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Copyright of Environmental & Social Management Journal / Revista de Gestão Social e Ambiental is the property of Environmental & Social Management Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Se desarrolló una revisión bibliográfica a través de la consulta de diversas fuentes de información (artículos, libros, resúmenes, etc.) obtenidas de diversas bases de datos como Web of Science, Scopus y Biological abstracts, entre otras. Se describen de forma cronológica los estudios más relevantes de las últimas tres décadas, partiendo de investigaciones históricas, así como tópicos actuales bajo diversos subtemas; se analizaron críticamente cerca de 200 de artículos con el objetivo de exponer de manera sencilla, pero explícita, las características generales de las cianobacterias; las principales condiciones que favorecen la formación y persistencia de los florecimientos o “CianoFANs”; las implicaciones negativas sobre los recursos hídricos debido a la producción de cianotoxinas, con énfasis en los límites de referencia establecidos para la hepatotoxina microcistina-LR en agua de consumo humano, en sistemas de uso recreativo y en productos alimenticios; las metodologías desarrolladas para el monitoreo de cepas tóxicas, y un resumen de las investigaciones publicadas en México sobre cianobacterias y sus toxinas. Por último, se discuten algunos procedimientos de control usados en remediación de sistemas con proliferación de cianobacterias.

Las floraciones cianobacterianas en cuerpos de agua son un problema de gran interés entre la comunidad científica, debido a la producción de metabolitos tóxicos, denominados cianotoxinas. Las cianobacterias están formadas por un amplio número de géneros y especies, con diversos mecanismos de intoxicación; por lo que constituyen un grave problema ambiental con serias repercusiones en la salud de los seres vivos y del hombre. Adicionalmente, la alta producción de cianotoxinas asociada a la presencia de cianobacterias ha crecido enormemente en frecuencia y extensión en todo el mundo, lo cual aumenta la preocupación por parte de las autoridades y los prestadores de servicios públicos. Por otro lado, es importante señalar que los procesos convencionales con los que operan las instalaciones de tratamiento de agua son ineficientes para su eliminación y/o degradación dado que las cianotoxinas son solubles en agua y persistentes. En este sentido, se hace necesaria la aplicación de tecnologías alternativas a los sistemas de tratamiento tradicionales de potabilización con el fin de obtener un agua de calidad apta para el consumo humano. En el presente trabajo, se describe el uso de ultrasonido en el tratamiento de aguas contaminadas con cianobacterias y cianotoxinas, haciendo especial hincapié en la influencia de la variación de parámetros significativos que intervienen en la eficiencia de eliminación e inactivación de las cianobacterias, y la degradación de sus toxinas a través del proceso de sonicación. Con ello, se pretender posicionar el ultrasonido de baja frecuencia como tecnología de oxidación avanzada que permita controlar la proliferación de las cianobacterias y sus toxinas, y evitar la reducción de la calidad de los cuerpos de agua que abastecen las plantas de producción de agua potable.

Se evaluó el efecto en la nutrición de la sustitución de la harina de pescado por la de cianobacteria S. subsalsa en un cultivo de caracol manzana Pomacea bridgesii, donde se utilizaron 60 organismos a los cuales se les suministraron dos dietas (A y B) de alimento balanceado: una adicionada con harina de S. subsalsa (A) y la otra sin S. subsalsa con harina de pescado (B). El cultivo se realizó en un sistema de recirculación conformado por seis unidades de cultivo, durante un periodo de diez semanas. Para evaluar la eficiencia de las dietas se utilizó la tasa de crecimiento absoluta (TAC), con un valor de 0,168 ± 0,011 para A y 0,162 ± 0,009 para B, la tasa de crecimiento específica (TEC), con un valor de 1,417 ± 0,013 para A y 1,416 ± 0,065 para B, en cuanto al factor de conversión alimenticia (FCA), se obtuvo un valor de 1,52 ± 0,11 para A y 1,33 ± 0,08 para B. Se realizó un análisis de varianza para la TAC y TEC, entre los tratamientos A y B, sin encontrar diferencias significativas. El análisis de medidas repetidas para peso y talla, entre los tratamientos A y B, no mostró diferencias significativas, con esto se puede decir que, en la dieta (dieta A) en la que se sustituyó una porción de harina de pescado por harina de S. subsalsa, ofreció los mismos resultados que la dieta elaborada con harina de pescado (dieta B) como principal fuente de proteína. Por lo que se podría reducir el uso de la harina de pescado en la formulación de alimentos acuícolas al menos para esta especie de caracol.

Copyright of Tecnología y Ciencias del Agua is the property of Instituto Mexicano de Tecnologia del Agua (IMTA) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Salud, Ciencia y Tecnología is the property of Fundacion Salud, Ciencia y Tecnologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The production of microbial biomass can be affected by the composition of the culture medium, including the content of salts and there is little information in terms of the NaCl concentration. Therefore, in this study, the effect of the addition of different NaCl concentrations (0.0, 2.0, 2.5, and 3.0 g L-1) in a Jourdan medium was evaluated on cell growth and physical and chemical properties of Arthrospira maxima cultivated in the region of Cordoba, Veracruz, Mexico. The experiment was established under a completely randomized design with a factorial arrangement (AxB). During the production stage, cell growth and morphology of filaments were evaluated, and after harvesting, the physical and chemical analysis (moisture, crude fiber, total protein and lipid content, mineral composition, photosynthetic compounds, antioxidant activity, and structural composition through FTIR-Spectroscopy analysis) of A. maxima was performed. Results obtained show that the addition of NaCl did not affect cell development, the morphology of the filaments, or the content of photosynthetic compounds. The maximum rate of biomass production in all treatments was at 6 d, without significant differences (p > 0.05) among treatments. In all treatments, A. maxima showed adequate concentrations of protein and minerals, as well as antioxidant activity. FTIR spectra showed absorption bands associated with proteins, carbohydrates, lipids, and nucleic acids. A decrease in the amide I and amide II bands of the proteins was observed with the addition of NaCl. A. maxima cultivated in these tropical climatic conditions had excellent properties to be used as a functional ingredient in the development of innovative and biotechnological food products for human consumption. [ABSTRACT FROM AUTHOR]

El presente trabajo reporta por primera vez para el Perú a la cianobacteria bentónica Lemmermanniella uliginosa, identificada en muestras de perifiton y sedimentos bentónicos procedentes del humedal de Caucato en el distrito de San Clemente, departamento de Ica. Además, se registra por primera vez al género Lemmermanniella para el país. Se discuten aspectos morfo-taxonómicos de la especie comparándola con poblaciones reportadas para otras localidades en zonas tropicales.

Introduction: The 135 km² Cerrón Grande reservoir is the largest wetland in El Salvador, recognized as “Wetland of International Importance” by the Ramsar Convention. It is also one of the most polluted ecosystems nationwide, facing serious problems, among them, a proliferation of cyanobacteria. Objective: To assess the relationships among environmental factors and the spatial and temporary distribution of cyanobacteria in the reservoir throughout a hydrological year. Methods: We extracted water with cyanobacteria from six fixed sites, from October 2018 through September 2019. Results: We identified 16 genera, the most abundant Microcystis sp. And Dolichospermum sp.; Microcystis sp. reached 1.5 x 106 cells/ml in June 2019, mainly in the north-west sector, which is shallow and close to the confluence zones where highly polluted tributaries reach the reservoir. The deeper south-east sector had low concentrations of these organisms. The environmental factors mostly related to this behavior were: phosphorus, electrical conductivity and Secchi value, as expected from a eutrophic body. Conclusions: Variation in the cellular concentration of cyanobacteria in this reservoir is highly influenced by rain, water mixing and nutrient content. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

El objetivo de la presente investigación fue evaluar el crecimiento y el contenido de pigmentos de un nuevo aislado de Spirulina subsalsa cultivada en agua mar a diferentes salinidades y concentraciones de nitrógeno. La nueva cepa de S. subsalsa se aisló a partir de muestras de agua procedentes del embalse de Clavellino, estado Sucre, Venezuela, y fue identificada haciendo uso de la clave taxonómica propuesta por Aguiar (2013). El medio de cultivo ensayado fue el f/2, modificando las concentraciones de nitrato (14,5; 29 y 58 mmol/L) y cloruro de sodio (0, 9 y 18 ‰ por adición de agua de mar). Los cultivos se realizaron por triplicado, de forma discontinua, bajo condiciones de medio ambiente controlado (T: 30±1 ºC; iluminación: 3.000 lux; agitación manual, fotoperiodo 12:12), durante 21 días. Los resultados obtenidos evidenciaron que la salinidad de 9 ‰ y la concentración de nitrato de 14 mmol/L fueron los parámetros que propiciaron los mayores contenidos de biomasa; mientras que la clorofila a y la ficocianina mostraron mayores valores en la misma concentración de nitrógeno, pero a 0 ‰. Estos hallazgos indican que la salinidad y la concentración de nitrógeno afectan el crecimiento y los pigmentos del nuevo aislado de S. subsalsa y además sugieren que esta cepa posee potencial para su aprovechamiento biotecnológico con miras a obtener metabolitos valiosos en las industrias alimenticias y farmacológicas.

Copyright of Revista Ambiente e Água is the property of Revista Ambiente e Agua and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A qualidade da água dos reservatórios de abastecimento público do Estado de Pernambuco vem sendo comprometida, no que concerne a seu padrão de potabilidade, isto se deve ao intenso processo de eutrofização. Este processo de enriquecimento das águas prejudica os usos múltiplos dos reservatórios, principalmente pelo fato de propiciar o desenvolvimento de florações de cianobactérias potencialmente produtoras de cianotoxinas que podem afetar a saúde de muitos animais, inclusive do homem. Deste modo, o presente estudo teve como objetivo realizar o levantamento taxonômico das cianobactérias e determinar a concentração de cianotoxinas pelo método imunoenzimático (ELISA) nos reservatórios de Jucazinho e Carpina, situados no Agreste e na Zona da Mata Norte do Estado de Pernambuco, respectivamente. As amostras foram coletadas com frequência mensal, durante os meses de setembro a dezembro de 2014, na região limnética próximo ao ponto de captação dos reservatórios. Foi relatada a ocorrência de florações de cianobactérias potencialmente produtoras de cianotoxinas em amostras de água dos reservatórios estudados. Contudo, as concentrações de cianotoxinas em ambos os reservatórios ficaram abaixo dos valores máximos permissíveis estabelecidos na portaria MS 2.914/2011. Diante de tais resultados, a ocorrência de “blooms” tóxicos de cianobactérias nos reservatórios em estudo aponta um risco permanente de cianotoxinas e indica a necessidade da implementação de medidas de controle das florações, visando à melhoria da qualidade das águas.

Una de las especies de "malezas" más problemáticas en los viveros de Florida es Nostoc, una cianobacteria que se encuentra comúnmente en los caminos de grava, pasillos, telas de tierra y en muchas otras áreas de producción. Las colonias de Nostoc están compuestas por cadenas de cianobacterias que crecen en la superficie del suelo, la grava y el cemento con el crecimiento suficiente para producir grandes colonias macroscópicas. Cuando está seco, Nostoc se vuelve escamoso y apenas se nota. Cuando se introduce humedad a través del riego o la lluvia, Nostoc se hincha para formar masas espesas, de color verde oscuro y gelatinosas que pueden cubrir completamente las áreas de producción de contenedores. Si bien es muy desagradable, la principal preocupación de esta especie es que es extremadamente resbaladiza y húmeda. Como es común en los pasillos y en las áreas de producción de contenedores, Nostoc presenta serios riesgos para la salud de los empleados del vivero. En los últimos años, esta especie se ha convertido en la pesadilla de los administradores de viveros, ya que no se han desarrollado medidas de control efectivas. Otras preocupaciones son su capacidad para producir cianotoxinas y compuestos alelopáticos. El objetivo de esta investigación fue abordar el dilema de Nostoc utilizando una combinación de metodología de laboratorio y de campo para evaluar la eficacia de los tratamientos químicos para proponer a los productores una solución de manejo eficaz de Nostoc.

Arthrospira sp. is an aquatic and photosynthetic microorganism that is extensively employed as a food supplement due to its rich contents of nutrients, proteins, and carbohydrates. In this study, a local strain of cyanobacterium of the genus Arthrospira was isolated from the Iraqi soil, in the region of Mosul city, using the Chu's Medium No. 10. The growth rate, as well as the effects on biomass and cellular component contents of proteins, carbohydrates, and chlorophyll of this strain, were evaluated on the molasses medium alone or supplemented with iron, copper, nickel, cadmium and cobalt salts after fifteen days of incubation. The results showed that the best growth rate (1.09 OD), the highest value of biomass (120.0 mg/l), proteins content (297.2 mg/l), chlorophyll content (14.9 mg/l) and carbohydrates content (400.0 mg/l) of Arthrospira sp. was achieved after fifteen days of incubation. Generally, it was observed that adding iron, copper, nickel, cadmium, and cobalt salts into the molasses medium increased the contents of biomass, proteins, and carbohydrates of Arthrospira sp. It was noticed that the highest biomass concentration (1960 mg/l) was obtained when Arthrospira sp. grown on molasses medium supplemented with nickel. Also, none of the metal salts added to the molasses medium increased the protein content of Arthrospira sp. Conversely, adding copper, nickel, and cobalt to the medium showed an adverse effect on the protein content. It was shown that adding iron metal salts into the molasses medium increased the carbohydrates and the chlorophyll contents of Arthrospira sp.. These results suggest that Arthrospira sp. can be utilized for the bioremediation of heavy metals pollution in the environment and industrial sites. [ABSTRACT FROM AUTHOR]

Copyright of Orinoquia is the property of Universidad de los Llanos and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Investigación e Innovación en Ingenierías is the property of Universidad Simon Bolivar and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Arthrospira maxima, known globally as spirulina, is highly cultivated for its protein, vitamin and phycobiliprotein content, which makes it considered a superfood. Cyanobacteria extracts provide a more sustainable option in food production compared to synthetic fertilizers; however, there are no reports of its potential as a biofertilizer in some crops such as Stevia rebaudiana. The objective of this work was to evaluate an extract of A. maxima on the initial growth stage of S. rebaudiana under house vegetation conditions. A completely randomized design (CRD) was used with 4 treatments, corresponding to concentrations of 0, 4, 8 and 12 mg mL-1 of A. maxima and a control. The variables evaluated were the main gas exchange parameters and biomass distribution. The main results showed that concentrations of 4, 8 and 12 mg mL-1 of the extract increased net photosynthesis rates (30.5%, 23.8% and 65.9%), stomatal conductance (41.8%, 8.6% and 64.7%) and transpiration (37.2%, 18.1% and 75.5%), compared to the control in S. rebaudiana. In addition, S. rebaudiana showed a greater ability to distribute biomass to the stem with applications of the high concentration of the extract. According to the results obtained, the extract of A. maxima has a great agricultural potential in the initial growth stage of S. rebaudiana by improving the physiological indicators studied. [ABSTRACT FROM AUTHOR]

Microalgae and cyanobacteria are rich in compounds with a wide diversity of biological activities that can be used to create new products with promising applications by the cosmetic industry. Many studies evaluating the bioactivities of microalgae and cyanobacteria extracts have been published, however perception of their potential use in cosmetic applications is still limited. The objective of this study was to systematically review the recent literature to assess the potential applications of microalgae and cyanobacteria in cosmetics. A total of 8498 articles mentioning antioxidant or anti-inflammatory properties, or cosmetic or nanosystem applications of microalgae and cyanobacteria extracts or biomass in the past 5 years were retrieved from different databases and the eligibility process was conducted applying inclusion and exclusion criteria. After that, 151 papers were selected of which 61 % cited antioxidant properties, 19 % cosmetic applications, 14 % anti-inflammatory potential, and 6 % nanosystem applications. The most reported genera were Chlorella (7 %), Arthrospira (7 %), Tetraselmis and Scenedesmus (6 % each). Crude extracts or biomass (56 %), pigments (14 %) and polysaccharides (9 %) were the type of microalgae- and cyanobacteria-based products most reported, Ninety-six percent of articles used in vitro methods with in vitro non-cellular assays being most cited (79 %) when compared with cellular assays (21 %), and only 4 % used in vivo approaches. Considering cosmetic applications, photoprotection (43 %), anti-cancer (melanoma) (19 %), and wound healing (16 %) were the most reported. A limited number of studies reported nanosystem applications, with metal nanoparticles and nanoemulsions as the most common nanosystem. The evidence found in the literature suggest that microalgae and cyanobacteria extracts are rich sources of bioactive products and compounds for cosmetic industry, which potential is far from being fully explored. [Display omitted] • Microalgae and cyanobacteria display relevant bioactivities for cosmetics. • Microalgae and cyanobacteria are potential functional cosmetic ingredients. • Biodiversity of microalgae and cyanobacteria is far from being explored. • Microalgae and cyanobacteria have nanobiotechnological potential. • Nanobiotechnologies will increase the efficiency of cosmetic application. [ABSTRACT FROM AUTHOR]

As cianobactérias representam um componente natural da comunidade fitoplanctônica, mas estão frequentemente associadas com águas eutrofizadas. Os rios do estado de São Paulo estão em processo contínuo de eutrofização, o que favorece frequentes florações de cianobactérias, prejuízos à qualidade da água para o consumo humano e riscos à biota aquática. O mexilhão dourado (Limnoperna fortunei) é uma espécie exótica invasora que pode ser vetor na transferência de toxinas de cianobactérias. O objetivo deste estudo foi avaliar a ocorrência de florações de cianobactérias no rio São José dos Dourados, suas toxinas produzidas e a possibilidade de ficotoxinas bioacumularem em Limnoperna fortunei. Foram detectadas, nas amostras, a dominância de cianobactérias tóxicas e cianotoxinas (microcistinas). Os resultados indicaram que L. fortunei acumularam microcistinas. As florações de cianobactérias nas águas do rio estudado indicaram prejuízo ao ambiente associado à eutrofização e aos riscos da presença das cianotoxinas à biota aquática.

La ecorregión del Monte Central posee un elevado déficit hídrico. La escasez y variabilidad del recurso agua condiciona la distribución espacial de las plantas vasculares. Aquellas zonas desprovistas de vegetación se encuentran comúnmente colonizadas por comunidades microbióticas (musgos, cianobacterias, líquenes) denominadas costras biológicas de suelo (CBS), que modifican numerosas propiedades biogeoquímicas del sustrato. Uno de los constituyentes fundamentales de las CBS son las cianobacterias, que sintetizan clorofila a, ficobilinas y fijan nitrógeno (N) atmosférico, representando una de las fuentes principales de N para alguno de los ecosistemas áridos. El objetivo de este trabajo es contribuir al conocimiento de las cianobacterias presentes en biocostras del desierto del Monte central, en distintas unidades de paisaje del Este de Mendoza (reservas naturales y áreas pastoreadas). Se realizaron colectas de material biótico y abiótico durante los años 2015 y 2016 en cada unidad ambiental. Para la identificación de las cianobacterias se utilizaron características morfológicas observadas con microscopía óptica, y claves taxonómicas. De esta manera se dan a conocer 12 nuevos registros de cianobacterias en CBS, que permitirán ampliar el conocimiento de las biocostras, su distribución geográfica y ecología en la provincia de Mendoza.

Abstract Aim: Reveal the direction for future studies about eutrophication, or even reveal the preoccupation among the scientific community about this environmental problem. With a systematic synthesis of eutrophication studies, scientists may be able to understand the state of the literature on aquatic ecosystems around the world. This study intends to identify the main factors used to control algal blooms and the eutrophication process, the countries and environments which have more research about this theme or even identify the articles’ subjects in different periods (e.g.: Experimental, theoretic, monitoring, conservation). Methods We analyzed all studies published in the Thomson ISI Web of Science on both eutrophication and phytoplankton between 2001 and 2016. Results During the period analyzed, we observed an increase in concern about this subject. Authors from institutions in the USA and China wrote most of the studies. The most important geographic and socioeconomic aspects to determine the publication number were total area and HDI respectively. However, the main determinant for the publication about this subject was international collaboration. Some of the most actual themes in ecology and conservation (e.g.: functional groups, climate change, experiment, perdition models, regional scales, invasive species) were addressed in the studies analysed. Invasive species such as Tilapia and Cylindrospermopsis raciborskii were the most cited species on these keywords. Conclusion Despite the current issues addressed in the studies on phytoplankton and eutrophication, some subjects, such as climate change or spatial pattern, were only common in years more recent. Even though studies focusing in functional diversity are highly relevant for conservation, they were not common in any year studied. The major determinant factor related to the increasing in eutrophication knowledge was the international collaboration

Se han preparado 3 vidrios con distinto contenido en SiO2 y de composición similar a los nutrientes necesarios para el crecimiento del alga Spirulina platensis. Se han escogido 2 fracciones con distinto tamaño de partícula para cada uno de los vidrios preparados y la cinética de lixiviación de dichos vidrios ha sido estudiada a través del análisis químico de las aguas de lixiviado, permitiendo obtener las curvas de velocidad para cada uno de los componentes del vidrio. A partir del cálculo de la constante de velocidad y del exponente de la reacción de lixiviado, se ha realizado una aproximación al crecimiento del alga Spirulina platensis en condiciones ambientales normales de luz, pH y temperatura y se ha obtenido que, a través de la modificación de la composición del vidrio de partida o de su tamaño de partícula, es posible ajustar el aporte de nutrientes al medio a la velocidad de crecimiento del alga Spirulina platensis.

AimTo determine the composition and biomass of functional groups around the vertical and temporal gradient correlated with environmental conditions and apply the index Q in a water-supply reservoir.MethodsWater samples were collected monthly (n = 92) between 2009 and 2011 in two points of the dam for physicochemical and biological analysis.ResultsThe pH, dissolved oxygen and water temperature showed significant differences between the photic and aphotic zones (p

Aim:The rapid spread of cyanobacteria in water sources and reservoirs has caused serious environmental damage and public health problems, and consists in a problem that challenges the institutions responsible for providing water to the population. In this study, the quantification of microcystin, saxitoxins and cyanobacteria levels was performed over 3 years in the semi-arid reservoirs of Rio Grande do Norte (Brazil). In addition, we analyzed the seasonal distribution of cyanotoxins and the percentage of cyanobacteria and cyanotoxins which were above the limit established by Brazilian law.MethodsThe study was conducted between 2009 and 2011 in four dams with six sites: Armando Ribeiro Gonçalves (ARG) in Itajá, San Rafael (SR) and Jucurutu; Passagem das Traíras (PT); Itans and Gargalheiras (GARG). Cyanobacteria presence were quantified and identified and the presence of microcystins (MCYs) and saxitoxins (STXs) was investigated by ELISA.ResultsThe densities of cyanobacteria were found to be above the permitted in 76% of cases. The ELISA results showed that of the 128 samples analyzed, 27% were above the maximum allowed by the Brazilian Ministry of Health Order 2914/2011. A seasonal pattern for the presence of MCYs was found (0.00227 to 24.1954 µg.L–1), with the highest values in the rainy season. There was no clear seasonal pattern for STXs (0.003 to 0.766 µg.L–1).ConclusionsThis study showed the importance of establishing a water quality monitoring for human consumption and its potability standards since the concentration of MCYs in some samples was above the maximum limit allowed by Brazilian law, thus posing a risk to public health since the conventional water treatment is not able to eliminate these potent hepatotoxins.

Copyright of Lilloa is the property of Fundacion Miguel Lillo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Microorganisms may play an important role in the binding of sediments and the formation of sedimentary structures, by means of the formation of biofilms and microbial mats. In this work, filamentous cyanobacteria from three different environments were compared: a biofilm from a lacustrine environment with intervals of flooding/desiccation, a biofilm from a continental saline environment, and a microbial mat from a thermal spring. The optical identification of the cyanobacteria allowed to establish that in the biofilms there is a dominance of the Order Oscillatoriales, while in the microbial mat both cyanobacteria of the Orders Nostocales and Oscillatoriales dominated. Two rock samples isolated from the thermal spring which genesis was possibly influenced by the activity of cyanobacteria are described and classified. One of them is a travertine/microbial framestone with stromatolitic and thrombolytic texture. The second one is classified as a mudstone/microbial boundstone. Finally, a comparison between the sedimentary structures identified in those rocks with similar structures in the formations La Luna, Paja and Tetuán, deposited during regressive phases of the Colombian Cretaceous epyric sea, and microbial mat features previously described is performed. Based on morphological resemblance, fibrillar networks identified locally in those formations are interpreted as possible biolaminations originated from the activity of cyanobacteria. [ABSTRACT FROM AUTHOR]

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This research analyzed three green microalgae (Scenedesmus sp., Chlamydomonas sp., and Chlorella sp.) and two cyanobacteria (Synechocystis sp. as unicellular strain and Nostoc sp. as filamentous strain) native from Costa Rica to remove high concentrations of ammonium and phosphate. Cultures were exposed for 120 h to initial concentrations of 70 mgL-1 ammonium and 9 mgL-1 phosphate, under constant light intensity of 60 µmol m-2s-1. Chlorella sp. showed the highest growth rate, followed by Chlamydomonas sp. and the cyanobacteria Nostoc sp. In contrast, Scenedesmus sp. and Synechocystis sp. cultures grew less than the other ones. The highest percentage of ammonium removal was achieved with Chlorella sp. followed by Chlamydomonas sp. and Synechocystis sp., then Scenedesmus sp. and Nostoc sp. Microalgae removed totally the initial phosphate concentration within 72 h, while cyanobacteria Synechocystis sp. and Nostoc sp. removed phosphate partially. These microorganisms are promising for wastewater reclamation. [ABSTRACT FROM AUTHOR]

Expansion of aquaculture around the world has heavily impacted the environment. Because fertilizers are needed to raise fish, one of the main impacts is eutrophication, which lowers water quality and increases the frequency of algal blooms, mostly cyanobacteria. To evaluate whether the water quality in 30 fishponds in southeastern Brazilian met the requirements of Brazilian legislation, we analyzed biotic and abiotic water conditions. We expected that the high nutrient levels due to fertilization would cause low water quality. We also analyzed cyanotoxins in seston and fish muscle in some systems where cyanobacteria were dominant. The fishponds ranged from eutrophic and hypereutrophic with high phytoplankton biomass. Although cyanobacteria were dominant in most of the systems, cyanotoxins occurred in low concentrations, possibly because only two of the 12 dominant species were potential producers of microcystins. The high phosphorus concentrations caused the low water quality by increasing cyanobacteria, chlorophyll-a, turbidity, and thermotolerant coliforms, and by depleting dissolved oxygen. We found that all the 30 systems were inappropriate for fish culture, according to Brazilian legislation, based on at least one of the parameters measured. Furthermore, there was not any single system in the water-quality thresholds, according to the Brazilian legislation, to grow fish. Our findings indicate the need for better management to minimize the impacts of eutrophication in fishponds, in addition to a rigorous control to guarantee good food.

Nowadays algal biofuels are considered one of the most promising solutions of global energy crisis and climate change for the years to come. By manipulation of the culture conditions, many algal species can be induced to accumulate high concentrations of particular biomolecules and can be directed to the desired output for each fuel. In this context, the present study involved the assessment of the effects of CO2 availability and nitrogen starvation on growth and chemical composition of the cyanobacterium Synechococcus subsalsus, testing a fast-growing native strain. The control experiments were performed with Conway culture medium in 12-day batch cultures, in 6-liter flasks and 12 h photoperiod, with addition of 2 L min-1 filtered air to each flask. Other two experimental conditions were also tested: (i) the placement into the cultures of additional dissolved nutrients except nitrogen, one week after the start of growth (N-), and (ii) the input of pure CO2 into the flasks from the 5th day of growth (C+). In all cultures, daily cell counts were done throughout the cultivation, as well as measurements of pH and cell biovolumes. Maximum cell yield were found in N-experiments, while cell yields of C+ and control were similar. Dissolved nitrogen was exhausted before the end of the experiments, but dissolved phosphorus was not totally consumed. Protein and chlorophyll-a concentrations decreased from the exponential to the stationary growth phase of all experiments, except for protein in the control. In all experiments, carbohydrate, lipid and total carotenoid increased from the exponential to the stationary growth phase, as an effect of nitrogen limitation. Increments in carbohydrate concentrations were remarkable, achieving more than 42% of the dry weight (dw), but concentrations of lipid were always lower than 13% dw. The addition of pure CO2 did not cause a significant increase in biomass of S. subsalsus nor generated more lipid and carbohydrate than the other treatments. Nitrogen starvation caused an intense accumulation of carbohydrate, but the increments of lipid were small. Despite the fast growth, the cyanobacterium S. subsalsus has a virtually null potential for biodiesel production, given its low lipid concentrations. The high concentrations of carbohydrate combined with fast growth point to the potential use of this species as raw material for other possible biotechnological processes, after a demonstration of technical and economic viability.

Cyanobacteria biodiversity researches are carried out in various types of soils of the Astrakhan region. The qualitative and quantitative structure сyanobacteria and seaweed the investigated soils is shown.

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

O trabalho relata a ocorrência de algas indicadoras de processos de eutrofização no Saco do Laranjal (Lagoa dos Patos) no período compreendido entre 2005 e 2012. A ocorrência de grandes quantidades da alga macroscópica verde Ulva L. (Chlorophyta), formando marés verde, foram registradas nos verão de 2008, 2009 e 2012. A cianofícea potencialmente tóxica, Microcystis aeruginosa (Kütz.) Kütz. foi observada em quase todos os anos, nos meses de verão e, em floração massiva, no verão de 2010. São fornecidas ilustrações dos eventos de crescimento massivos observados. Os resultados sugerem que o Saco do Laranjal provavelmente apresenta-se em processo de eutrofização.

Título en ingles: Growth and biochemical composition of Limnothrix sp. at different salinities and concentrations of nitrateTítulo corto: Crecimiento y composición bioquímica de Limnothrix sp.ResumenSe evalúo el efecto de la salinidad (15, 25 y 35 UPS) y concentración de nitrato (4, 8 y 16 mmoles L-1) sobre el crecimiento y composición bioquímica de la cianobacteria Limnothrix sp. (LAEP- 52) con miras a su explotación para fines biotecnológicos. La cianobacteria se cultivó durante 20 días a 25°C, 98 µmol m-2s-1, fotoperiodo 12:12 y aireación continua (200 mL min-1). El crecimiento fue evaluado cada 48 horas a través de la medición de la densidad óptica a 730 nm. Se evidenció que la salinidad y la concentración de nitrato modulan el crecimiento y la composición bioquímica de Limnothrix sp. El mayor crecimiento (6.3 ± 0.38 mg mL-1), contenidos de proteínas (57 ± 4.56 %), ficocianina (170.3 ± 13.6 µg mL-1) y clorofila a (16 ± 1.28 µg mL-1) se obtuvieron a la menor salinidad (15 UPS) y mayor concentración de nitrato (16 mmoles L-1). Por el contrario, las mayores concentraciones de lípidos (21.3± 1.19 %), carbohidratos (14.47 ± 1.15 %) y carotenoides (6 ± 0.48 µg mL-1) se lograron en la mayor salinidad (35 UPS) y menor concentración de nitrato (4 mmoles L-1). La producción de exopolisacáridos sólo fue influenciada por la salinidad, llegando a alcanzar sus mayores valores a 35 UPS (1600 ± 112.25 mg L-1). Los contenidos de proteínas, lípidos, carbohidratos y pigmentos obtenidos en esta cianobacteria permiten catalogarla como un organismo que puede ser usado en las industrias biotecnológicas, ya sea como alimento para organismos cultivados o como fuente de metabolitos de interés industrial. Palabras clave: cianobacteria, biotecnología, LimnothrixAbstractIn this research we evaluate the effect of salinity (15, 25 and 35 UPS) and nitrate concentration (4, 8 and 16 mmoles L-1) on growth and biochemical composition of the cyanobacterium Limnothrix sp. (LAEP-52) with a view to exploitation for biotechnological purposes. The cyanobacterium was grown in volumes of 1 L for 20 days. The culture conditions included 25 °C, irradiance of 98 µmol m-2 s-1, photoperiod 12:12 and continuous aeration (200 mL min-1). Growth was evaluated every 48 hours through the measurement of optical density at 730 nm. It showed that salinity and concentration of nitrate modulate the growth and biochemical composition of Limnothrix sp. The highest values of growth (6.3 ± 0.38 mg mL-1), protein content (57 ± 4.56%), phycocyanin (170.3 ± 13.6 mg mL-1) and chlorophyll a (16 ± 1.28 mg mL-1) were obtained at the lowest salinity (15 UPS) and highest levels of nitrate (16 mmolesL-1). By contrast, higher concentrations of lipids (21.3 ± 1.19%), carbohydrate (14.47 ± 1.15%) and carotenoids (6 ± 0.48 mg mL-1) were achieved in the highest salinity (35 UPS) and the lowest concentrations of nitrate (4 mmoles L-1). The production of exopolysaccharides was only influenced by salinity, reaching its highest values at 35 UPS (1600 ± 112.25 mg L-1). The content of proteins, lipids, carbohydrates and pigments obtained in this cyanobacterium allow cataloged as an organism which can be used in biotechnology industries, either as feed for farmed organisms or as a source of metabolites of industrial interest. Key words: cyanobacteria, biotechnology, Limnothrix

As cianobactérias são responsáveis pela produção de cianotoxinas que, uma vez acumuladas, podem causar sérios danos à saúde humana e animal. As microcistinas são o tipo mais comum de cianotoxinas e são promotoras de tumores hepáticos. O objetivo deste trabalho foi verificar a ocorrência de cianobactérias e determinar a presença da toxina microcistina em amostras de água do rio Ipojuca no perímetro da cidade de Caruaru, PE, Brasil. Amostras de água foram coletadas em cinco pontos estratégicos deste manancial durante treze meses consecutivos. Para a pesquisa de cianobactérias, foi utilizado o método de sedimentação de Utermöhl para quantificação e identificação das espécies. Para a pesquisa de microcistina foi utilizada a Cromatografia Líquida de Alta Eficiência (CLAE). Os resultados mostraram três gêneros produtores de microcistinas e a presença desta toxina em 100% das amostras analisadas, confirmando a relevância do monitoramento de cianobactérias e cianotoxinas em águas de abastecimento público, pois assim como o rio Ipojuca, vários mananciais de Pernambuco apresentam florações de cianobactérias que podem ser tóxicas. Este trabalho mostrou a importância do estudo destes organismos e a detecção de suas toxinas fornecendo subsídios às ações preventivas de vigilância ambiental em saúde.

As cianobactérias são conhecidamente produtoras de toxinas. Dentro de uma mesma espécie, podemos encontrar variedades tóxicas e não-tóxicas, impossíveis de diferenciação apenas pela morfologia. A principal toxina produzida pelas cianobactérias é a microcistina. Esta proteína é biossintetizada por um grupo de genes conhecidos como mcy. A detecção destes genes a partir de PCR permite a distinção das variedades tóxicas e nãotóxicas. Desse modo, o objetivo desse trabalho foi investigar a ocorrência de florações produtoras de toxinas em um rio tributário do reservatório de Rosana, via amplificação do gene mcyA por PCR. Foram coletadas duas amostras de água da subsuperfície. As duas amostras coletadas no rio do Corvo foram dominadas pela espécie Radiocystis fernandoi e apresentaram resultados positivos para a presença do gene mcyA, confirmando o potencial tóxico dessa espécie. Os resultados representam alerta sobre a qualidade da água do rio do Corvo. A técnica PCR foi eficiente para a rápida detecção de cianobactérias produtoras detoxinas, inclusive podendo ser utilizada antes mesmo do agravamento das condições ambientais pela produção de toxinas, além de apresentar baixo custo.Cyanobacterias are known as toxin producers. Within the same species, toxic and non-toxic varieties can be found and it is impossible to differentiate them only by morphology. The most important toxinproduced by cyanobacteria is microcystin. This protein is synthesized by a cluster of genes known as mcy. The detection of these genes by PCR allows the differentiation of the producing toxin strain from the non-producing toxin strain. Thus, the goal of this work was to investigate the occurrence of toxigenic blooms of cyanobacteria in the Corvo River through PCR amplification of mcyA gene. For this, two samples of blooms of cyanobacteria were collected in Corvo River. Both samples were dominated by Radiocystis fernandoi and presented positive results for the presence of the mcyA gene, which may confirm the potential toxigenicity for that species. These results are an alert about water quality in the Corvo River. Here we demonstrate that amplification of the mcyA gene by PCR is a fast, cheap and efficient method for the detection of toxin- producing cyanobacteria.