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Biogeneration of Volatile Organic Compounds in Microalgae-Based Systems
Published in Gokare A. Ravishankar, Ranga Rao Ambati, Handbook of Algal Technologies and Phytochemicals, 2019
Pricila Nass Pinheiro, Karem Rodrigues Vieira, Andriéli Borges Santos, Eduardo Jacob-Lopes, Leila Queiroz Zepka
Microalgae are a group of photosynthetic microorganisms typically unicellular and eukaryotic. Although cyanobacteria belong to the domain of bacteria, and are photosynthetic prokaryotes, often they are considered microalgae (Buono et al. 2014). Microalgae-based systems are considered a potentially new and valuable source of biologically active compounds for applications in several biotechnology sectors (Lauritano et al. 2018).
11C, 13N, and 15O Tracers
Published in Garimella V. S. Rayudu, Lelio G. Colombetti, Radiotracers for Medical Applications, 2019
Roy S. Tilbury, Alan S. Gelbard
Austin and co-workers76 used an enriched isotope, 13C, in the form of amorphous carbon (costing $3.50 per target), and irradiated it with 11 MeV protons at 1 μA to produce about 100 mCi of 13N. The carbon-13 target was then combusted in an automated apparatus and the 13N.N generated was collected in a small volume, having a radioactive concentration of 10 mCi/mi, higher than obtained by other methods. This was needed for their experiments on the metabolism of nitrogen gas by a cyanobacterium.77Both Austin76 and Wieland7 present calculated yields for 13N production using natural and isotopically enriched isotopes as target materials. The calculated yields are often higher than the yields achieved in practice, as quoted in Table 3. This is because of difficulties in recovering all of the generated radioisotope in the desired chemical form.
Water-based disease and microbial growth *
Published in Jamie Bartram, Rachel Baum, Peter A. Coclanis, David M. Gute, David Kay, Stéphanie McFadyen, Katherine Pond, William Robertson, Michael J. Rouse, Routledge Handbook of Water and Health, 2015
Charles P. Gerba, Gordon L. Nichols
Cyanobacteria, photosynthetic bacteria and commonly referred to as blue-green algae, grow as blooms or mats, mostly within freshwater bodies, and like dinoflagellates are called harmful algal blooms (HABs). There are a large variety of species. Many of these produce potent toxins that are capable of causing acute and chronic disease in mammals, including humans. The toxins include microcystins, nodularins, anatoxins, saxitoxins, aplysiatoxins, cylindrospremopsins, beta-methyl-amino-l-alanine (BMAA) and lipopolysaccharides (see Table 9.1 in Chapter 9). Algal blooms are more commonly found in eutrophic inland waters (eutrophic waters have a high concentration of nutrients). Human health risks arise if the water is consumed untreated, if people bathe or participate in water contact sports in waters with a scum or heavy bloom and if contaminated water is used in renal dialysis. There have been some notable outbreaks of disease associated with cyanobacterial toxins with a high mortality rate in dialysis patients. The risks through long-term exposure to contaminated drinking water may be greater than occasional recreational exposure to cyanobacterial blooms while bathing in natural waters. More information on cyanobacteria and their toxins are presented in Chapter 9.
Cyanotoxin genotoxicity: a review
Published in Toxin Reviews, 2022
Serkan Yilmaz, Taha Gökmen Ülger, Bayram Göktaş, Şahlan Öztürk, Duygu Öztaş Karataş, Ebru Beyzi
Cyanobacteria, which can also be named under different names, such as cyanoprocaryotes, cyanophytes and blue-green algae, are prokaryotic organisms without real nuclei and plastids, they differ from other algae groups due to their prokaryotic structure, and they have common features with other algae due to their photosynthesis (Palinska and Surosz 2014). Approximately 2000 strains of cyanobacteria belonging to approximately 150 specıes have been identified on earth, and these strains can be found colonially in all kinds of habitats from seas, soil, hot waters to cold surfaces (Pulz and Gross 2004). Cyanobacteria, which have important ecological roles in the carbon and nitrogen cycles, especially Spirulina, Anabaena, Nostoc and Oscillatoria genus, produce many secondary compounds with peptide, alkaloid and polysaccharide structure (Singh 2016). Though some of the secondary metabolites can be used as therapeutic raw materials because of their antitumor, antifungal and anti-inflammatory effects and siderophores, phytohormones, photoprotective compounds and protease inhibitors (Sinha and Häder 2008), some toxins show negative effects on health due to their hepatotoxic, dermatoxic, neurotoxic, cytotoxic and genotoxic effects (De La Cruz et al. 2020). To date, up to 40 cyanobacterial strains have been identified as generating potential cyanotoxin production in surface water and the main strains in this group are Anabaena, Aphanizomenon, Microcystis, Nodularia and Cylindrospermopsis (Cirés et al. 2017).
An overview on cyanobacterial blooms and toxins production: their occurrence and influencing factors
Published in Toxin Reviews, 2022
Isaac Yaw Massey, Muwaffak Al osman, Fei Yang
The ancient cyanobacteria organisms, noticeable in rocks dating from the first thousand million years of the earth’s history and belong to the kingdom monera (Prokaryota), division eubacteria and class cyanobacteria (Ressom et al.1994, Omidi et al.2018), are a type of photosynthetic bacteria that live in water surface. As cyanobacteria colonies occur in shallow water, they appear in the fossil record in sedimentary rocks deposited in shallow seas and lakes. Cyanobacteria colonies identified as stromatolites emerge in rocks as fossilized mushroom shapes and sheets. Falconer (2005) reported that the Gunflint chert was one of the best stromatolite formations known in Lake Erie. It is of interest cyanobacteria was shown to possess a single circular chromosome completely sequenced in several species, plasmids and small circular strands of DNA (Schwabe 1988, Kaneko et al.1996). Whitton and Potts (2000) found that the chlorophyll-a and pigment phycocyanin observed in cyanobacteria photosynthetic membranes were responsible for the characteristic blue-green color of the many species. Pigments such as carotenoids and phycoerythrin which give a strong red color to some species may also be present (Bryant 1994).
Biofilm diversity, structure and matrix seasonality in a full-scale cooling tower
Published in Biofouling, 2018
L. Di Gregorio, R. Congestri, V. Tandoi, T. R. Neu, S. Rossetti, F. Di Pippo
Alphaproteobacteria were prevalent in summer, representing 49.8% of the total OTUs, with the majority of species belonging to family Rhizobiaceae (17.9%, mainly Rhizobium and Ensifer), Bradyrizobiaceae (6.9%) and Sphingomonadaceae (6.5%). Summer biofilms (Bi-Su) also had a relevant percentage of Betaproteobacteria (15.6%), mainly Cupriavidus sp. (12%, Burkholderiaceae). OTUs affiliated to phototrophs were also abundant (chloroplasts 23.8% and cyanobacteria 3.5%). Green algae were mainly represented, again, by Vischeria sp., Kirchneriella sp., Scenedesmus sp., Stigeoclonium sp. and Cladophora sp. (Figure 2). In addition, the presence of the chain-forming diatom Diadesmis sp. and that of raphid species of Navicula and Nitzschia was recorded. A minor contribution to the phototrophic component was due to coccal cyanobacteria including Cyanobacterium sp., Cyanothece sp., Pleurocapsa sp. and Synechocystis sp., while filamentous cyanobacteria belonging to Microcoleus sp. and Phormidium spp. were rare.