined following its purification to 1-O-phytyl-3-O-Galα1-6Galβ1-sn-glycerol by mass spectrometric and nuclear magnetic resonance analyses. AEGLs were ubiquitously distributed in not only green, but also red and brown marine algae; however, they were rarely detected in terrestrial plants, eukaryotic phytoplankton, or cyanobacteria

  13. A novel ether-linked phytol-containing digalactosylglycerolipid in the marine green alga, Ulva pertusa

    Energy Technology Data Exchange (ETDEWEB)

    Ishibashi, Yohei; Nagamatsu, Yusuke [Department of Bioscience and Biotechnology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581 (Japan); Miyamoto, Tomofumi [Graduate School of Pharmaceutical Sciences, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582 (Japan); Matsunaga, Naoyuki; Okino, Nozomu; Yamaguchi, Kuniko [Department of Bioscience and Biotechnology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581 (Japan); Ito, Makoto, E-mail: makotoi@agr.kyushu-u.ac.jp [Department of Bioscience and Biotechnology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581 (Japan)

    2014-10-03

    Highlights: • Alkaline-resistant galactolipid, AEGL, was found in marine algae. • The sugar moiety of AEGL is identical to that of digalactosyldiacylglycerol. • AEGL is the first identified glycolipid that possesses an ether-linked phytol. • AEGL is ubiquitously distributed in green, red and brown marine algae. - Abstract: Galactosylglycerolipids (GGLs) and chlorophyll are characteristic components of chloroplast in photosynthetic organisms. Although chlorophyll is anchored to the thylakoid membrane by phytol (tetramethylhexadecenol), this isoprenoid alcohol has never been found as a constituent of GGLs. We here described a novel GGL, in which phytol was linked to the glycerol backbone via an ether linkage. This unique GGL was identified as an Alkaline-resistant and Endogalactosylceramidase (EGALC)-sensitive GlycoLipid (AEGL) in the marine green alga, Ulva pertusa. EGALC is an enzyme that is specific to the R-Galα/β1-6Galβ1-structure of galactolipids. The structure of U. pertusa AEGL was determined following its purification to 1-O-phytyl-3-O-Galα1-6Galβ1-sn-glycerol by mass spectrometric and nuclear magnetic resonance analyses. AEGLs were ubiquitously distributed in not only green, but also red and brown marine algae; however, they were rarely detected in terrestrial plants, eukaryotic phytoplankton, or cyanobacteria.

  14. Experimental validation of a nonequilibrium model of CO2 fluxes between gas, liquid medium, and algae in a flat-panel photobioreactor

    Czech Academy of Sciences Publication Activity Database

    Nedbal, Ladislav; Červený, Jan; Keren, N.; Kaplan, A.

    2010-01-01

    Roč. 37, č. 12 (2010), s. 1319-1326 ISSN 1367-5435 R&D Projects: GA ČR GA206/09/1284 Institutional research plan: CEZ:AV0Z60870520 Keywords : algae * carbon dioxide * cyanobacteria * mathematical model * photosynthesis Subject RIV: EH - Ecology, Behaviour Impact factor: 2.416, year: 2010 http://www.springerlink.com/content/a2133tn14581366g/

  15. 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.

  16. 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.

  17. Indigenous algae: Potential factories for biodiesel production

    CSIR Research Space (South Africa)

    Maharajh, Dheepak M

    2008-11-01

    Full Text Available advantages. Approximately 30% of South African environments favourable for isolating algae have been sampled. Samples were enriched, purified and assessed for lipid content, resulting in a database of indigenous algae. Positive isolates were grown under...

  18. 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)

  19. Uncovering Potential Applications of Cyanobacteria and Algal Metabolites in Biology, Agriculture and Medicine: Current Status and Future Prospects

    Science.gov (United States)

    Singh, Rachana; Parihar, Parul; Singh, Madhulika; Bajguz, Andrzej; Kumar, Jitendra; Singh, Samiksha; Singh, Vijay P.; Prasad, Sheo M.

    2017-01-01

    Cyanobacteria and algae having complex photosynthetic systems can channelize absorbed solar energy into other forms of energy for production of food and metabolites. In addition, they are promising biocatalysts and can be used in the field of “white biotechnology” for enhancing the sustainable production of food, metabolites, and green energy sources such as biodiesel. In this review, an endeavor has been made to uncover the significance of various metabolites like phenolics, phytoene/terpenoids, phytols, sterols, free fatty acids, photoprotective compounds (MAAs, scytonemin, carotenoids, polysaccharides, halogenated compounds, etc.), phytohormones, cyanotoxins, biocides (algaecides, herbicides, and insecticides) etc. Apart from this, the importance of these metabolites as antibiotics, immunosuppressant, anticancer, antiviral, anti-inflammatory agent has also been discussed. Metabolites obtained from cyanobacteria and algae have several biotechnological, industrial, pharmaceutical, and cosmetic uses which have also been discussed in this review along with the emerging technology of their harvesting for enhancing the production of compounds like bioethanol, biofuel etc. at commercial level. In later sections, we have discussed genetically modified organisms and metabolite production from them. We have also briefly discussed the concept of bioprocessing highlighting the functioning of companies engaged in metabolites production as well as their cost effectiveness and challenges that are being addressed by these companies. PMID:28487674

  20. Uncovering Potential Applications of Cyanobacteria and Algal Metabolites in Biology, Agriculture and Medicine: Current Status and Future Prospects

    Directory of Open Access Journals (Sweden)

    Vijay P. Singh

    2017-04-01

    Full Text Available Cyanobacteria and algae having complex photosynthetic systems can channelize absorbed solar energy into other forms of energy for production of food and metabolites. In addition, they are promising biocatalysts and can be used in the field of “white biotechnology” for enhancing the sustainable production of food, metabolites, and green energy sources such as biodiesel. In this review, an endeavor has been made to uncover the significance of various metabolites like phenolics, phytoene/terpenoids, phytols, sterols, free fatty acids, photoprotective compounds (MAAs, scytonemin, carotenoids, polysaccharides, halogenated compounds, etc., phytohormones, cyanotoxins, biocides (algaecides, herbicides, and insecticides etc. Apart from this, the importance of these metabolites as antibiotics, immunosuppressant, anticancer, antiviral, anti-inflammatory agent has also been discussed. Metabolites obtained from cyanobacteria and algae have several biotechnological, industrial, pharmaceutical, and cosmetic uses which have also been discussed in this review along with the emerging technology of their harvesting for enhancing the production of compounds like bioethanol, biofuel etc. at commercial level. In later sections, we have discussed genetically modified organisms and metabolite production from them. We have also briefly discussed the concept of bioprocessing highlighting the functioning of companies engaged in metabolites production as well as their cost effectiveness and challenges that are being addressed by these companies.

  1. Planktonic cyanobacteria of the tropical karstic lake Lagartos from the Yucatan Peninsula, Mexico.

    Science.gov (United States)

    Valadez, Francisco; Rosiles-González, Gabriela; Almazán-Becerril, Antonio; Merino-Ibarra, Martin

    2013-06-01

    The tropical karstic lakes on the Mexican Caribbean Sea coast are numerous. However, there is an enormous gap of knowledge about their limnological conditions and micro-algae communities. In the present study, surface water samples were collected monthly from November 2007 to September 2008 to provide taxonomical composition and biovolume of planktonic cyanobacteria of the lake Lagartos from State of Quintana Roo, Mexico. Water temperature, pH, conductivity, salinity, soluble reactive phosphorus (SRP), dissolved inorganic nitrogen (DIN), and soluble reactive silica (SRSi) levels were also analyzed. A total of 22 species were identified. Chroococcales and Oscillatoriales dominated the phytoplankton assemblages during the study period. Chroococcus pulcherrimus, Coelosphaerium confertum, Cyanodyction iac, Phormidium pachydermaticum and Planktolyngbya contorta were recorded for the first time in Mexico. A surplus of DIN (mean value of 42.7 microM) and low concentrations of SRP (mean value of 1.0 microM) promoted the enhanced growth and bloom formation of cyanobacteria. The mean biovolume was 3.22 x 10(8) microm3/mL, and two biovolume peaks were observed; the first was dominated by Microcystis panniformis in November 2007 (7.40 x 10(8) microm3/mL), and the second was dominated by Oscillatoriaprinceps in April 2008 (6.55 x 10(8) microm3/mL). Water quality data, nitrates enrichment, and trophic state based on biovolume, indicated that Lagartos is a hyposaline, secondarily phosphorus-limited, and eutrophic lake, where the cyanobacteria flora was composed mainly by non-heterocystous groups.

  2. Planktonic Cyanobacteria of the tropical karstic lake Lagartos from the Yucatan Peninsula, Mexico

    Directory of Open Access Journals (Sweden)

    Francisco Valadez

    2013-06-01

    Full Text Available The tropical karstic lakes on the Mexican Caribbean Sea coast are numerous. However, there is an enormous gap of knowledge about their limnological conditions and micro-algae communities. In the present study, surface water samples were collected monthly from November 2007 to September 2008 to provide taxonomical composition and biovolume of planktonic cyanobacteria of the lake Lagartos from State of Quintana Roo, Mexico. Water temperature, pH, conductivity, salinity, soluble reactive phosphorus (SRP, dissolved inorganic nitrogen (DIN, and soluble reactive silica (SRSi levels were also analyzed. A total of 22 species were identified. Chroococcales and Oscillatoriales dominated the phytoplankton assemblages during the study period. Chroococcus pulcherrimus, Coelosphaerium confertum, Cyanodyction iac, Phormidium pachydermaticum and Planktolyngbya contorta were recorded for the first time in Mexico. A surplus of DIN (mean value of 42.7µM and low concentrations of SRP (mean value of 1.0µM promoted the enhanced growth and bloom formation of cyanobacteria. The mean biovolume was 3.22X10(8µm³/mL, and two biovolume peaks were observed; the first was dominated by Microcystis panniformis in November 2007 (7.40X10(8µm³/mL, and the second was dominated by Oscillatoria princeps in April 2008 (6.55X10(8µm³/mL. Water quality data, nitrates enrichment, and trophic state based on biovolume, indicated that Lagartos is a hyposaline, secondarily phosphorus-limited, and eutrophic lake, where the cyanobacteria flora was composed mainly by non-heterocystous groups.

  3. An investigation into the kinetics and mechanism of the removal of cyanobacteria by extract of Ephedra equisetina root.

    Directory of Open Access Journals (Sweden)

    Rong Yan

    Full Text Available An aqueous extract of Ephedra equisetina root was found to induce cyanobacterial cell death. The extract displayed no negative effects on the fish populations but instead, improved the habitat conditions for the growth of macrophytes, zooplankton and bacteria because the inhibiting effects of the extracts on cyanobacteria helped clear up the water column. The removal kinetics of cyanobacteria by E. equisetina extract appears to be a first order process with the rate constant being extract-dose-dependent. Compounds including the flavonoids found in E. equisetina root kill the cyanobacteria in vitro at a dose of 5.0 µg extract per 100 mL water or above. The extract constituents act to disrupt the thylakoid membrane, interrupt the electronic transport, decrease the effective quantum yield, and eventually lead to the failure of photosynthesis in Microcystis aeruginosa. This study presents an easily-deployed, natural and promising approach for controlling cyanobacterial blooms as an emergency measure, and also provides insight into the dynamics and mechanism of the extract consisting of multiple compounds synergistically removing algae.

  4. Unicellular cyanobacteria with a new mode of life: the lack of photosynthetic oxygen evolution allows nitrogen fixation to proceed.

    Science.gov (United States)

    Bothe, Hermann; Tripp, H James; Zehr, Jonathan P

    2010-10-01

    Some unicellular N(2)-fixing cyanobacteria have recently been found to lack a functional photosystem II of photosynthesis. Such organisms, provisionally termed UCYN-A, of the oceanic picoplanktion are major contributors to the global marine N-input by N(2)-fixation. Since their photosystem II is inactive, they can perform N(2)-fixation during the day. UCYN-A organisms cannot be cultivated as yet. Their genomic analysis indicates that they lack genes coding for enzymes of the Calvin cycle, the tricarboxylic acid cycle and for the biosynthesis of several amino acids. The carbon source in the ocean that allows them to thrive in such high abundance has not been identified. Their genomic analysis implies that they metabolize organic carbon by a new mode of life. These unicellular N(2)-fixing cyanobacteria of the oceanic picoplankton are evolutionarily related to spheroid bodies present in diatoms of the family Epithemiaceae, such as Rhopalodia gibba. More recently, spheroid bodies were ultimately proven to be related to cyanobacteria and to express nitrogenase. They have been reported to be completely inactive in all photosynthetic reactions despite the presence of thylakoids. Sequence data show that R. gibba and its spheroid bodies are an evolutionarily young symbiosis that might serve as a model system to unravel early events in the evolution of chloroplasts. The cell metabolism of UCYN-A and the spheroid bodies may be related to that of the acetate photoassimilating green alga Chlamydobotrys.

  5. Electricity generation from digitally printed cyanobacteria.

    Science.gov (United States)

    Sawa, Marin; Fantuzzi, Andrea; Bombelli, Paolo; Howe, Christopher J; Hellgardt, Klaus; Nixon, Peter J

    2017-11-06

    Microbial biophotovoltaic cells exploit the ability of cyanobacteria and microalgae to convert light energy into electrical current using water as the source of electrons. Such bioelectrochemical systems have a clear advantage over more conventional microbial fuel cells which require the input of organic carbon for microbial growth. However, innovative approaches are needed to address scale-up issues associated with the fabrication of the inorganic (electrodes) and biological (microbe) parts of the biophotovoltaic device. Here we demonstrate the feasibility of using a simple commercial inkjet printer to fabricate a thin-film paper-based biophotovoltaic cell consisting of a layer of cyanobacterial cells on top of a carbon nanotube conducting surface. We show that these printed cyanobacteria are capable of generating a sustained electrical current both in the dark (as a 'solar bio-battery') and in response to light (as a 'bio-solar-panel') with potential applications in low-power devices.

  6. Pathological effects of cyanobacteria on sea fans in southeast Florida.

    Science.gov (United States)

    Kiryu, Y; Landsberg, J H; Peters, E C; Tichenor, E; Burleson, C; Perry, N

    2015-07-01

    In early August 2008, observations by divers indicated that sea fans, particularly Gorgonia ventalina, Gorgonia flabellum, and Iciligorgia schrammi, were being covered by benthic filamentous cyanobacteria. From August 2008 through January 2009 and again in April 2009, tissue samples from a targeted G. ventalina colony affected by cyanobacteria and from a nearby, apparently healthy (without cyanobacteria) control colony, were collected monthly for histopathological examination. The primary cellular response of the sea fan to overgrowth by cyanobacteria was an increase in the number of acidophilic amoebocytes (with their granular contents dispersed) that were scattered throughout the coenenchyme tissue. Necrosis of scleroblasts and zooxanthellae and infiltration of degranulated amoebocytes were observed in the sea fan surface tissues at sites overgrown with cyanobacteria. Fungal hyphae in the axial skeleton were qualitatively more prominent in cyanobacteria-affected sea fans than in controls. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Ionizing radiation and photosynthetic ability of cyanobacteria

    International Nuclear Information System (INIS)

    Agarwal, Rachna; Sainis, Jayashree K.

    2006-01-01

    Unicellular photoautotrophic cyanobacteria, Anacystis nidulans when exposed to lethal dose of 1.5 kGy of 60 Co γ- radiation (D 10 = 257.32 Gy) were as effective photosynthetical as unirradiated controls immediately after irradiation although level of ROS was higher by several magnitudes in these irradiated cells. The results suggested the preservation of the functional integrity of thylakoids even after exposure to lethal dose of ionizing radiation. (author)

  8. Light-dependent electrogenic activity of cyanobacteria.

    Directory of Open Access Journals (Sweden)

    John M Pisciotta

    2010-05-01

    Full Text Available Cyanobacteria account for 20-30% of Earth's primary photosynthetic productivity and convert solar energy into biomass-stored chemical energy at the rate of approximately 450 TW [1]. These single-cell microorganisms are resilient predecessors of all higher oxygenic phototrophs and can be found in self-sustaining, nitrogen-fixing communities the world over, from Antarctic glaciers to the Sahara desert [2].Here we show that diverse genera of cyanobacteria including biofilm-forming and pelagic strains have a conserved light-dependent electrogenic activity, i.e. the ability to transfer electrons to their surroundings in response to illumination. Naturally-growing biofilm-forming photosynthetic consortia also displayed light-dependent electrogenic activity, demonstrating that this phenomenon is not limited to individual cultures. Treatment with site-specific inhibitors revealed the electrons originate at the photosynthetic electron transfer chain (P-ETC. Moreover, electrogenic activity was observed upon illumination only with blue or red but not green light confirming that P-ETC is the source of electrons. The yield of electrons harvested by extracellular electron acceptor to photons available for photosynthesis ranged from 0.05% to 0.3%, although the efficiency of electron harvesting likely varies depending on terminal electron acceptor.The current study illustrates that cyanobacterial electrogenic activity is an important microbiological conduit of solar energy into the biosphere. The mechanism responsible for electrogenic activity in cyanobacteria appears to be fundamentally different from the one exploited in previously discovered electrogenic bacteria, such as Geobacter, where electrons are derived from oxidation of organic compounds and transported via a respiratory electron transfer chain (R-ETC [3], [4]. The electrogenic pathway of cyanobacteria might be exploited to develop light-sensitive devices or future technologies that convert solar

  9. Evolution of photorespiration from cyanobacteria to land plants, considering protein phylogenies and acquisition of carbon concentrating mechanisms.

    Science.gov (United States)

    Hagemann, Martin; Kern, Ramona; Maurino, Veronica G; Hanson, David T; Weber, Andreas P M; Sage, Rowan F; Bauwe, Hermann

    2016-05-01

    Photorespiration and oxygenic photosynthesis are intimately linked processes. It has been shown that under the present day atmospheric conditions cyanobacteria and all eukaryotic phototrophs need functional photorespiration to grow autotrophically. The question arises as to when this essential partnership evolved, i.e. can we assume a coevolution of both processes from the beginning or did photorespiration evolve later to compensate for the generation of 2-phosphoglycolate (2PG) due to Rubisco's oxygenase reaction? This question is mainly discussed here using phylogenetic analysis of proteins involved in the 2PG metabolism and the acquisition of different carbon concentrating mechanisms (CCMs). The phylogenies revealed that the enzymes involved in the photorespiration of vascular plants have diverse origins, with some proteins acquired from cyanobacteria as ancestors of the chloroplasts and others from heterotrophic bacteria as ancestors of mitochondria in the plant cell. Only phosphoglycolate phosphatase was found to originate from Archaea. Notably glaucophyte algae, the earliest branching lineage of Archaeplastida, contain more photorespiratory enzymes of cyanobacterial origin than other algal lineages or land plants indicating a larger initial contribution of cyanobacterial-derived proteins to eukaryotic photorespiration. The acquisition of CCMs is discussed as a proxy for assessing the timing of periods when photorespiratory activity may have been enhanced. The existence of CCMs also had marked influence on the structure and function of photorespiration. Here, we discuss evidence for an early and continuous coevolution of photorespiration, CCMs and photosynthesis starting from cyanobacteria via algae, to land plants. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  10. 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…

  11. 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

  12. Cyanobacteria and cyanotoxins in freshwaters of Uruguay

    Directory of Open Access Journals (Sweden)

    Sylvia Bonilla

    2015-12-01

    Full Text Available Cyanobacterial blooms are a worldwide environmental problem. This phenomenon is typically associated with eutrophication (nutrient enrichment and changes in hydrology. In this study we analysed the distribution of planktonic cyanobacteria in Uruguay and their toxins (microcystin, saxitoxin and cylindrospermopsin, working with an interagency team (OSE, DINAMA, IM, University of the Republic and IIBCE. An historical data base (n = 3061 for 64 ecosystems, years 1980-2014 was generated. Differences between lotic and lentic ecosystems were found in terms of chlorophyll a and nutrient concentrations, usually indicating eutrophication. Two geo-referenced maps for the country were generated with cyanobacteria biomass indicators and the most relevant toxin (microcystin, according to risk levels suggested by the World Health Organization for recreational waters. The areas of greatest risk of exposure were the reservoirs of large rivers (Uruguay and Río Negro and Río de la Plata beaches. In the second part of the study, up to 20 mg L-1of microcystin was quantified in bloom (scum samples, as well as the presence of genes that suggest more microcystin varieties, potentially with greater toxicity. This study provides basic information about the distribution of cyanobacteria in Uruguayan freshwaters that will be useful for national monitoring programs and scientific research.

  13. Metabolic engineering tools in model cyanobacteria.

    Science.gov (United States)

    Carroll, Austin L; Case, Anna E; Zhang, Angela; Atsumi, Shota

    2018-03-26

    Developing sustainable routes for producing chemicals and fuels is one of the most important challenges in metabolic engineering. Photoautotrophic hosts are particularly attractive because of their potential to utilize light as an energy source and CO 2 as a carbon substrate through photosynthesis. Cyanobacteria are unicellular organisms capable of photosynthesis and CO 2 fixation. While engineering in heterotrophs, such as Escherichia coli, has result in a plethora of tools for strain development and hosts capable of producing valuable chemicals efficiently, these techniques are not always directly transferable to cyanobacteria. However, recent efforts have led to an increase in the scope and scale of chemicals that cyanobacteria can produce. Adaptations of important metabolic engineering tools have also been optimized to function in photoautotrophic hosts, which include Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-Cas9, 13 C Metabolic Flux Analysis (MFA), and Genome-Scale Modeling (GSM). This review explores innovations in cyanobacterial metabolic engineering, and highlights how photoautotrophic metabolism has shaped their development. Copyright © 2018 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

  14. Advances in Metabolic Engineering of Cyanobacteria for Photosynthetic Biochemical Production

    OpenAIRE

    Lai, Martin C.; Lan, Ethan I.

    2015-01-01

    Engineering cyanobacteria into photosynthetic microbial cell factories for the production of biochemicals and biofuels is a promising approach toward sustainability. Cyanobacteria naturally grow on light and carbon dioxide, bypassing the need of fermentable plant biomass and arable land. By tapping into the central metabolism and rerouting carbon flux towards desirable compound production, cyanobacteria are engineered to directly convert CO2 into various chemicals. This review discusses the d...

  15. Mercury analysis of acid- and alkaline-reduced biological samples: identification of meta-cinnabar as the major biotransformed compound in algae.

    Science.gov (United States)

    Kelly, David; Budd, Kenneth; Lefebvre, Daniel D

    2006-01-01

    The biotransformation of Hg(II) in pH-controlled and aerated algal cultures was investigated. Previous researchers have observed losses in Hg detection in vitro with the addition of cysteine under acid reduction conditions in the presence of SnCl2. They proposed that this was the effect of Hg-thiol complexing. The present study found that cysteine-Hg, protein and nonprotein thiol chelates, and nucleoside chelates of Hg were all fully detectable under acid reduction conditions without previous digestion. Furthermore, organic (R-Hg) mercury compounds could not be detected under either the acid or alkaline reduction conditions, and only beta-HgS was detected under alkaline and not under acid SnCl2 reduction conditions. The blue-green alga Limnothrix planctonica biotransformed the bulk of Hg(II) applied as HgCl2 into a form with the analytical properties of beta-HgS. Similar results were obtained for the eukaryotic alga Selenastrum minutum. No evidence for the synthesis of organomercurials such as CH3Hg+ was obtained from analysis of either airstream or biomass samples under the aerobic conditions of the study. An analytical procedure that involved both acid and alkaline reduction was developed. It provides the first selective method for the determination of beta-HgS in biological samples. Under aerobic conditions, Hg(II) is biotransformed mainly into beta-HgS (meta-cinnabar), and this occurs in both prokaryotic and eukaryotic algae. This has important implications with respect to identification of mercury species and cycling in aquatic habitats.

  16. A Review Study on Macrolides Isolated from Cyanobacteria.

    Science.gov (United States)

    Wang, Mengchuan; Zhang, Jinrong; He, Shan; Yan, Xiaojun

    2017-04-26

    Cyanobacteria are rich sources of structurally-diverse molecules with promising pharmacological activities. Marine cyanobacteria have been proven to be true producers of some significant bioactive metabolites from marine invertebrates. Macrolides are a class of bioactive compounds isolated from marine organisms, including marine microorganisms in particular. The structural characteristics of macrolides from cyanobacteria mainly manifest in the diversity of carbon skeletons, complexes of chlorinated thiazole-containing molecules and complex spatial configuration. In the present work, we systematically reviewed the structures and pharmacological activities of macrolides from cyanobacteria. Our data would help establish an effective support system for the discovery and development of cyanobacterium-derived macrolides.

  17. Proteomic analysis of post translational modifications in cyanobacteria.

    Science.gov (United States)

    Xiong, Qian; Chen, Zhuo; Ge, Feng

    2016-02-16

    Cyanobacteria are a diverse group of Gram-negative bacteria and the only prokaryotes capable of oxygenic photosynthesis. Recently, cyanobacteria have attracted great interest due to their crucial roles in global carbon and nitrogen cycles and their ability to produce clean and renewable biofuels. To survive in various environmental conditions, cyanobacteria have developed a complex signal transduction network to sense environmental signals and implement adaptive changes. The post-translational modifications (PTMs) systems play important regulatory roles in the signaling networks of cyanobacteria. The systematic investigation of PTMs could contribute to the comprehensive description of protein species and to elucidate potential biological roles of each protein species in cyanobacteria. Although the proteomic studies of PTMs carried out in cyanobacteria were limited, these data have provided clues to elucidate their sophisticated sensing mechanisms that contribute to their evolutionary and ecological success. This review aims to summarize the current status of PTM studies and recent publications regarding PTM proteomics in cyanobacteria, and discuss the novel developments and applications for the analysis of PTMs in cyanobacteria. Challenges, opportunities and future perspectives in the proteomics studies of PTMs in cyanobacteria are also discussed. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Optical propagation analysis in photobioreactor measurements on cyanobacteria

    Science.gov (United States)

    Fanjul-Vélez, F.; Arce-Diego, J. L.

    2017-12-01

    Biotechnology applications are nowadays increasing in many areas, from agriculture to biochemistry, or even biomedicine. Knowledge on biological processes is becoming essential in order to be able to adequately estimate and control the production of these elements. Cyanobacteria present the capability of producing oxygen and biomass, from CO2 and light irradiation. Therefore, they could be fundamental for human subsistence in adverse environments, as basic needs of breathing and food would be guaranteed. Cyanobacteria cultivation, as other microorganisms, is carried out in photo-bioreactors. The adequate design of photobioreactors greatly influences elements production throughput. This design includes optical illumination and optical measurement of cyanobacteria growth. In this work an analysis of optical measurement of cyanobacteria growth in a photobioreactor is made. As cyanobacteria are inhomogeneous elements, the influence of light scattering is significant. Several types of cyanobacteria are considered, as long as several spatial profiles and irradiances of the incident light. Depending on cyanobacteria optical properties, optical distribution of transmitted light can be estimated. These results allow an appropriate consideration, in the optical design, of the relationship between detected light and cyanobacteria growth. As a consequence, the most adequate conditions of elements production from cyanobacteria could be estimated.

  19. 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...

  20. Large-scale bioprospecting of cyanobacteria, micro- and macroalgae from the Aegean Sea.

    Science.gov (United States)

    Montalvão, Sofia; Demirel, Zeliha; Devi, Prabha; Lombardi, Valter; Hongisto, Vesa; Perälä, Merja; Hattara, Johannes; Imamoglu, Esra; Tilvi, Supriya Shet; Turan, Gamze; Dalay, Meltem Conk; Tammela, Päivi

    2016-05-25

    Marine organisms constitute approximately one-half of the total global biodiversity, being rich reservoirs of structurally diverse biofunctional components. The potential of cyanobacteria, micro- and macroalgae as sources of antimicrobial, antitumoral, anti-inflammatory, and anticoagulant compounds has been reported extensively. Nonetheless, biological activities of marine fauna and flora of the Aegean Sea have remained poorly studied when in comparison to other areas of the Mediterranean Sea. In this study, we screened the antimicrobial, antifouling, anti-inflammatory and anticancer potential of in total 98 specimens collected from the Aegean Sea. Ethanol extract of diatom Amphora cf capitellata showed the most promising antimicrobial results against Candida albicans while the extract of diatom Nitzschia communis showed effective results against Gram-positive bacterium, S. aureus. Extracts from the red alga Laurencia papillosa and from three Cystoseira species exhibited selective antiproliferative activity against cancer cell lines and an extract from the brown alga Dilophus fasciola showed the highest anti-inflammatory activity as measured in primary microglial and astrocyte cell cultures as well as by the reduction of proinflammatory cytokines. In summary, our study demonstrates that the Aegean Sea is a rich source of species that possess interesting potential for developing industrial applications. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Effect of Small-Scale Turbulence on the Physiology and Morphology of Two Bloom-Forming Cyanobacteria.

    Science.gov (United States)

    Xiao, Yan; Li, Zhe; Li, Chao; Zhang, Zhen; Guo, Jinsong

    2016-01-01

    The main goal of the present work is to test the hypothesis that small-scale turbulence affected physiological activities and the morphology of cyanobacteria in high turbulence environments. Using quantified turbulence in a stirring device, we conducted one set of experiments on cultures of two strains of cyanobacteria with different phenotypes; i.e., unicellular Microcystis flos-aquae and colonial Anabaena flos-aquae. The effect of small-scale turbulence examined varied from 0 to 8.01×10-2 m2s-3, covering the range of turbulence intensities experienced by cyanobacteria in the field. The results of photosynthesis activity and the cellular chlorophyll a in both strains did not change significantly among the turbulence levels, indicating that the potential indirect effects of a light regime under the gradient of turbulent mixing could be ignored. However, the experiments demonstrated that small-scale turbulence significantly modulated algal nutrient uptake and growth in comparison to the stagnant control. Cellular N and C of the two stains showed approximately the same responses, resulting in a similar pattern of C/N ratios. Moreover, the change in the phosphate uptake rate was similar to that of growth in two strains, which implied that growth characteristic responses to turbulence may be dependent on the P strategy, which was correlated with accumulation of polyphosphate. Additionally, our results also showed the filament length of A. flos-aquae decreased in response to high turbulence, which could favor enhancement of the nutrient uptake. These findings suggested that both M. flos-aquae and A. flos-aquae adjust their growth rates in response to turbulence levels in the ways of asynchronous cellular stoichiometry of C, N, and P, especially the phosphorus strategy, to improve the nutrient application efficiency. The fact that adaptation strategies of cyanobacteria diversely to turbulence depending on their physiological conditions presents a good example to

  2. Endosymbiotic heterocystous cyanobacteria synthesize different heterocyst glycolipids than free-living heterocystous cyanobacteria

    NARCIS (Netherlands)

    Schouten, S.; Villareal, T.A.; Hopmans, E.C.; Mets, A.; Swanson, K.M.; Sinninghe Damsté, J.S.

    2013-01-01

    The heterocysts of limnetic nitrogen-fixing filamentous cyanobacteria contain unique glycolipids in their cell wall that create the distinctive gas impermeability of the heterocyst cell wall as well as serve as biomarker lipids for these microbes. It has been assumed that marine free-living and

  3. Oxygen and temperature in relation to nitrogen fixation in cyanobacteria: In the daily life of cyanobacteria

    NARCIS (Netherlands)

    Compaoré, J.

    2010-01-01

    The results described in this thesis reveal that unicellular diazotrophic cyanobacteria are unable to fix N2 under fully aerobic conditions. This suggests that in their natural environment these organisms must be exposed to O2 concentrations well below air saturation at least during the periods that

  4. Potential of industrial biotechnology with cyanobacteria and eukaryotic microalgae

    NARCIS (Netherlands)

    Wijffels, R.H.; Kruse, O.; Hellingwerf, K.J.

    2013-01-01

    Both cyanobacteria and eukaryotic microalgae are promising organisms for sustainable production of bulk products such as food, feed, materials, chemicals and fuels. In this review we will summarize the potential and current biotechnological developments.Cyanobacteria are promising host organisms for

  5. Diversity and dynamics of potentially toxic cyanobacteria and their ...

    African Journals Online (AJOL)

    Bloom–forming freshwater cyanobacteria pose human and livestock health problems due to their ability to produce toxins and other bioactive compounds. Some non-toxic cyanobacteria accumulate as buoyant surface dwelling scums and thick mats which affect the benthic fauna by degrading aquatic habitats and giving ...

  6. Baltic cyanobacteria- A source of biologically active compounds

    Digital Repository Service at National Institute of Oceanography (India)

    Mazur-Marzec, H.; Błaszczyk, A.; Felczykowska, A.; Hohlfeld, N.; Kobos, J.; Toruńska-Sitarz, A.; PrabhaDevi; Montalva`o, S.; DeSouza, L.; Tammela, P.; Mikosik, A.; Bloch, S.; Nejman-Faleńczyk, B.; Węgrzyn, G.

    cyanobacteria, enzyme activity, enzyme inhibitors, immunological activity, natural products, nonribosomal peptides, plant growth regulators 2 INTRODUCTION Cyanobacteria are Gram-negative bacteria which are widely distributed in many water bodies..., immunological, 4 antimicrobial and plant growth tests. The overall aim of the experiments was to identify strains showing the most promising biological activity for potential biotechnological application. MATERIALS AND METHODS Isolation, culture...

  7. Human Health and Toxic Cyanobacteria – What do we know?

    Science.gov (United States)

    Human Health and Toxic Cyanobacteria – What do we know?Elizabeth D. HilbornWarm, eutrophic surface water systems support the development of toxic cyanobacteria blooms in North Carolina and worldwide. These conditions are increasing with expanding human populations and clima...

  8. Association of non-heterocystous cyanobacteria with crop plants

    NARCIS (Netherlands)

    Ahmed, M.; Stal, L.J.; Hasnain, S.

    2010-01-01

    Cyanobacteria have the ability to form associations with organisms from all domains of life, notably with plants, which they provide with fixed nitrogen, among other substances. This study was aimed at developing artificial associations between non-heterocystous cyanobacteria and selected crop

  9. Cyanobacteria species identified in the Weija and Kpong reservoirs ...

    African Journals Online (AJOL)

    The Kpong and Weija reservoirs supply drinking water to Accra, Ghana. This study was conducted to identify the cyanobacteria present in these reservoirs and to ascertain whether current treatment processes remove whole cyanobacteria cells from the drinking water produced. Cyanotoxins are mostly cell bound and could ...

  10. 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  

  11. Bio diesel production from algae

    International Nuclear Information System (INIS)

    Khola, G.; Ghazala, B.

    2011-01-01

    Algae appear to be an emerging source of biomass for bio diesel that has the potential to completely displace fossil fuel. Two thirds of earth's surface is covered with water, thus alga e would truly be renewable option of great potential for global energy needs. This study discusses specific and comparative bio diesel quantitative potential of Cladophora sp., also highlighting its biomass (after oil extraction), pH and sediments (glycerine, water and pigments) quantitative properties. Comparison of Cladophora sp., with Oedogonium sp., and Spirogyra sp., (Hossain et al., 2008) shows that Cladophora sp., produce higher quantity of bio diesel than Spirogyra sp., whereas biomass and sediments were higher than the both algal specimens in comparison to the results obtained by earlier workers. No prominent difference in pH of bio diesel was found. In Pakistan this is a first step towards bio diesel production from algae. Results indicate that Cladophora sp., provide a reasonable quantity of bio diesel, its greater biomass after oil extraction and sediments make it a better option for bio diesel production than the comparing species. (author)

  12. Fast screening and quantitation of microcystins in microalgae dietary supplement products and water by liquid chromatography coupled to time of flight mass spectrometry

    International Nuclear Information System (INIS)

    Ortelli, Didier; Edder, Patrick; Cognard, Emmanuelle; Jan, Philippe

    2008-01-01

    Cyanobacteria, commonly called 'blue-green algae', may accumulate in surface water supplies as 'blooms' and may concentrate on the surface as blue-green 'scums'. Some species of cyanobacteria produce toxins and are of relevance to water supplies and to microalgae dietary supplements. To ensure the safety of drinking water and blue-green algae products, analyses are the only way to determine the presence or absence of toxins. This paper shows the use of ultra performance liquid chromatography (UPLC) coupled to orthogonal acceleration time of flight (TOF) mass spectrometry for the detection and quantitation of microcystins. The method presented is very sensitive, simple, fast, robust and did not require fastidious clean-up step. Limits of detection of 0.1 μg L -1 in water and 0.1-0.2 μg g -1 in microalgae samples were achieved. Method performances were satisfactory and appropriate for monitoring of water and dietary supplements. The method was applied in routine to samples taken from Swiss market or buy on internet website. Among 19 samples, six showed the presence of microcystins LR and LA at harmful levels

  13. Genes, Genomes, and Assemblages of Modern Anoxygenic Photosynthetic Cyanobacteria as Proxies for Ancient Cyanobacteria

    Science.gov (United States)

    Grim, S. L.; Dick, G.

    2015-12-01

    Oxygenic photosynthetic (OP) cyanobacteria were responsible for the production of O2 during the Proterozoic. However, the extent and degree of oxygenation of the atmosphere and oceans varied for over 2 Ga after OP cyanobacteria first appeared in the geologic record. Cyanobacteria capable of anoxygenic photosynthesis (AP) may have altered the trajectory of oxygenation, yet the scope of their role in the Proterozoic is not well known. Modern cyanobacterial populations from Middle Island Sinkhole (MIS), Michigan and a handful of cultured cyanobacterial strains, are capable of OP and AP. With their metabolic versatility, these microbes may approximate ancient cyanobacterial assemblages that mediated Earth's oxygenation. To better characterize the taxonomic and genetic signatures of these modern AP/OP cyanobacteria, we sequenced 16S rRNA genes and conducted 'omics analyses on cultured strains, lab mesocosms, and MIS cyanobacterial mat samples collected over multiple years from May to September. Diversity in the MIS cyanobacterial mat is low, with one member of Oscillatoriales dominating at all times. However, Planktothrix members are more abundant in the cyanobacterial community in late summer and fall. The shift in cyanobacterial community composition may be linked to seasonally changing light intensity. In lab mesocosms of MIS microbial mat, we observed a shift in dominant cyanobacterial groups as well as the emergence of Chlorobium, bacteria that specialize in AP. These shifts in microbial community composition and metabolism are likely in response to changing environmental parameters such as the availability of light and sulfide. Further research is needed to understand the impacts of the changing photosynthetic community on oxygen production and the entire microbial consortium. Our study connects genes and genomes of AP cyanobacteria to their environment, and improves understanding of cyanobacterial metabolic strategies that may have shaped Earth's redox evolution.

  14. Cyanobacteria as a platform for biofuel production

    Directory of Open Access Journals (Sweden)

    Nicole E Nozzi

    2013-09-01

    Full Text Available Cyanobacteria have great potential as a platform for biofuel production because of their fast growth, ability to fix carbon dioxide gas, and their genetic tractability. Furthermore they do not require fermentable sugars or arable land for growth and so competition with cropland would be greatly reduced. In this perspective we discuss the challenges and areas for improvement most pertinent for advancing cyanobacterial fuel production, including: improving genetic parts, carbon fixation, metabolic flux, nutrient requirements on a large scale, and photosynthetic efficiency using natural light.

  15. Natural Product Biosynthetic Diversity and Comparative Genomics of the Cyanobacteria.

    Science.gov (United States)

    Dittmann, Elke; Gugger, Muriel; Sivonen, Kaarina; Fewer, David P

    2015-10-01

    Cyanobacteria are an ancient lineage of slow-growing photosynthetic bacteria and a prolific source of natural products with intricate chemical structures and potent biological activities. The bulk of these natural products are known from just a handful of genera. Recent efforts have elucidated the mechanisms underpinning the biosynthesis of a diverse array of natural products from cyanobacteria. Many of the biosynthetic mechanisms are unique to cyanobacteria or rarely described from other organisms. Advances in genome sequence technology have precipitated a deluge of genome sequences for cyanobacteria. This makes it possible to link known natural products to biosynthetic gene clusters but also accelerates the discovery of new natural products through genome mining. These studies demonstrate that cyanobacteria encode a huge variety of cryptic gene clusters for the production of natural products, and the known chemical diversity is likely to be just a fraction of the true biosynthetic capabilities of this fascinating and ancient group of organisms. Copyright © 2015. Published by Elsevier Ltd.

  16. Red algae and their use in papermaking.

    Science.gov (United States)

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

    2010-04-01

    Gelidialian red algae, that contain rhizoidal filaments, except the family Gelidiellaceae were processed to make bleached pulps, which can be used as raw materials for papermaking. Red algae consist of rhizoidal filaments, cortical cells usually reddish in color, and medullary cells filled with mucilaginous carbohydrates. Red algae pulp consists of mostly rhizoidal filaments. Red algae pulp of high brightness can be produced by extracting mucilaginous carbohydrates after heating the algae in an aqueous medium and subsequently treating the extracted with bleaching chemicals. In this study, we prepared paper samples from bleached pulps obtained from two red algae species (Gelidium amansii and Gelidium corneum) and compared their properties to those of bleached wood chemical pulps. Copyright 2009 Elsevier Ltd. All rights reserved.

  17. Cellulose powder from Cladophora sp. algae.

    Science.gov (United States)

    Ek, R; Gustafsson, C; Nutt, A; Iversen, T; Nyström, C

    1998-01-01

    The surface are and crystallinity was measured on a cellulose powder made from Cladophora sp. algae. The algae cellulose powder was found to have a very high surface area (63.4 m2/g, N2 gas adsorption) and build up of cellulose with a high crystallinity (approximately 100%, solid state NMR). The high surface area was confirmed by calculations from atomic force microscope imaging of microfibrils from Cladophora sp. algae.

  18. Photobioreactor cultivation strategies for microalgae and cyanobacteria.

    Science.gov (United States)

    Johnson, Tylor J; Katuwal, Sarmila; Anderson, Gary A; Gu, Liping; Zhou, Ruanbao; Gibbons, William R

    2018-03-08

    The current burden on fossil-derived chemicals and fuels combined with the rapidly increasing global population has led to a crucial need to develop renewable and sustainable sources of chemicals and biofuels. Photoautotrophic microorganisms, including cyanobacteria and microalgae, have garnered a great deal of attention for their capability to produce these chemicals from carbon dioxide, mineralized water, and solar energy. While there have been substantial amounts of research directed at scaling-up production from these microorganisms, several factors have proven difficult to overcome, including high costs associated with cultivation, photobioreactor construction, and artificial lighting. Decreasing these costs will substantially increase the economic feasibility of these production processes. Thus, the purpose of this review is to describe various photobioreactor designs, and then provide an overview on lighting systems, mixing, gas transfer, and the hydrodynamics of bubbles. These factors must be considered when the goal of a production process is economic feasibility. Targets for improving microalgae and cyanobacteria cultivation media, including water reduction strategies will also be described. As fossil fuel reserves continue to be depleted and the world population continues to increase, it is imperative that renewable chemical and biofuel production processes be developed toward becoming economically feasible. Thus, it is essential that future research is directed toward improving these processes. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 2018. © 2018 American Institute of Chemical Engineers.

  19. Biosynthesis of 3-Dimethylsulfoniopropionate in Marine Algae

    National Research Council Canada - National Science Library

    Rhodes, David

    2000-01-01

    ...) in marine algae, including identification of intermediates and enzymes of the pathway in the macroalgae Enteromorpha Intestinalis, and three diverse marine phytoplankton species; Tetraselmis sp...

  20. Algae-production in the desert

    Energy Technology Data Exchange (ETDEWEB)

    Hildebrand, H.

    1988-11-01

    The company Koor Food Ltd. (Israel) developed in co-operation with the Weizmann-Institute (Israel) a production-plant for the industrial cultivation of algae in the desert area of Elat. For almost a year now, they succeed in harvesting large amounts of algae material with the help of the intensive sun and the Red Sea water. The alga Dunaliella with the natural US -carotine, as well as the alga Spirulina with the high content of protein find their market in the food-, cosmetic- and pharma-industry. This article will give a survey of a yet here unusual project.

  1. Potential of industrial biotechnology with cyanobacteria and eukaryotic microalgae.

    Science.gov (United States)

    Wijffels, René H; Kruse, Olaf; Hellingwerf, Klaas J

    2013-06-01

    Both cyanobacteria and eukaryotic microalgae are promising organisms for sustainable production of bulk products such as food, feed, materials, chemicals and fuels. In this review we will summarize the potential and current biotechnological developments. Cyanobacteria are promising host organisms for the production of small molecules that can be secreted such as ethanol, butanol, fatty acids and other organic acids. Eukaryotic microalgae are interesting for products for which cellular storage is important such as proteins, lipids, starch and alkanes. For the development of new and promising lines of production, strains of both cyanobacteria and eukaryotic microalgae have to be improved. Transformation systems have been much better developed in cyanobacteria. However, several products would be preferably produced with eukaryotic microalgae. In the case of cyanobacteria a synthetic-systems biology approach has a great potential to exploit cyanobacteria as cell factories. For eukaryotic microalgae transformation systems need to be further developed. A promising strategy is transformation of heterologous (prokaryotic and eukaryotic) genes in established eukaryotic hosts such as Chlamydomonas reinhardtii. Experimental outdoor pilots under containment for the production of genetically modified cyanobacteria and microalgae are in progress. For full scale production risks of release of genetically modified organisms need to be assessed. Copyright © 2013. Published by Elsevier Ltd.

  2. Geographical patterns in cyanobacteria distribution: climate influence at regional scale.

    Science.gov (United States)

    Pitois, Frédéric; Thoraval, Isabelle; Baurès, Estelle; Thomas, Olivier

    2014-01-28

    Cyanobacteria are a component of public health hazards in freshwater environments because of their potential as toxin producers. Eutrophication has long been considered the main cause of cyanobacteria outbreak and proliferation, whereas many studies emphasized the effect of abiotic parameters (mainly temperature and light) on cell growth rate or toxin production. In view of the growing concerns of global change consequences on public health parameters, this study attempts to enlighten climate influence on cyanobacteria at regional scale in Brittany (NW France). The results show that homogeneous cyanobacteria groups are associated with climatic domains related to temperature, global radiation and pluviometry, whereas microcystins (MCs) occurrences are only correlated to local cyanobacteria species composition. As the regional climatic gradient amplitude is similar to the projected climate evolution on a 30-year timespan, a comparison between the present NW and SE situations was used to extrapolate the evolution of geographical cyanobacteria distribution in Brittany. Cyanobacteria composition should shift toward species associated with more frequent Microcystins occurrences along a NW/SE axis whereas lakes situated along a SW/NE axis should transition to species (mainly Nostocales) associated with lower MCs detection frequencies.

  3. Microcystin production in epiphytic cyanobacteria on submerged macrophytes.

    Science.gov (United States)

    Mohamed, Zakaria A; Al Shehri, Abdulrahman M

    2010-06-15

    Cyanotoxins have been largely studied in planktonic and benthic cyanobacteria, but microcystin (MCYST) production in epiphytic cyanobacteria has not been reported yet. The present study reports for the first time the MCYST production in epiphytic cyanobacteria on submerged macrophytes. During this study, four common submerged macrophytes in eutrophic pond in Saudi Arabia were surveyed for the presence of toxic epiphytic cyanobacteria. The results showed that chlorophyll-a and total biovolume of epiphytic cyanobacteria differed significantly among submerged plants with highest values obtained in Stratiotes aloides and lowest in Elodea canadensis. Epiphytic materials collected from Ceratophyllum demersum and S. aloides had higher species diversities than materials collected from E. canadensis and Myriophyllum verticillatum. The cyanobacteria, Merismopedia tenuissima and Leptolyngbya boryana were recorded with a high abundance in epiphytic materials collected from all submerged macrohpytes. Based on Enzyme-linked immunosorbent assay (ELISA), these two species were found to produce MCYSTs (MCYSTs) with concentrations of 1438 and 630 microg g(-1) dry weight, respectively. HPLC analysis of the methanolic extracts of the two species showed that M. tenuissima extract contained MCYST-RR and -LR/demethyl LR plus 3 minor unidentified MCYSTs, while L. boryana extract contained MCYST-YR, -LR/demethyl LR, and 2 minor unidentified MCYSTs. This study suggests that epiphytic species should be considered during monitoring of toxic cyanobacteria in water sources. 2010 Elsevier Ltd. All rights reserved.

  4. Cyanobacteria as a Source for Novel Anti-Leukemic Compounds.

    Science.gov (United States)

    Humisto, Anu; Herfindal, Lars; Jokela, Jouni; Karkman, Antti; Bjørnstad, Ronja; Choudhury, Romi R; Sivonen, Kaarina

    2016-01-01

    Cyanobacteria are an inspiring source of bioactive secondary metabolites. These bioactive agents are a diverse group of compounds which are varying in their bioactive targets, the mechanisms of action, and chemical structures. Cyanobacteria from various environments, especially marine benthic cyanobacteria, are found to be rich sources for the search for novel bioactive compounds. Several compounds with anticancer activities have been discovered from cyanobacteria and some of these have succeeded to enter the clinical trials. Varying anticancer agents are needed to overcome increasing challenges in cancer treatments. Different search methods are used to reveal anticancer compounds from natural products, but cell based methods are the most common. Cyanobacterial bioactive compounds as agents against acute myeloid leukemia are not well studied. Here we examined our new results combined with previous studies of anti-leukemic compounds from cyanobacteria with emphasis to reveal common features in strains producing such activity. We report that cyanobacteria harbor specific anti-leukemic compounds since several studied strains induced apoptosis against AML cells but were inactive against non-malignant cells like hepatocytes. We noted that particularly benthic strains from the Baltic Sea, such as Anabaena sp., were especially potential AML apoptosis inducers. Taken together, this review and re-analysis of data demonstrates the power of maintaining large culture collections for the search for novel bioactivities, and also how anti-AML activity in cyanobacteria can be revealed by relatively simple and low-cost assays.

  5. Estimating Cyanobacteria Community Dynamics and its Relationship with Environmental Factors

    Science.gov (United States)

    Luo, Wenhuai; Chen, Huirong; Lei, Anping; Lu, Jun; Hu, Zhangli

    2014-01-01

    The cyanobacteria community dynamics in two eutrophic freshwater bodies (Tiegang Reservoir and Shiyan Reservoir) was studied with both a traditional microscopic counting method and a PCR-DGGE genotyping method. Results showed that cyanobacterium Phormidium tenue was the predominant species; twenty-six cyanobacteria species were identified in water samples collected from the two reservoirs, among which fourteen were identified with the morphological method and sixteen with the PCR-DGGE method. The cyanobacteria community composition analysis showed a seasonal fluctuation from July to December. The cyanobacteria population peaked in August in both reservoirs, with cell abundances of 3.78 × 108 cells L-1 and 1.92 × 108 cells L-1 in the Tiegang and Shiyan reservoirs, respectively. Canonical Correspondence Analysis (CCA) was applied to further investigate the correlation between cyanobacteria community dynamics and environmental factors. The result indicated that the cyanobacteria community dynamics was mostly correlated with pH, temperature and total nitrogen. This study demonstrated that data obtained from PCR-DGGE combined with a traditional morphological method could reflect cyanobacteria community dynamics and its correlation with environmental factors in eutrophic freshwater bodies. PMID:24448632

  6. Ammonium photo-production by heterocytous cyanobacteria: potentials and constraints.

    Science.gov (United States)

    Grizeau, Dominique; Bui, Lan Anh; Dupré, Catherine; Legrand, Jack

    2016-08-01

    Over the last decades, production of microalgae and cyanobacteria has been developed for several applications, including novel foods, cosmetic ingredients and more recently biofuel. The sustainability of these promising developments can be hindered by some constraints, such as water and nutrient footprints. This review surveys data on N2-fixing cyanobacteria for biomass production and ways to induce and improve the excretion of ammonium within cultures under aerobic conditions. The nitrogenase complex is oxygen sensitive. Nevertheless, nitrogen fixation occurs under oxic conditions due to cyanobacteria-specific characteristics. For instance, in some cyanobacteria, the vegetative cell differentiation in heterocyts provides a well-adapted anaerobic microenvironment for nitrogenase protection. Therefore, cell cultures of oxygenic cyanobacteria have been grown in laboratory and pilot photobioreactors (Dasgupta et al., 2010; Fontes et al., 1987; Moreno et al., 2003; Nayak & Das, 2013). Biomass production under diazotrophic conditions has been shown to be controlled by environmental factors such as light intensity, temperature, aeration rate, and inorganic carbon concentration, also, more specifically, by the concentration of dissolved oxygen in the culture medium. Currently, there is little information regarding the production of extracellular ammonium by heterocytous cyanobacteria. This review compares the available data on maximum ammonium concentrations and analyses the specific rate production in cultures grown as free or immobilized filamentous cyanobacteria. Extracellular production of ammonium could be coupled, as suggested by recent research on non-diazotrophic cyanobacteria, to that of other high value metabolites. There is little information available regarding the possibility for using diazotrophic cyanobacteria as cellular factories may be in regard of the constraints due to nitrogen fixation.

  7. 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.

  8. 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

  9. 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.

  10. Microbial Profiling Of Cyanobacteria From VIT Lake

    Directory of Open Access Journals (Sweden)

    Swati Singh

    2015-08-01

    Full Text Available The application of molecular biological methods to study the diversity and ecology of micro-organisms in natural environments has been practice in mid-1980. The aim of our research is to access the diversity composition and functioning of complex microbial community found in VIT Lake. Molecular ecology is a new field in which microbes can be recognized and their function can be understood at the DNA or RNA level which is useful for constructing genetically modified microbes by recombinant DNA technology for reputed use in the environment. In this research first we will isolate cyanobacteria in lab using conventional methods like broth culture and spread plate method then we will analyze their morphology using various staining methods and DNA and protein composition using electrophoresis method. The applications of community profiling approaches will advance our understanding of the functional role of microbial diversity in VIT Lake controls on microbial community composition.

  11. 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.

  12. 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.)

  13. Composting of waste algae: a review.

    Science.gov (United States)

    Han, Wei; Clarke, William; Pratt, Steven

    2014-07-01

    Although composting has been successfully used at pilot scale to manage waste algae removed from eutrophied water environments and the compost product applied as a fertiliser, clear guidelines are not available for full scale algae composting. The review reports on the application of composting to stabilize waste algae, which to date has mainly been macro-algae, and identifies the peculiarities of algae as a composting feedstock, these being: relatively low carbon to nitrogen (C/N) ratio, which can result in nitrogen loss as NH3 and even N2O; high moisture content and low porosity, which together make aeration challenging; potentially high salinity, which can have adverse consequence for composting; and potentially have high metals and toxin content, which can affect application of the product as a fertiliser. To overcome the challenges that these peculiarities impose co-compost materials can be employed. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Co-culture of microalgae, cyanobacteria, and macromycetes for exopolysaccharides production: process preliminary optimization and partial characterization.

    Science.gov (United States)

    Angelis, S; Novak, A C; Sydney, E B; Soccol, V T; Carvalho, J C; Pandey, A; Noseda, M D; Tholozan, J L; Lorquin, J; Soccol, C R

    2012-07-01

    In this study, the biomass and exopolysaccharides (EPS) production in co-cultures of microalgae/cyanobacteria and macromycetes was evaluated as a technology for producing new polysaccharides for medical and/or industrial application. Based on biomass and EPS productivity of monocultures, two algae and two fungi were selected and cultured in different co-culture arrangements. The hydrosoluble EPS fractions from mono- and co-cultures were characterized by ¹³C NMR spectroscopy and gas chromatography coupled to mass spectrometry and compared. It was found that co-cultures resulted in the production of an EPS different from those produced by monocultures, showing fungal predominance with microalgal/cyanobacterial traces. Co-cultures conditions were screened (temperature, agitation speed, fungal and microalgae inoculation rate, initial pH, illumination rate, and glucose concentration) in order to achieve maximum biomass and EPS production, resulting in an increase of 33 and 61% in exopolysaccharides and biomass productions, respectively (patent pending).

  15. Use of HPLC for the detection of iron chelators in cultures of bacteria, fungi, and algae

    International Nuclear Information System (INIS)

    Boyer, G.L.; Speirs, R.J.; Morse, P.D.

    1990-01-01

    Iron is essential for the growth of living cells. To meet biochemical needs, microorganisms, including algae, produce high affinity chelators termed siderophores. These compounds solubilize Fe and increase its bioavailability. We have developed a new method to study siderophore formation in cultured and natural environments. Based on the fact siderophores tightly bind 55-Fe, the radioactive complexes can be separated by HPLC using an inert PRP-1 column and detected by scintillation counting. This method cleanly resolves several known siderophores, including ferrichrome A, ferrichrome, desferal, and rhodotorulic acid. The optimization of the method and its use for analysis of siderophore formation in bacteria (E. coli, and Bacillus megaterium), fungi (Ustilago sphaerogena), and cyanobacteria (Anabaena flos-aqua UTEX 1444 and Anabaena sp. ATCC 27898) will be presented

  16. Prospects of using algae in biofuel production

    Directory of Open Access Journals (Sweden)

    Y. I. Maltsev

    2017-08-01

    Full Text Available The development of industry, agriculture and the transport sector is associated with the use of various energy sources. Renewable energy sources, including biofuels, are highly promising in this respect. As shown by a number of scientific studies, a promising source for biofuel production that would meet modern requirements may be algal biomass. After activation of the third generation biodiesel production it was assumed that the algae would become the most advantageous source, because it is not only able to accumulate significant amounts of lipids, but could reduce the of agricultural land involved in biofuel production and improve air quality by sequestering CO2. However, a major problem is presented by the cost of algae biomass cultivation and its processing compared to the production of biodiesel from agricultural crops. In this regard, there are several directions of increasing the efficiency of biodiesel production from algae biomass. The first direction is to increase lipid content in algae cells by means of genetic engineering. The second direction is connected with the stimulation of increased accumulation of lipids by stressing algae. The third direction involves the search for new, promising strains of algae that will be characterized by faster biomass accumulation rate, higher content of TAG and the optimal proportions of accumulated saturated and unsaturated fatty acids compared to the already known strains. Recently, a new approach in the search for biotechnologically valuable strains of algae has been formed on the basis of predictions of capacity for sufficient accumulation of lipids by clarifying the evolutionary relationships within the major taxonomic groups of algae. The outcome of these studies is the rapid cost reduction of biofuel production based on algae biomass. All this emphasizes the priority of any research aimed at both improving the process of production of biofuels from algae, and the search for new sources for

  17. Algas marinas bentónicas de la costa noroccidental de Guerrero, México Benthic marine algae of the west coast of Guerrero, Mexico

    Directory of Open Access Journals (Sweden)

    Luz Elena Mateo-Cid

    2012-12-01

    Full Text Available Se presentan los resultados de un estudio sobre algas marinas bentónicas en 7 localidades de la costa noroccidental de Guerrero, México. Se determinó la presencia de 163 especies de algas marinas. Se identificaron 17 especies de Cyanobacteria, 93 Rhodophyta, 28 Chlorophyta y 25 de Heterokontophyta. Se citan 54 registros nuevos para el litoral de Guerrero, 2 también nuevos, Myrionema strangulans Greville y Acrochaete ramosa (N.L.Gardner O'Kelly para la costa del Pacífico. Cada especie se acompaña de datos sobre su distribución en el área de estudio, su estado reproductivo, nivel de marea, hábitat, observaciones, epifitismo y número de herbario o de recolección. Se comparó la riqueza específica entre la estación climática de lluvias y la de secas. La división Rhodophyta dominó en términos de diversidad en relación con las 3 divisiones restantes. La ficoflora de la costa noroccidental de Guerrero es de afinidad tropical y más diversa en la época de secas.We present results on the study on benthic marine algae in 7 localities from the west coast of Guerrero, Mexico. We report 163 species: 17 Cyanobacteria, 93 Rhodophyta, 28 Chlorophyta and 25 Heterokontophyta. Fifty four are new records for Guerrero; while Myrionema strangulans Greville and Acrochaete ramosa (N.L.Gardner O'Kelly are new to the Pacific coast of Mexico. Each species includes data on its distribution, reproductive stages, tidal level, facies, epiphytism and herbarium's number. Species diversity was compared for 2 different climatic seasons. The Rhodophyta are dominant in terms of diversity in relation to the other groups. The algal flora of the northwest coast of Guerrero is tropical and the greatest diversity was found during dry seasons.

  18. Metabolic engineering of cyanobacteria for the synthesis of commodity products

    NARCIS (Netherlands)

    Angermayr, S.A.; Gorchs Rovira, A.; Hellingwerf, K.J.

    2015-01-01

    Through metabolic engineering cyanobacteria can be employed in biotechnology. Combining the capacity for oxygenic photosynthesis and carbon fixation with an engineered metabolic pathway allows carbon-based product formation from CO2, light, and water directly. Such cyanobacterial 'cell factories'

  19. Cyanobacteria as photosynthetic biocatalysts: a systems biology perspective.

    Science.gov (United States)

    Gudmundsson, Steinn; Nogales, Juan

    2015-01-01

    The increasing need to replace oil-based products and to address global climate change concerns has triggered considerable interest in photosynthetic microorganisms. Cyanobacteria, in particular, have great potential as biocatalysts for fuels and fine-chemicals. During the last few years the biotechnological applications of cyanobacteria have experienced an unprecedented increase and the use of these photosynthetic organisms for chemical production is becoming a tangible reality. However, the field is still immature and many concerns about the economic feasibility of the biotechnological potential of cyanobacteria remain. In this review we describe recent successes in biofuel and fine-chemical production using cyanobacteria. We discuss the role of the photosynthetic metabolism and highlight the need for systems-level metabolic optimization in order to achieve the true potential of cyanobacterial biocatalysts.

  20. Cyanobacteria and cyanotoxins at the river-estuarine transition.

    Science.gov (United States)

    Bukaveckas, Paul A; Franklin, Rima; Tassone, Spencer; Trache, Brendan; Egerton, Todd

    2018-06-01

    We examined seasonal and longitudinal patterns in the occurrence of toxic cyanobacteria in the James River Estuary (Virginia). Highest chlorophyll and cyanobacteria levels were observed in the tidal freshwater segment, particularly during dry summers when freshwater replacement time was long. Cyanobacteria accounted for a small proportion of phytoplankton biomass (7-15%), and Microcystis comprised a small proportion of the cyanobacteria (85% of samples in July, August and September), fish tissues (87% of planktivorous fishes) and shellfish (83% of individuals). Generic indicators of algal blooms (chlorophyll and algal biomass) had limited utility for predicting microcystin concentrations. However, chlorophyll was found to be a useful predictor for the probability of exceeding specific toxin thresholds. Tissue microcystin concentrations were highest in fish and shellfish collected from the tidal fresh segment, but were detectable in biota collected from the oligohaline at distances 50 km seaward. Copyright © 2018 Elsevier B.V. All rights reserved.

  1. Nitrogen fixation by cyanobacteria stimulates production in Baltic food webs.

    Science.gov (United States)

    Karlson, Agnes M L; Duberg, Jon; Motwani, Nisha H; Hogfors, Hedvig; Klawonn, Isabell; Ploug, Helle; Barthel Svedén, Jennie; Garbaras, Andrius; Sundelin, Brita; Hajdu, Susanna; Larsson, Ulf; Elmgren, Ragnar; Gorokhova, Elena

    2015-06-01

    Filamentous, nitrogen-fixing cyanobacteria form extensive summer blooms in the Baltic Sea. Their ability to fix dissolved N2 allows cyanobacteria to circumvent the general summer nitrogen limitation, while also generating a supply of novel bioavailable nitrogen for the food web. However, the fate of the nitrogen fixed by cyanobacteria remains unresolved, as does its importance for secondary production in the Baltic Sea. Here, we synthesize recent experimental and field studies providing strong empirical evidence that cyanobacterial nitrogen is efficiently assimilated and transferred in Baltic food webs via two major pathways: directly by grazing on fresh or decaying cyanobacteria and indirectly through the uptake by other phytoplankton and microbes of bioavailable nitrogen exuded from cyanobacterial cells. This information is an essential step toward guiding nutrient management to minimize noxious blooms without overly reducing secondary production, and ultimately most probably fish production in the Baltic Sea.

  2. Cyanobacteria Occurrence and Nitrogen Fixation Rates in the ...

    African Journals Online (AJOL)

    Keywords: Cyanobacteria, Nitrogen Fixation, Seagrass, Seaweed Farming. Abstract—The .... during every sampling period, using a mercury thermometer and a ..... Capone, D.G. (1993) Determination of nitrogenase activity in aquatic samples ...

  3. Human Health Effects Associated with Exposure to Toxic Cyanobacteria

    Science.gov (United States)

    Reports of toxic cyanobacteria blooms are increasing worldwide. Warming and eutrophic surface water systems support the development of blooms. We examine the evidence for adverse human health effects associated with exposure to toxic blooms in drinking water, recreational water a...

  4. Design of magnetic akaganeite-cyanobacteria hybrid biofilms

    International Nuclear Information System (INIS)

    Dahoumane, Si Amar; Djediat, Chakib; Yepremian, Claude; Coute, Alain; Fievet, Fernand; Brayner, Roberta

    2010-01-01

    Common Anabaena cyanobacteria are shown to form intra-cellularly akaganeite β-FeOOH nanorods of well-controlled size and unusual morphology at room temperature. High-resolution transmission electron microscopy showed that these nanorods present a complex arrangement of pores forming a spongelike structure. These hybrid akaganeite-cyanobacteria were used to form 'one-pot' hybrid biofilms. The hybrid biofilm presents higher coercivity (H c = 44.6 kA m -1 (560 Oe)) when compared to lyophilized akaganeite-cyanobacteria powder (H c = 0.8 kA m -1 (10 Oe)) due to the quasi-assembly of the cells on the glass substrate compared to the lyophilized randomly akaganeite-cyanobacteria powder.

  5. Nutritional quality of two cyanobacteria : How rich is 'poor' food?

    DEFF Research Database (Denmark)

    Schmidt, K.; Jonasdottir, Sigrun

    1997-01-01

    Cyanobacteria have often been described to be nutritionally inadequate and to interfere with zooplankton feeding. In laboratory experiments we offered 2 cyanobacteria, a unicellular Microcystis aeruginosa strain and the filamentous Nodularia sprumigena, to the calanoid copepod Acartia tonsa...... as the sole diet and in food mixtures with the nutritious diatom Thalassiosira weissflogii. Egg production was used as criterion of food quality. The use of cyanobacteria alone was an insufficient diet. However, with increasing additions of M. aeruginosa and N. spumigena to the diatom, different effects were...... observed. Large additions of cyanobacteria resulted in lower egg production and often in elevated mortality of the females, but small additions of M. aeruginosa caused an increase of about 25 % in egg production compared to a pure diatom diet. The influence of similar low concentrations of N. spumigena...

  6. Cyanobactins from Cyanobacteria: Current Genetic and Chemical State of Knowledge.

    Science.gov (United States)

    Martins, Joana; Vasconcelos, Vitor

    2015-11-13

    Cyanobacteria are considered to be one of the most promising sources of new, natural products. Apart from non-ribosomal peptides and polyketides, ribosomally synthesized and post-translationally modified peptides (RiPPs) are one of the leading groups of bioactive compounds produced by cyanobacteria. Among these, cyanobactins have sparked attention due to their interesting bioactivities and for their potential to be prospective candidates in the development of drugs. It is assumed that the primary source of cyanobactins is cyanobacteria, although these compounds have also been isolated from marine animals such as ascidians, sponges and mollusks. The aim of this review is to update the current knowledge of cyanobactins, recognized as being produced by cyanobacteria, and to emphasize their genetic clusters and chemical structures as well as their bioactivities, ecological roles and biotechnological potential.

  7. Antibacterial and antifungal activities of selected microalgae and cyanobacteria

    Czech Academy of Sciences Publication Activity Database

    Najdenski, H. M.; Gigova, L. G.; Iliev, I. I.; Pilarski, P. S.; Lukavský, Jaromír; Tsvetkova, I. V.; Ninova, M. S.; Kussovski, V. K.

    2013-01-01

    Roč. 48, č. 7 (2013), s. 1533-1540 ISSN 0950-5423 Institutional support: RVO:67985939 Keywords : antimicrobial activity * cyanobacteria * microalgae Subject RIV: EF - Botanics Impact factor: 1.354, year: 2013

  8. Origin of Blue-Green Emission in α-Zn2P2O7 and Local Structure of Ln3+ Ion in α-Zn2P2O7:Ln3+ (Ln = Sm, Eu): Time-Resolved Photoluminescence, EXAFS, and DFT Measurements.

    Science.gov (United States)

    Gupta, Santosh Kumar; Ghosh, Partha Sarathi; Yadav, Ashok Kumar; Jha, Shambhu Nath; Bhattacharyya, Dibyendu; Kadam, Ramakant Mahadeo

    2017-01-03

    Considering the fact that pyrophosphate-based hosts are in high demand for making highly efficient luminescence materials, we doped two visible lanthanide ions, viz. Sm 3+ and Eu 3+ , in Zn 2 P 2 O 7 . Interestingly, it was oberved that pure Zn 2 P 2 O 7 displayed blue-green dual emission on irradiation with ultraviolet light. Emission and lifetime spectroscopy shows the presence of defects in pyrophosphate samples which are responsible for such emission. DFT calculations clearly pinpointed that the electronic transitions between defect states located at just below the conduction band minimum (arises due to V O 1+ and V O 2+ defects) and valence band maximum, as well as impurity states situated in the band gap, can lead to dual emission in the blue-green region, as is also indicated by emission and lifetime spectra. X-ray absorption near edge spectroscopy (XANES) shows the stabilization of europium as well as samarium ion in the +3 oxidation state in α-Zn 2 P 2 O 7 . The fact that α-Zn 2 P 2 O 7 has two different coordination numbers for zinc ions, i.e. five- and six-coordinate, the study of dopant ion distribution in this particular matrix will be an important step in realizing a highly efficient europium- and samarium-based red-emitting phosphor. Time resolved photoluminescence (TRPL) shows that both of these ions are heterogeneously distributed between five- and six-coordinated Zn 2+ sites and it is the six-coordinated Zn 2+ site which is the most favorable for lanthanide ion doping. Extended X-ray absorption fine structure (EXAFS) measurements also suggested that a six-coordinated zinc ion is the preferred site occupied by trivalent lanthanide ions, which is in complete agreement with TRPL results. It was observed that there is almost complete transfer of photon energy from Zn 2 P 2 O 7 to Eu 3+ , whereas this transfer is inefficient and almost incomplete in case of Sm 3+ , which is indeed important information for the realization of pyrophosphate

  9. CyanoBase: the cyanobacteria genome database update 2010.

    Science.gov (United States)

    Nakao, Mitsuteru; Okamoto, Shinobu; Kohara, Mitsuyo; Fujishiro, Tsunakazu; Fujisawa, Takatomo; Sato, Shusei; Tabata, Satoshi; Kaneko, Takakazu; Nakamura, Yasukazu

    2010-01-01

    CyanoBase (http://genome.kazusa.or.jp/cyanobase) is the genome database for cyanobacteria, which are model organisms for photosynthesis. The database houses cyanobacteria species information, complete genome sequences, genome-scale experiment data, gene information, gene annotations and mutant information. In this version, we updated these datasets and improved the navigation and the visual display of the data views. In addition, a web service API now enables users to retrieve the data in various formats with other tools, seamlessly.

  10. CyanoBase: the cyanobacteria genome database update 2010

    OpenAIRE

    Nakao, Mitsuteru; Okamoto, Shinobu; Kohara, Mitsuyo; Fujishiro, Tsunakazu; Fujisawa, Takatomo; Sato, Shusei; Tabata, Satoshi; Kaneko, Takakazu; Nakamura, Yasukazu

    2009-01-01

    CyanoBase (http://genome.kazusa.or.jp/cyanobase) is the genome database for cyanobacteria, which are model organisms for photosynthesis. The database houses cyanobacteria species information, complete genome sequences, genome-scale experiment data, gene information, gene annotations and mutant information. In this version, we updated these datasets and improved the navigation and the visual display of the data views. In addition, a web service API now enables users to retrieve the data in var...

  11. Combined effects of toxic cyanobacteria Microcystis aeruginosa and hypoxia on the physiological responses of triangle sail mussel Hyriopsis cumingii.

    Science.gov (United States)

    Hu, Menghong; Wu, Fangli; Yuan, Mingzhe; Liu, Qigen; Wang, Youji

    2016-04-05

    The single and combined effects of toxic cyanobacteria Microcystis aeruginosa and hypoxia on the energy budget of triangle sail mussel Hyriopsis cumingii were determined in terms of scope for growth (SfG). Mussels were exposed to different combinations of toxic M. aeruginosa (0%, 50%, and 100% of total dietary dry weight) and dissolved oxygen concentrations (1, 3, and 6.0mg O2l(-1)) with a 3×3 factorial design for 14 days, followed by a recovery period with normal conditions for 7 days. Microcystin contents in mussel tissues increased with the increase in the exposed M. aeruginosa concentration at each sampling time. Adverse physiological responses of H. cumingii under toxic M. aeruginosa and hypoxic exposure were found in terms of clearance rate, absorption efficiency, respiration rate, excretion rate, and SfG. Results emphasized the importance of combined effects of hypoxia and toxic cyanobacteria on H. cumingii bioenergetic parameters, highlighted the interactive effects of toxic algae and hypoxia, and implied that the two stressors affected H. cumingii during the exposure period and showed carryover effects later. Thus, if H. cumingii is used as a bioremediation tool to eliminate M. aeruginosa, the waters should be oxygenated. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. The biological soil crusts of the San Nicolas Island: Enigmatic algae from a geographically isolated ecosystem

    Science.gov (United States)

    Flechtner, V.R.; Johansen, J.R.; Belnap, J.

    2008-01-01

    Composite soil samples from 7 sites on San Nicolas Island were evaluated quantitatively and qualitatively for the presence of cyanobacteria and eukaryotic microalgae. Combined data demonstrated a rich algal flora with 19 cyanobacterial and 19 eukaryotic microalgal genera being identified, for a total of 56 species. Nine new species were identified and described among the cyanobacteria and the eukaryotic microalgae that were isolated: Leibleinia edaphica, Aphanothece maritima, Chroococcidiopsis edaphica, Cyanosarcina atroveneta, Hassallia californica, Hassallia pseudoramosissima, Microchaete terrestre, Palmellopsis californiens, and Pseudotetracystis compactis. Distinct distributional patterns of algal taxa existed among sites on the island and among soil algal floras of western North America. Some algal taxa appeared to be widely distributed across many desert regions, including Microcoleus vaginatus, Nostoc punctiforme, Nostoc paludosum, and Tolypothrix distorta, Chlorella vulgaris, Diplosphaera cf. chodatii, Myrmecia astigmatica, Myrmecia biatorellae, Hantzschia amphioxys, and Luticola mutica. Some taxa share a distinctly southern distribution with soil algae from southern Arizona, southern California, and Baja California (e.g., Scenedesmus deserticola and Eustigmatos magnus). The data presented herein support the view that the cyanobacterial and microalgal floras of soil crusts possess significant biodiversity, much of it previously undescribed.

  13. 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

  14. 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.

  15. Prokaryotic algae associated with Australian proterozoic stromatolites.

    Science.gov (United States)

    Licari, G R; Cloud, P

    1972-09-01

    Five instances of association between distinctive stromatolites and blue-green algal nannofossils are recorded from a 100-m sequence of carbonate rocks about 1.6 x 10(9) years old, along the south side of Paradise Creek, northwestern Queensland, Australia. No eukaryotes were identified in any of these systematically limited assemblages, although they are known from rocks as old as 1.3 x 10(9) years in eastern California. Thus, eukaryotes may not have appeared until after 1.6 x 10(9) years ago (but before 1.3 x 10(9) years ago). The associations observed would also be consistent with (but do not prove) a biotic influence on stromatolite morphology. As is usual among prePaleozoic forms described, the morphology of the nannofossils is very similar to living forms, displaying marked evolutionary conservatism. Primary orientation of stromatolitic laminae and columns is not invariably convex upward, as conventionally believed, but convex away from and parallel to the initial point or surface of attachment, which may be horizontal or even downward beneath overhangs.

  16. 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.

  17. Microbial community structures in high rate algae ponds for bioconversion of agricultural wastes from livestock industry for feed production.

    Science.gov (United States)

    Mark Ibekwe, A; Murinda, Shelton E; Murry, Marcia A; Schwartz, Gregory; Lundquist, Trygve

    2017-02-15

    Dynamics of seasonal microbial community compositions in algae cultivation ponds are complex. However, there is very limited knowledge on bacterial communities that may play significant roles with algae in the bioconversion of manure nutrients to animal feed. In this study, water samples were collected during winter, spring, summer, and fall from the dairy lagoon effluent (DLE), high rate algae ponds (HRAP) that were fed with diluted DLE, and municipal waste water treatment plant (WWTP) effluent which was included as a comparison system for the analysis of total bacteria, Cyanobacteria, and microalgae communities using MiSeq Illumina sequencing targeting the 16S V4 rDNA region. The main objective was to examine dynamics in microbial community composition in the HRAP used for the production of algal biomass. DNA was extracted from the different sample types using three commercially available DNA extraction kits; MoBio Power water extraction kit, Zymo fungi/bacterial extraction kit, and MP Biomedicals FastDNA SPIN Kit. Permutational analysis of variance (PERMANOVA) using distance matrices on each variable showed significant differences (P=0.001) in beta-diversity based on sample source. Environmental variables such as hydraulic retention time (HRT; P<0.031), total N (P<0.002), total inorganic N (P<0.002), total P (P<0.002), alkalinity (P<0.002), pH (P<0.022), total suspended solid (TSS; P<0.003), and volatile suspended solids (VSS; P<0.002) significantly affected microbial communities in DLE, HRAP, and WWTP. Of the operational taxonomic units (OTUs) identified to phyla level, the dominant classes of bacteria identified were: Cyanobacteria, Alpha-, Beta-, Gamma-, Epsilon-, and Delta-proteobacteria, Bacteroidetes, Firmicutes, and Planctomycetes. Our data suggest that microbial communities were significantly affected in HRAP by different environmental variables, and care must be taken in extraction procedures when evaluating specific groups of microbial communities for

  18. 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...

  19. Algae, phytoplankton and eutrophication research and management ...

    African Journals Online (AJOL)

    The role of algal and phytoplankton research and the focus shift to cyanobacteria, because of eutrophication in South African aquatic systems, are highlighted, which indicates the different modelling and management methods that have been used and tested. Recommendations are made for future research. Keywords: ...

  20. Nitrogen fixed by cyanobacteria is utilized by deposit-feeders.

    Science.gov (United States)

    Karlson, Agnes M L; Gorokhova, Elena; Elmgren, Ragnar

    2014-01-01

    Benthic communities below the photic zone depend for food on allochthonous organic matter derived from seasonal phytoplankton blooms. In the Baltic Sea, the spring diatom bloom is considered the most important input of organic matter, whereas the contribution of the summer bloom dominated by diazotrophic cyanobacteria is less understood. The possible increase in cyanobacteria blooms as a consequence of eutrophication and climate change calls for evaluation of cyanobacteria effects on benthic community functioning and productivity. Here, we examine utilization of cyanobacterial nitrogen by deposit-feeding benthic macrofauna following a cyanobacteria bloom at three stations during two consecutive years and link these changes to isotopic niche and variations in body condition (assayed as C:N ratio) of the animals. Since nitrogen-fixing cyanobacteria have δ(15)N close to -2‰, we expected the δ(15)N in the deposit-feeders to decrease after the bloom if their assimilation of cyanobacteria-derived nitrogen was substantial. We also expected the settled cyanobacteria with their associated microheterotrophic community and relatively high nitrogen content to increase the isotopic niche area, trophic diversity and dietary divergence between individuals (estimated as the nearest neighbour distance) in the benthic fauna after the bloom. The three surface-feeding species (Monoporeia affinis, Macoma balthica and Marenzelleria arctia) showed significantly lower δ(15)N values after the bloom, while the sub-surface feeder Pontoporeia femorata did not. The effect of the bloom on isotopic niche varied greatly between stations; populations which increased niche area after the bloom had better body condition than populations with reduced niche, regardless of species. Thus, cyanobacterial nitrogen is efficiently integrated into the benthic food webs in the Baltic, with likely consequences for their functioning, secondary production, transfer efficiency, trophic interactions, and

  1. Nitrogen fixed by cyanobacteria is utilized by deposit-feeders.

    Directory of Open Access Journals (Sweden)

    Agnes M L Karlson

    Full Text Available Benthic communities below the photic zone depend for food on allochthonous organic matter derived from seasonal phytoplankton blooms. In the Baltic Sea, the spring diatom bloom is considered the most important input of organic matter, whereas the contribution of the summer bloom dominated by diazotrophic cyanobacteria is less understood. The possible increase in cyanobacteria blooms as a consequence of eutrophication and climate change calls for evaluation of cyanobacteria effects on benthic community functioning and productivity. Here, we examine utilization of cyanobacterial nitrogen by deposit-feeding benthic macrofauna following a cyanobacteria bloom at three stations during two consecutive years and link these changes to isotopic niche and variations in body condition (assayed as C:N ratio of the animals. Since nitrogen-fixing cyanobacteria have δ(15N close to -2‰, we expected the δ(15N in the deposit-feeders to decrease after the bloom if their assimilation of cyanobacteria-derived nitrogen was substantial. We also expected the settled cyanobacteria with their associated microheterotrophic community and relatively high nitrogen content to increase the isotopic niche area, trophic diversity and dietary divergence between individuals (estimated as the nearest neighbour distance in the benthic fauna after the bloom. The three surface-feeding species (Monoporeia affinis, Macoma balthica and Marenzelleria arctia showed significantly lower δ(15N values after the bloom, while the sub-surface feeder Pontoporeia femorata did not. The effect of the bloom on isotopic niche varied greatly between stations; populations which increased niche area after the bloom had better body condition than populations with reduced niche, regardless of species. Thus, cyanobacterial nitrogen is efficiently integrated into the benthic food webs in the Baltic, with likely consequences for their functioning, secondary production, transfer efficiency, trophic

  2. Stress Sensors and Signal Transducers in Cyanobacteria

    Science.gov (United States)

    Los, Dmitry A.; Zorina, Anna; Sinetova, Maria; Kryazhov, Sergey; Mironov, Kirill; Zinchenko, Vladislav V.

    2010-01-01

    In living cells, the perception of environmental stress and the subsequent transduction of stress signals are primary events in the acclimation to changes in the environment. Some molecular sensors and transducers of environmental stress cannot be identified by traditional and conventional methods. Based on genomic information, a systematic approach has been applied to the solution of this problem in cyanobacteria, involving mutagenesis of potential sensors and signal transducers in combination with DNA microarray analyses for the genome-wide expression of genes. Forty-five genes for the histidine kinases (Hiks), 12 genes for serine-threonine protein kinases (Spks), 42 genes for response regulators (Rres), seven genes for RNA polymerase sigma factors, and nearly 70 genes for transcription factors have been successfully inactivated by targeted mutagenesis in the unicellular cyanobacterium Synechocystis sp. PCC 6803. Screening of mutant libraries by genome-wide DNA microarray analysis under various stress and non-stress conditions has allowed identification of proteins that perceive and transduce signals of environmental stress. Here we summarize recent progress in the identification of sensory and regulatory systems, including Hiks, Rres, Spks, sigma factors, transcription factors, and the role of genomic DNA supercoiling in the regulation of the responses of cyanobacterial cells to various types of stress. PMID:22294932

  3. A novel potassium channel in photosynthetic cyanobacteria.

    Directory of Open Access Journals (Sweden)

    Manuela Zanetti

    Full Text Available Elucidation of the structure-function relationship of a small number of prokaryotic ion channels characterized so far greatly contributed to our knowledge on basic mechanisms of ion conduction. We identified a new potassium channel (SynK in the genome of the cyanobacterium Synechocystis sp. PCC6803, a photosynthetic model organism. SynK, when expressed in a K(+-uptake-system deficient E. coli strain, was able to recover growth of these organisms. The protein functions as a potassium selective ion channel when expressed in Chinese hamster ovary cells. The location of SynK in cyanobacteria in both thylakoid and plasmamembranes was revealed by immunogold electron microscopy and Western blotting of isolated membrane fractions. SynK seems to be conserved during evolution, giving rise to a TPK (two-pore K(+ channel family member which is shown here to be located in the thylakoid membrane of Arabidopsis. Our work characterizes a novel cyanobacterial potassium channel and indicates the molecular nature of the first higher plant thylakoid cation channel, opening the way to functional studies.

  4. Diatom algae of the Guni river (Pamir)

    International Nuclear Information System (INIS)

    Kurbonova, P.A.; Hisoriev, H.H.

    2006-01-01

    There are presented the dates of the results of diatom algae (Bacillariophyta) of the Gunt river. There was found 107 species and 9 subspecies which belong to 3 classics, 12 ordos, 13 families and 28 genus

  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.Y.

    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. Algas marinas bentónicas de la Isla Gorgona, costa pacífica colombiana

    Directory of Open Access Journals (Sweden)

    Mónica Murillo Muñoz

    2014-02-01

    Full Text Available Se presenta el listado de las algas marinas bénticas del Parque Nacional Natural Isla Gorgona, el inventario corresponde a la flora algal asociada a los diferentes ambientes marinos de la isla, a saber: arrecifes coralinos y fondos blandos. El monitoreo de las comunidades de algas se llevó a cabo entre octubre de 2010 y mayo de 2011, se realizó una estimación de abundancia y cobertura para lo cual se establecieron transeptos paralelos a la línea de costa y se evaluó el porcentaje de cobertura en cuadrantes de 0.25m². Se reportó un total de 43 especies para los dos ambientes estudiados (coralino y fondos blandos, 24 Rhodophyta, 12 Clorophyta, 6 Ochrophyta y una Cyanobacteria. El grupo más representativo fue el perteneciente a la clase Rhodophyceae, que correspondió al 55.8% de la flora inventariada. Los resultados de nuevos registros en la isla ratifican su importancia fitogeográfica, por cuanto la composición florística insular contribuye significativamente a la biodiversidad de la costa pacífica colombiana, destacándose la presencia de arrecifes coralinos como los principales ambientes marinos para el desarrollo de la flora algal de la región.

  8. The rise of algae in Cryogenian oceans and the emergence of animals.

    Science.gov (United States)

    Brocks, Jochen J; Jarrett, Amber J M; Sirantoine, Eva; Hallmann, Christian; Hoshino, Yosuke; Liyanage, Tharika

    2017-08-31

    The transition from dominant bacterial to eukaryotic marine primary productivity was one of the most profound ecological revolutions in the Earth's history, reorganizing the distribution of carbon and nutrients in the water column and increasing energy flow to higher trophic levels. But the causes and geological timing of this transition, as well as possible links with rising atmospheric oxygen levels and the evolution of animals, remain obscure. Here we present a molecular fossil record of eukaryotic steroids demonstrating that bacteria were the only notable primary producers in the oceans before the Cryogenian period (720-635 million years ago). Increasing steroid diversity and abundance marks the rapid rise of marine planktonic algae (Archaeplastida) in the narrow time interval between the Sturtian and Marinoan 'snowball Earth' glaciations, 659-645 million years ago. We propose that the incumbency of cyanobacteria was broken by a surge of nutrients supplied by the Sturtian deglaciation. The 'Rise of Algae' created food webs with more efficient nutrient and energy transfers, driving ecosystems towards larger and increasingly complex organisms. This effect is recorded by the concomitant appearance of biomarkers for sponges and predatory rhizarians, and the subsequent radiation of eumetazoans in the Ediacaran period.

  9. Alternative photosynthetic electron transport pathways during anaerobiosis in the green alga Chlamydomonas reinhardtii.

    Science.gov (United States)

    Hemschemeier, Anja; Happe, Thomas

    2011-08-01

    Oxygenic photosynthesis uses light as energy source to generate an oxidant powerful enough to oxidize water into oxygen, electrons and protons. Upon linear electron transport, electrons extracted from water are used to reduce NADP(+) to NADPH. The oxygen molecule has been integrated into the cellular metabolism, both as the most efficient electron acceptor during respiratory electron transport and as oxidant and/or "substrate" in a number of biosynthetic pathways. Though photosynthesis of higher plants, algae and cyanobacteria produces oxygen, there are conditions under which this type of photosynthesis operates under hypoxic or anaerobic conditions. In the unicellular green alga Chlamydomonas reinhardtii, this condition is induced by sulfur deficiency, and it results in the production of molecular hydrogen. Research on this biotechnologically relevant phenomenon has contributed largely to new insights into additional pathways of photosynthetic electron transport, which extend the former concept of linear electron flow by far. This review summarizes the recent knowledge about various electron sources and sinks of oxygenic photosynthesis besides water and NADP(+) in the context of their contribution to hydrogen photoproduction by C. reinhardtii. This article is part of a Special Issue entitled: Regulation of Electron Transport in Chloroplasts. Copyright © 2011 Elsevier B.V. All rights reserved.

  10. Tracking polycyclic aromatic hydrocarbons in lichens: It's all about the algae

    International Nuclear Information System (INIS)

    Augusto, Sofia; Sierra, Jordi; Nadal, Martí; Schuhmacher, Marta

    2015-01-01

    Lichens, symbioses of fungi and algae and/or cyanobacteria, have the remarkable ability to uptake and accumulate semivolatile organic compounds (SVOC) from air, including polycyclic aromatic hydrocarbons (PAHs), but the mechanism of accumulation is still unknown. Understanding these mechanisms is critical to standardize the use of lichens as environmental bioindicators and to further integrate them in air monitoring networks. Through a series of experiments we show that gas phase PAHs easily cross lichen's surface and accumulate in the photosynthetic algal layer of lichens. Once accumulated, they remain in the algal layer and not within the fungus hyphae, or adhered to lichen's surface, as it was previously supposed to happen. Additionally, when lichens are washed, gas phase PAHs still remain in the algal layer. Our results reveal that lichens may be utilized as bioindicators of gas phase PAHs, overcoming current limitations of air monitoring. - Highlights: • Gas phase PAHs accumulate in the photosynthetic algal layer of lichens. • When lichens are washed by rain, gas phase PAHs remain in the algal layer. • Algae content may be a source of variability when interpreting PAH data in lichens. - Gas phase PAHs easily cross lichen's surface and accumulate in the photosynthetic algal layer of lichens.

  11. Evaluation of extracellular products and mutagenicity in cyanobacteria cultures separated from a eutrophic reservoir

    International Nuclear Information System (INIS)

    Huang, W.-J.; Lai, C.-H.; Cheng, Y.-L.

    2007-01-01

    The algal extracellular products (ECPs) in three cultures of cyanobacteria species (Anabaena, Microcystis, and Oscillatoria) dominating the eutrophic reservoir populations and their toxins have been investigated in the present work. Using gas chromatography coupled with high-resolution electron-impact mass spectrometry (GC/EI-MS) and high performance anion-exchange chromatography (HPAEC) techniques, more than 20 compounds were found in the algal culture (including cells and filtrates) extracts. The main identified ECPs were classified to polysaccharides, hydrocarbons, and aldehydes. Odor causing substances such as trans-1,10-dimethyl-trans-9-decalol (geosmin) and 2-methylisoborneol (2-MIB)were also found in the algal cultures. The potential mutagenicity of the algal suspensions was also studied with the Ames test. The organic extracts of the algal suspension from the axenic cultures were mutagenicity in TA98 without S9 mix and in TA100 with and without S9 mix. The results indicate that the ECPs of three algae species dominating the eutrophic reservoir were mutagenic clearly in the bacterial test

  12. Sustainable Algae Biodiesel Production in Cold Climates

    OpenAIRE

    Baliga, Rudras; Powers, Susan E.

    2010-01-01

    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 ...

  13. 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.

  14. Signature proteins for the major clades of Cyanobacteria

    Directory of Open Access Journals (Sweden)

    Mathews Divya W

    2010-01-01

    Full Text Available Abstract Background The phylogeny and taxonomy of cyanobacteria is currently poorly understood due to paucity of reliable markers for identification and circumscription of its major clades. Results A combination of phylogenomic and protein signature based approaches was used to characterize the major clades of cyanobacteria. Phylogenetic trees were constructed for 44 cyanobacteria based on 44 conserved proteins. In parallel, Blastp searches were carried out on each ORF in the genomes of Synechococcus WH8102, Synechocystis PCC6803, Nostoc PCC7120, Synechococcus JA-3-3Ab, Prochlorococcus MIT9215 and Prochlor. marinus subsp. marinus CCMP1375 to identify proteins that are specific for various main clades of cyanobacteria. These studies have identified 39 proteins that are specific for all (or most cyanobacteria and large numbers of proteins for other cyanobacterial clades. The identified signature proteins include: (i 14 proteins for a deep branching clade (Clade A of Gloebacter violaceus and two diazotrophic Synechococcus strains (JA-3-3Ab and JA2-3-B'a; (ii 5 proteins that are present in all other cyanobacteria except those from Clade A; (iii 60 proteins that are specific for a clade (Clade C consisting of various marine unicellular cyanobacteria (viz. Synechococcus and Prochlorococcus; (iv 14 and 19 signature proteins that are specific for the Clade C Synechococcus and Prochlorococcus strains, respectively; (v 67 proteins that are specific for the Low B/A ecotype Prochlorococcus strains, containing lower ratio of chl b/a2 and adapted to growth at high light intensities; (vi 65 and 8 proteins that are specific for the Nostocales and Chroococcales orders, respectively; and (vii 22 and 9 proteins that are uniquely shared by various Nostocales and Oscillatoriales orders, or by these two orders and the Chroococcales, respectively. We also describe 3 conserved indels in flavoprotein, heme oxygenase and protochlorophyllide oxidoreductase proteins that

  15. Genome fluctuations in cyanobacteria reflect evolutionary, developmental and adaptive traits

    Directory of Open Access Journals (Sweden)

    Nylander Johan AA

    2011-06-01

    Full Text Available Abstract Background Cyanobacteria belong to an ancient group of photosynthetic prokaryotes with pronounced variations in their cellular differentiation strategies, physiological capacities and choice of habitat. Sequencing efforts have shown that genomes within this phylum are equally diverse in terms of size and protein-coding capacity. To increase our understanding of genomic changes in the lineage, the genomes of 58 contemporary cyanobacteria were analysed for shared and unique orthologs. Results A total of 404 protein families, present in all cyanobacterial genomes, were identified. Two of these are unique to the phylum, corresponding to an AbrB family transcriptional regulator and a gene that escapes functional annotation although its genomic neighbourhood is conserved among the organisms examined. The evolution of cyanobacterial genome sizes involves a mix of gains and losses in the clade encompassing complex cyanobacteria, while a single event of reduction is evident in a clade dominated by unicellular cyanobacteria. Genome sizes and gene family copy numbers evolve at a higher rate in the former clade, and multi-copy genes were predominant in large genomes. Orthologs unique to cyanobacteria exhibiting specific characteristics, such as filament formation, heterocyst differentiation, diazotrophy and symbiotic competence, were also identified. An ancestral character reconstruction suggests that the most recent common ancestor of cyanobacteria had a genome size of approx. 4.5 Mbp and 1678 to 3291 protein-coding genes, 4%-6% of which are unique to cyanobacteria today. Conclusions The different rates of genome-size evolution and multi-copy gene abundance suggest two routes of genome development in the history of cyanobacteria. The expansion strategy is driven by gene-family enlargment and generates a broad adaptive potential; while the genome streamlining strategy imposes adaptations to highly specific niches, also reflected in their different

  16. Genome fluctuations in cyanobacteria reflect evolutionary, developmental and adaptive traits

    Science.gov (United States)

    2011-01-01

    Background Cyanobacteria belong to an ancient group of photosynthetic prokaryotes with pronounced variations in their cellular differentiation strategies, physiological capacities and choice of habitat. Sequencing efforts have shown that genomes within this phylum are equally diverse in terms of size and protein-coding capacity. To increase our understanding of genomic changes in the lineage, the genomes of 58 contemporary cyanobacteria were analysed for shared and unique orthologs. Results A total of 404 protein families, present in all cyanobacterial genomes, were identified. Two of these are unique to the phylum, corresponding to an AbrB family transcriptional regulator and a gene that escapes functional annotation although its genomic neighbourhood is conserved among the organisms examined. The evolution of cyanobacterial genome sizes involves a mix of gains and losses in the clade encompassing complex cyanobacteria, while a single event of reduction is evident in a clade dominated by unicellular cyanobacteria. Genome sizes and gene family copy numbers evolve at a higher rate in the former clade, and multi-copy genes were predominant in large genomes. Orthologs unique to cyanobacteria exhibiting specific characteristics, such as filament formation, heterocyst differentiation, diazotrophy and symbiotic competence, were also identified. An ancestral character reconstruction suggests that the most recent common ancestor of cyanobacteria had a genome size of approx. 4.5 Mbp and 1678 to 3291 protein-coding genes, 4%-6% of which are unique to cyanobacteria today. Conclusions The different rates of genome-size evolution and multi-copy gene abundance suggest two routes of genome development in the history of cyanobacteria. The expansion strategy is driven by gene-family enlargment and generates a broad adaptive potential; while the genome streamlining strategy imposes adaptations to highly specific niches, also reflected in their different functional capacities. A few

  17. Determination of Oxygen Production by Cyanobacteria in Desert Environment Soil

    Science.gov (United States)

    Bueno Prieto, J. E.

    2009-12-01

    The cyanobacteria have been characterized for being precursor in the production of oxygen. By means of photosynthetic reactions, they provide oxygen to the environment that surrounds them and they capture part of surrounding dioxide of carbon. This way it happened since the primitive Earth until today. Besides, these microorganisms can support the harmful effects of ultraviolet radiation. The presence of cyanobacterias in an environment like a dry tropical bioma, such as the geographical location called Desert of The Tatacoa (Huila - Colombia), is determinant to establish parameters in the search of biological origin of atmospheric oxygen detected in Mars. In that case, I work with a random sample of not rhizospheric soil, taken to 15 cm of depth. After determining the presence of cyanobacterias in the sample, this one was in laboratory to stimulate the oxygen production. The presence of oxygen in Mars is very interesting. Since oxygen gas is very reactive, it disappear if it is not renewed; the possibility that this renovation of oxygen has a biological origin is encouraging, bearing in mind that in a dry environment and high radiation such as the studied one, the production of oxygen by cyanobacterias is notable. Also it is necessary to keep in mind that the existence of cyanobacterias would determine water presence in Mars subsoil and the nutrients cycles renovation. An interesting exploration possibility for some future space probe to Mars might be the study of worldwide distribution of oxygen concentration in this planet and this way, indentify zones suitable for microbian life.

  18. Human health effects associated with exposure to toxic Cyanobacteria – what is the evidence?

    Science.gov (United States)

    Reports of toxic cyanobacteria blooms are increasing worldwide, as warming water and eutrophic surface water systems support the development of blooms. As awareness of toxic cyanobacteria blooms increases, reports of associated human and animal illnesses have also increased, but ...

  19. Oxygen and the light-dark cycle of nitrogenase activity in two unicellular cyanobacteria

    NARCIS (Netherlands)

    Compaore, J.; Stal, L.J.

    2010-01-01

    Cyanobacteria capable of fixing dinitrogen exhibit various strategies to protect nitrogenase from inactivation by oxygen. The marine Crocosphaera watsonii WH8501 and the terrestrial Gloeothece sp. PCC6909 are unicellular diazotrophic cyanobacteria that are capable of aerobic nitrogen fixation. These

  20. Expanding models of lake trophic state to predict cyanobacteria in lakes

    Science.gov (United States)

    Background/Question/Methods: Cyanobacteria are a primary taxonomic group associated with harmful algal blooms in lakes. Understanding the drivers of cyanobacteria presence has important implications for lake management and for the protection of human and ecosystem health. Chlor...

  1. Do photobionts influence the ecology of lichens? A case study of environmental preferences in symbiotic green alga Asterochloris (Trebouxiophyceae).

    Science.gov (United States)

    Peksa, Ondřej; Skaloud, Pavel

    2011-09-01

    The distribution patterns of symbiotic algae are thought to be conferred mainly by their hosts, however, they may originate in algal environmental requirements as well. In lichens, predominantly terrestrial associations of fungi with algae or cyanobacteria, the ecological preferences of photobionts have not been directly studied so far. Here, we examine the putative environmental requirements in lichenized alga Asterochloris, and search for the existence of ecological guilds in Asterochloris-associating lichens. Therefore, the presence of phylogenetic signal in several environmental traits was tested. Phylogenetic analysis based on the concatenated set of internal transcribed spacer rDNA and actin type I intron sequences from photobionts associated with lichens of the genera Lepraria and Stereocaulon (Stereocaulaceae, Ascomycota) revealed 13 moderately to well-resolved clades. Photobionts from particular algal clades were found to be associated with taxonomically different, but ecologically similar lichens. The rain and sun exposure were the most significant environmental factor, clearly distinguishing the Asterochloris lineages. The photobionts from ombrophobic and ombrophilic lichens were clustered in completely distinct clades. Moreover, two photobiont taxa were obviously differentiated based on their substrate and climatic preferences. Our study, thus reveals that the photobiont, generally the subsidiary member of the symbiotic lichen association, could exhibit clear preferences for environmental factors. These algal preferences may limit the ecological niches available to lichens and lead to the existence of specific lichen guilds. © 2011 Blackwell Publishing Ltd.

  2. Abscisic Acid Participates in the Control of Cell Cycle Initiation Through Heme Homeostasis in the Unicellular Red Alga Cyanidioschyzon merolae.

    Science.gov (United States)

    Kobayashi, Yuki; Ando, Hiroyuki; Hanaoka, Mitsumasa; Tanaka, Kan

    2016-05-01

    ABA is a phytohormone that is synthesized in response to abiotic stresses and other environmental changes, inducing various physiological responses. While ABA has been found in unicellular photosynthetic organisms, such as cyanobacteria and eukaryotic algae, its function in these organisms is poorly understood. Here, we found that ABA accumulated in the unicellular red alga Cyanidioschyzon merolae under conditions of salt stress and that the cell cycle G1/S transition was inhibited when ABA was added to the culture medium. A gene encoding heme-scavenging tryptophan-rich sensory protein-related protein (CmTSPO; CMS231C) was positively regulated by ABA, as in Arabidopsis, and CmTSPO bound heme in vitro. The intracellular content of total heme was increased by addition of ABA, but unfettered heme decreased, presumably due to scavenging by CmTSPO. The inhibition of DNA replication by ABA was negated by addition of heme to the culture medium. Thus, we propose a regulatory role for ABA and heme in algal cell cycle initiation. Finally, we found that a C. merolae mutant that is defective in ABA production was more susceptible to salt stress, indicating the importance of ABA to stress resistance in red algae. © The Author 2016. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  3. Total cylindrospermopsins, microcystins/nodularins, and saxitoxins data for the 2007 United States Environmental Protection Agency National Lake Assessment

    Science.gov (United States)

    Loftin, Keith A.; Dietze, Julie E.; Meyer, Michael T.; Graham, Jennifer L.; Maksimowicz, Megan M.; Toyne, Kathryn D.

    2016-05-26

    Phytoplankton communities in freshwater lakes, ponds, and reservoirs may be dominated by cyanobacteria (also called blue-green algae) under certain environmental conditions. Cyanobacteria may cause a range of water-quality impairments, including the potential for toxin production. Cyanobacteria toxins (cyanotoxins) may adversely impact human and ecological health. Microcystins are considered to be one of the most commonly found classes of cyanotoxins in freshwater ecosystems, and as such were selected as a recreational indicator of water quality for the 2007 United States Environmental Protection Agency (EPA) National Lakes Assessment. However, much less is known about the occurrence of other classes of cyanotoxins in fresh surface water such as anatoxins, cylindrospermopsins, nodularins, and saxitoxins.

  4. Phylogeny of culturable cyanobacteria from Brazilian mangroves.

    Science.gov (United States)

    Silva, Caroline Souza Pamplona; Genuário, Diego Bonaldo; Vaz, Marcelo Gomes Marçal Vieira; Fiore, Marli Fátima

    2014-03-01

    The cyanobacterial community from Brazilian mangrove ecosystems was examined using a culture-dependent method. Fifty cyanobacterial strains were isolated from soil, water and periphytic samples collected from Cardoso Island and Bertioga mangroves using specific cyanobacterial culture media. Unicellular, homocytous and heterocytous morphotypes were recovered, representing five orders, seven families and eight genera (Synechococcus, Cyanobium, Cyanobacterium, Chlorogloea, Leptolyngbya, Phormidium, Nostoc and Microchaete). All of these novel mangrove strains had their 16S rRNA gene sequenced and BLAST analysis revealed sequence identities ranging from 92.5 to 99.7% when they were compared with other strains available in GenBank. The results showed a high variability of the 16S rRNA gene sequences among the genotypes that was not associated with the morphologies observed. Phylogenetic analyses showed several branches formed exclusively by some of these novel 16S rRNA gene sequences. BLAST and phylogeny analyses allowed for the identification of Nodosilinea and Oxynema strains, genera already known to exhibit poor morphological diacritic traits. In addition, several Nostoc and Leptolyngbya morphotypes of the mangrove strains may represent new generic entities, as they were distantly affiliated with true genera clades. The presence of non-ribosomal peptide synthetase, polyketide synthase, microcystin and saxitoxin genes were detected in 20.5%, 100%, 37.5% and 33.3%, respectively, of the 44 tested isolates. A total of 134 organic extracts obtained from 44 strains were tested against microorganisms, and 26% of the extracts showed some antimicrobial activity. This is the first polyphasic study of cultured cyanobacteria from Brazilian mangrove ecosystems using morphological, genetic and biological approaches. Copyright © 2014 Elsevier GmbH. All rights reserved.

  5. 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.

  6. Marine cyanobacteria as sources of new biotechnological applications

    Directory of Open Access Journals (Sweden)

    Vitor Vasconcelos

    2014-06-01

    Bioactive compounds from cyanobacteria may also have allelopathic activity with potential use to control algal blooms or as antifouling in the marine environment (Leão et al., 2012, Antunes et al., 2013. We have isolated and characterized for the first time allelopathic compounds named Portoamides that act synergistically to prevent the growth of some microalgae (Leão et al., 2010. Cyanobacteria extracts can also prevent the development of some invertebrates such as sea urchins and mussels (Martins et al., 2007 and so they can be candidates to develop antifouling agents that are environmentally friendly. The potential of cyanobacteria as source of new bioactive compounds is enormous, with the advantage of being applicable in many different areas of biotechnology, with many industrial applications.

  7. Exploring Marine Cyanobacteria for Lead Compounds of Pharmaceutical Importance

    Directory of Open Access Journals (Sweden)

    Bushra Uzair

    2012-01-01

    Full Text Available The Ocean, which is called the “mother of origin of life,” is also the source of structurally unique natural products that are mainly accumulated in living organisms. Cyanobacteria are photosynthetic prokaryotes used as food by humans. They are excellent source of vitamins and proteins vital for life. Several of these compounds show pharmacological activities and are helpful for the invention and discovery of bioactive compounds, primarily for deadly diseases like cancer, acquired immunodeficiency syndrome (AIDS, arthritis, and so forth, while other compounds have been developed as analgesics or to treat inflammation, and so forth. They produce a large variety of bioactive compounds, including substances with anticancer and antiviral activity, UV protectants, specific inhibitors of enzymes, and potent hepatotoxins and neurotoxins. Many cyanobacteria produce compounds with potent biological activities. This paper aims to showcase the structural diversity of marine cyanobacterial secondary metabolites with a comprehensive coverage of alkaloids and other applications of cyanobacteria.

  8. Protein (Cyanobacteria) - PGDBj - Ortholog DB | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available ut This Database Database Description Download License Update History of This Database Site Policy | Contact Us Protein (Cyanobacteria) - PGDBj - Ortholog DB | LSDB Archive ... ...List Contact us PGDBj - Ortholog DB Protein (Cyanobacteria) Data detail Data name Protein (Cyanobacteria) DO...switchLanguage; BLAST Search Image Search Home About Archive Update History Data

  9. Taxon (Cyanobacteria) - PGDBj - Ortholog DB | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available of This Database Site Policy | Contact Us Taxon (Cyanobacteria) - PGDBj - Ortholog DB | LSDB Archive ... ...List Contact us PGDBj - Ortholog DB Taxon (Cyanobacteria) Data detail Data name Taxon (Cyanobacteria) DOI 10...switchLanguage; BLAST Search Image Search Home About Archive Update History Data

  10. Limited Multiplication of Symbiotic Cyanobacteria of Azolla spp. on Artificial Media

    Science.gov (United States)

    Tang, L. F.; Watanabe, I.; Liu, C. C.

    1990-01-01

    We examined various media and conditions to isolate symbiotic cyanobacteria from the leaf cavities of Azolla spp. Cyanobacteria survived and multiplied to a limited extent on a medium with fructose, Casamino Acids, yeast extract, and NaNO3 under 1% O2. These cyanobacteria were antigenically identical to the endosymbionts. Images PMID:16348366

  11. Lysogenic infection in sub-tropical freshwater cyanobacteria cultures and natural blooms

    NARCIS (Netherlands)

    Steenhauer, L.M.; Pollard, P.C.; Brussaard, C.P.D.; Säwström, C.

    2014-01-01

    Lysogeny has been reported for a few freshwater cyanobacteria cultures, but it is unknown how prevalent it is in freshwater cyanobacteria in situ. Here we tested for lysogeny in (a) cultures of eight Australian species of subtropical freshwater cyanobacteria; (b) seven strains of one species:

  12. 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.

  13. Algae production for energy and foddering

    Energy Technology Data Exchange (ETDEWEB)

    Bai, Attila; Jobbagy, Peter; Durko, Emilia [University of Debrecen, Faculty of Applied Economics and Rural Development (UD-FAERD), Centre for Agricultural and Applied Economic Sciences, Debrecen (Hungary)

    2011-09-15

    This study not only presents the results of our own experiments in alga production, but also shows the expected economic results of the various uses of algae (animal feed, direct burning, pelleting, bio-diesel production), the technical characteristics of a new pelleting method based on literature, and also our own recommended alga production technology. In our opinion, the most promising alternative could be the production of alga species with high levels of oil content, which are suitable for utilization as by-products for animal feed and in the production of bio-diesel, as well as for use in waste water management and as a flue gas additive. Based on the data from our laboratory experiments, of the four species we analyzed, Chlorella vulgaris should be considered the most promising species for use in large-scale experiments. Taking expenses into account, our results demonstrate that the use of algae for burning technology purposes results in a significant loss under the current economic conditions; however, the utilization of algae for feeding and bio-diesel purposes - in spite of their innovative nature - is nearing the level needed for competitiveness. By using the alga production technology recommended by us and described in the present study in detail, with an investment of 545 to 727 thousand EUR/ha, this technology should be able to achieve approximately 0-29 thousand EUR/ha net income, depending on size. More favorable values emerge in the case of the 1-ha (larger) size, thanks to the significant savings on fixed costs (depreciation and personnel costs). (orig.)

  14. Toolboxes for cyanobacteria: Recent advances and future direction.

    Science.gov (United States)

    Sun, Tao; Li, Shubin; Song, Xinyu; Diao, Jinjin; Chen, Lei; Zhang, Weiwen

    2018-05-03

    Photosynthetic cyanobacteria are important primary producers and model organisms for studying photosynthesis and elements cycling on earth. Due to the ability to absorb sunlight and utilize carbon dioxide, cyanobacteria have also been proposed as renewable chassis for carbon-neutral "microbial cell factories". Recent progresses on cyanobacterial synthetic biology have led to the successful production of more than two dozen of fuels and fine chemicals directly from CO 2 , demonstrating their potential for scale-up application in the future. However, compared with popular heterotrophic chassis like Escherichia coli and Saccharomyces cerevisiae, where abundant genetic tools are available for manipulations at levels from single gene, pathway to whole genome, limited genetic tools are accessible to cyanobacteria. Consequently, this significant technical hurdle restricts both the basic biological researches and further development and application of these renewable systems. Though still lagging the heterotrophic chassis, the vital roles of genetic tools in tuning of gene expression, carbon flux re-direction as well as genome-wide manipulations have been increasingly recognized in cyanobacteria. In recent years, significant progresses on developing and introducing new and efficient genetic tools have been made for cyanobacteria, including promoters, riboswitches, ribosome binding site engineering, clustered regularly interspaced short palindromic repeats/CRISPR-associated nuclease (CRISPR/Cas) systems, small RNA regulatory tools and genome-scale modeling strategies. In this review, we critically summarize recent advances on development and applications as well as technical limitations and future directions of the genetic tools in cyanobacteria. In addition, toolboxes feasible for using in large-scale cultivation are also briefly discussed. Copyright © 2018 Elsevier Inc. All rights reserved.

  15. Is Monoglucosyldiacylglycerol a Precursor to Monogalactosyldiacylglycerol in All Cyanobacteria?

    Science.gov (United States)

    Sato, Naoki

    2015-10-01

    Monogalactosyldiacylglycerol (MGDG) is ubiquitous in the photosynthetic membranes of cyanobacteria and chloroplasts. It is synthesized by galactosylation of diacylglycerol (DAG) in the chloroplasts, whereas it is produced by epimerization of monoglucosyldiacylglycerol (GlcDG) in at least several cyanobacteria that have been analyzed such as Synechocystis sp. PCC 6803. A previous study, however, showed that the mgdE gene encoding the epimerase is absent in some cyanobacteria such as Gloeobacter violaceus, Thermosynechococcus elongatus and Acaryochloris marina. In addition, the N-terminal 'fatty acid hydroxylase' domain is lacking in the MgdE protein of Prochlorococcus marinus. These problems may cast doubt upon the general (or exclusive) role of MgdE in the epimerization of GlcDG to MGDG in cyanobacteria. In addition, GlcDG is usually present at a very low level, and the structural determination of endogenous GlcDG has not been accomplished with cyanobacterial samples. In this study, I determined the structure of GlcDG from Anabaena variabilis by (1)H- and (13)C-nuclear magnetic resonance (NMR) spectroscopy. I then showed that G. violaceus, T. elongatus, A. marina and P. marinus contain GlcDG. In all cases, GlcDG consisted of fewer unsaturated molecular species than MGDG, providing further evidence that GlcDG is a precursor to MGDG. The conversion of GlcDG to MGDG was also demonstrated by radiolabeling and chase experiments in G. violaceus and P. marinus. These results demonstrate that all the analyzed cyanobacteria contain GlcDG, which is converted to MGDG, and suggest that an alternative epimerase is required for MGDG synthesis in these cyanobacteria. © The Author 2015. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  16. Hot and toxic: Temperature regulates microcystin release from cyanobacteria.

    Science.gov (United States)

    Walls, Jeremy T; Wyatt, Kevin H; Doll, Jason C; Rubenstein, Eric M; Rober, Allison R

    2018-01-01

    The mechanisms regulating toxin release by cyanobacteria are poorly understood despite the threat cyanotoxins pose to water quality and human health globally. To determine the potential for temperature to regulate microcystin release by toxin-producing cyanobacteria, we evaluated seasonal patterns of water temperature, cyanobacteria biomass, and extracellular microcystin concentration in a eutrophic freshwater lake dominated by Planktothrix agardhii. We replicated seasonal variation in water temperature in a concurrent laboratory incubation experiment designed to evaluate cause-effect relationships between temperature and toxin release. Lake temperature ranged from 3 to 27°C and cyanobacteria biomass increased with warming up to 18°C, but declined rapidly thereafter with further increases in temperature. Extracellular microcystin concentration was tightly coupled with temperature and was most elevated between 20 and 25°C, which was concurrent with the decline in cyanobacteria biomass. A similar trend was observed in laboratory incubations where productivity-specific microcystin release was most elevated between 20 and 25°C and then declined sharply at 30°C. We applied generalized linear mixed modeling to evaluate the strength of water temperature as a predictor of cyanobacteria abundance and microcystin release, and determined that warming≥20°C would result in a 36% increase in microcystin release when Chlorophyll a was ≤50μgl -1 . These results show a temperature threshold for toxin release in P. agardhii, which demonstrates a potential to use water temperature to forecast bloom severity in eutrophic lakes where blooms can persist year-round with varying degrees of toxicity. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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

  2. 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

  3. 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)

  4. A review of the alien and expansive species of freshwater cyanobacteria and algae in the Czech Republic

    Czech Academy of Sciences Publication Activity Database

    Kaštovský, J.; Hauer, Tomáš; Mareš, J.; Krautová, M.; Bešta, T.; Komárek, Jiří; Desortová, B.; Heteša, J.; Hindáková, A.; Houk, Václav; Janeček, E.; Kopp, Radovan; Marvan, P.; Pumann, P.; Skácelová, O.; Zapomělová, Eliška

    2010-01-01

    Roč. 12, č. 10 (2010), s. 3599-3625 ISSN 1387-3547 R&D Projects: GA ČR GA206/08/0318 Institutional research plan: CEZ:AV0Z60050516; CEZ:AV0Z60170517 Keywords : Microphytes * expanzive species * Czech Republic Subject RIV: EF - Botanics Impact factor: 3.474, year: 2010

  5. 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

  6. Risk Levels of Toxic Cyanobacteria in Portuguese Recreational Freshwaters

    Directory of Open Access Journals (Sweden)

    Carina Menezes

    2017-10-01

    Full Text Available Portuguese freshwater reservoirs are important socio-economic resources, namely for recreational use. National legislation concerning bathing waters does not include mandatory levels or guidelines for cyanobacteria and cyanotoxins. This is an issue of concern since cyanotoxin-based evidence is insufficient to change the law, and the collection of scientific evidence has been hampered by the lack of regulatory levels for cyanotoxins in bathing waters. In this work, we evaluate the profile of cyanobacteria and microcystins (MC in eight freshwater reservoirs from the center of Portugal, used for bathing/recreation, in order to determine the risk levels concerning toxic cyanobacteria occurrence. Three of the reservoirs did not pose a risk of MC contamination. However, two reservoirs presented a high risk in 7% of the samples according to the World Health Organization (WHO guidelines for MC in bathing waters (above 20 µg/L. In the remaining three reservoirs, the risk concerning microcystins occurrence was low. However, they exhibited recurrent blooms and persistent contamination with MC up to 4 µg/L. Thus, the risk of exposure to MC and potential acute and/or chronic health outcomes should not be disregarded in these reservoirs. These results contribute to characterize the cyanobacterial blooms profile and to map the risk of toxic cyanobacteria and microcystins occurrence in Portuguese inland waters.

  7. Inoculation effects of two South African cyanobacteria strains on ...

    African Journals Online (AJOL)

    Two South African cyanobacteria strains (coded 3g and 7e) of the genus Nostoc were evaluated for improvement of the aggregate stability of a silty loam soil with low organic C content and compared with Nostoc strain 9v isolated from a Tanzanian soil. The soil was either cropped with maize or non-cropped and inoculated ...

  8. Cyanobacteria Occurrence and Nitrogen Fixation Rates in the ...

    African Journals Online (AJOL)

    The occurrence and biological nitrogen fixation rates of epiphytic and benthic diazotrophs were studied in seagrass meadows at sites with seaweed farms and at a control site without seaweed farms from two locations, Chwaka Bay and Jambiani, along the east coast of. Zanzibar. Ten species of cyanobacteria were ...

  9. Characterization of rhizo-cyanobacteria and their associations with ...

    African Journals Online (AJOL)

    Four heterocystous cyanobacteria, belonging to the genera Anabaena and Nostoc isolated from the rhizosphere of wheat, were tested for their ability to form associations with the roots of wheat seedlings under light and dark conditions using hydroponics. The cyanobacterial strains formed close associations with wheat ...

  10. Cyanobacteria and cyanotoxins in the source water from Lake ...

    African Journals Online (AJOL)

    The phytoplankton community and cyanotoxins in Lake Chivero (formerly Lake McIlwaine) and the presence of cyanotoxins in treated drinking water were investigated between 2003 and 2004. A typical seasonal succession of Cyanobacteria species occurred from January to April, Bacillariophyta from May to July, and ...

  11. Cyanobacteria and cyanobacterial toxins in the alkaline-saline ...

    African Journals Online (AJOL)

    Physicochemical parameters, phytoplankton communities, microcystin (MC) concentrations and potential MC-producing cyanobacteria were investigated in Lakes Natron and Momela, Tanzania. In Lake Big Momela, concentrations of soluble reactive phosphorus, nitrate and ammonia were 7.1, 2.6 and 0.9 μg/L, respectively ...

  12. Engineering cyanobacteria for direct biofuel production from CO2

    NARCIS (Netherlands)

    Savakis, P.; Hellingwerf, K.J.

    2015-01-01

    For a sustainable future of our society it is essential to close the global carbon cycle. Oxidised forms of carbon, in particular CO2, can be used to synthesise energy-rich organic molecules. Engineered cyanobacteria have attracted attention as catalysts for the direct conversion of CO2 into reduced

  13. Variability of Chroococcus (Cyanobacteria) morphospecies with regard to phylogenetic relationships

    Czech Academy of Sciences Publication Activity Database

    Komárková, Jaroslava; Jezberová, J.; Komárek, O.; Zapomělová, E.

    2010-01-01

    Roč. 639, č. 1 (2010), s. 69-83 ISSN 0018-8158 Institutional research plan: CEZ:AV0Z60050516 Institutional support: RVO:67985939 Keywords : morphological variability * Cyanobacteria * reservoirs Subject RIV: DA - Hydrology ; Limnology OBOR OECD: Hydrology Impact factor: 1.964, year: 2010

  14. The cyanobacteria toxins, microcystins – emerging risks to human health

    Science.gov (United States)

    Dialysis patients appear to be at increased risk for exposure to cyanobacteria toxins; episodes of microcystin (MCYST) exposure via dialysate during 1996 and 2001 have been previously reported. During 2001, as many as 44 renal insufficiency patients were exposed to contaminated d...

  15. cyanoScope: Mapping cyanobacteria one slide at a time

    Science.gov (United States)

    cyanoScope is a new initiative for engaging the public, and particularly citizen scientists, to assist with mapping potentially harmful algal blooms throughout New England. Cyanobacteria are important members of the phytoplankton assemblages in lakes. In most situations these p...

  16. Evidence for bacterial chemotaxis to cyanobacteria from a radioassay technique

    International Nuclear Information System (INIS)

    Kangatharalingam, N.; Wang, Lizhu; Priscu, J.C.

    1991-01-01

    Lyngbya birgei and Aphanizomenon flos-aquae elicited a significant chemotactic attraction of Aeromonas hydrophila compared with controls lacking cyanobacteria. There was a positive exponential relationship between biomass (chlorophyll a) of L. birgei and A. flos-aquae and chemotactic attraction of A. hydrophila. The assay equipment was simple and reliable and could be used to study bacterial chemotaxis in other species in situ

  17. A gene expression study on strains of Nostoc (Cyanobacteria ...

    African Journals Online (AJOL)

    Cyanobacteria are well known for their production of a multitude of highly allelopathic compounds. These products have features such as incorporation of non-proteinogenic amino acids which are characteristics of peptides biosynthesized by non-ribosomal peptide synthetases (NRPSs). Some of these peptides have ...

  18. Critical assessment of chitosan as coagulant to remove cyanobacteria

    NARCIS (Netherlands)

    Lürling, Miquel; Noyma, Natalia Pessoa; Magalhães, Leonardo de; Miranda, Marcela; Mucci, Maíra; Oosterhout, Frank van; Huszar, Vera L.M.; Marinho, Marcelo Manzi

    2017-01-01

    Removal of cyanobacteria from the water column using a coagulant and a ballast compound is a promising technique to mitigate nuisance. As coagulant the organic, biodegradable polymer chitosan has been promoted. Results in this study show that elevated pH, as may be common during cyanobacterial

  19. Nodularia (Cyanobacteria, Nostocaceae): a phylogenetically uniform genus with variable phenotypes

    Czech Academy of Sciences Publication Activity Database

    Řeháková, Klára; Mareš, Jan; Lukešová, Alena; Zapomělová, Eliška; Bernardová, Kateřina; Hrouzek, Pavel

    2014-01-01

    Roč. 172, č. 3 (2014), s. 235-246 ISSN 1179-3155 R&D Projects: GA ČR(CZ) GA14-18067S; GA MŠk(CZ) ED2.1.00/03.0110 Institutional support: RVO:60077344 ; RVO:61388971 Keywords : cyanobacteria * Nodularia * taxonomy Subject RIV: EF - Botanics Impact factor: 1.318, year: 2014

  20. N-2 fixation by non-heterocystous cyanobacteria

    NARCIS (Netherlands)

    Bergman, B.; Gallon, J.R.; Rai, A.N.; Stal, L.J.

    1997-01-01

    Many, though not all, non-heterocystous cyanobacteria can fix N-2. However, very few strains can fix N-2 aerobically. Nevertheless, these organisms may make a substantial contribution to the global nitrogen cycle. In this general review, N-2 fixation by laboratory cultures and natural populations of