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Sample records for alimentado con microalgas

  1. ANALISIS SENSORIAL DE CARNE DE CUYES ALIMENTADOS CON DIETAS SUPLEMENTADAS CON HARINA DE PAJURO (Erithrynaedulis) - UNMSM

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    Guevara, J.; Suca, C.; Suca, F.; Barbachan, H.

    2015-01-01

    El objetivo del estudio fue determinar el análisis sensorial de la carne de cuyes alimentados con dietas suplementadas con diferentes porcentajes de harina de pajuro (Erythrinaedulis). Se llevó a cabo en las instalaciones del galpón de cuyes de la EAP de Ingeniería Agroindustrial de la UNMSM, ubicado en San Juan de Lurigancho.Se empleó un Diseño Completamente al Azar con 3 tratamientos y 3 repeticiones (pozas), considerando3 cuyes por repetición, los cuales fueron distribuidos en forma aleato...

  2. Evaluación del peso de conejos para carne alimentados con diferentes ensilajes

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    Rigoberto Villa-Ramírez

    2016-11-01

    Full Text Available En la Granja Experimental Bengala, de la Universidad del Quindío, ubicada en el municipio de Filandia, Quindío, se evaluó la ganancia de peso en conejos tipo carne cuando son alimentados con diferentes ensilajes: pasto imperial (Axonopus scoparius, pasto imperial mezclado con botón de oro (Tithonia diversifolia (Hemsl., pasto imperial con ramio (Boehmeria nivea y pasto imperial con morera (Morus alba. Se valoraron cuatro tratamientos en cuatro grupos de cinco conejos cada uno. Los conejos alimentados con ensilaje de pasto imperial y botón de oro fueron los que obtuvieron el mayor peso (2389 g, en promedio, mientras que los alimentados con solo forrajes frescos obtuvieron un peso promedio de 2021 g. Las fuentes nutricionales que mejor responden en la alimentación de conejos son, en su orden: ensilaje de botón de oro, ensilaje de morera y ensilaje de ramio.

  3. Carcasas de cabritos alimentados con tres sustitutos lácteos

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    Rebora, Cecilia; Rodríguez, Graciela; Bosch, Silvia van den; Balmes, Luciano; Tacchini, Fabio; Spadoni, Elena; Pedrani, Mirta

    2003-01-01

    Se evaluó y comparó las características de carcasas de cabritos cruza Saanen y Criollo alimentados durante 60 días con tres sustitutos lácteos diferentes: sustituto formulado en la unidad experimental FCA, sustituto comercial para terneros COM y leche de vaca LEC. Se evaluó la aceptación de la carne obtenida por parte del consumidor de Mendoza, Argentina, y la composición acídica de las carcasas. Las div...

  4. Rendimiento de cerdos alimentados con raciones conteniendo subproductos de arroz, durante la fase de crecimiento

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    Victor Hurtado N

    2011-04-01

    Full Text Available Objetivo. Evaluar el rendimiento de cerdos alimentados con raciones conteniendo subproductos de arroz durante la fase de crecimiento. Materiales y métodos. Fueron utilizados 40 lechones mestizos de 31.26 ± 4.62 kg, distribuidos en un diseño experimental de bloques al azar, con los siguientes tratamientos 1. Control, ración basal; 2. Ración con 100% de sustitución de maíz por arroz partido; 3. Ración con 50% de sustitución de maíz por arroz partido; 4. 100% de substitución de maíz por harina de arroz integral y 5. Ración con 50% de substitución de maíz por harina de arroz integral. Resultados. En todas las fases evaluadas (I, II y fase total fue observado un pobre desempeño de los cerdos alimentados con las raciones conteniendo harina de arroz integral, con efectos negativos más evidentes cuando el maíz fue totalmente sustituido por este subproducto (1.467 kg de consumo diario de ración y 0.512 kg de ganancia diaria de peso. La sustitución total o parcial de maíz por arroz partido no afectó el desempeño de los cerdos en crecimiento (1.681 y 1.733 kg de consumo diario de ración y 0.703 y 0.708 kg de ganancia de peso respectivamente. La peor conversión alimenticia (2.87 fue obtenida con la sustitución total del maíz por harina de arroz integral. Conclusiones. El maíz puede ser substituido en 100% en raciones para cerdos en crecimiento por arroz partido y en 50% por harina de arroz integral sin perjudicar La ganancia de peso, el consumo de ración y La conversión alimenticia.

  5. Ganancia de peso de ovinos alimentados con pasto Taiwán (Pennisetum purpureum suplementados con diversas fuentes de proteína

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    R. González-Garduño

    2011-01-01

    Full Text Available El objetivo fue conocer la ganancia diaria de peso (gdp y estimar el consumo de pasto Taiwán en ovinos suplementados con diferentes fuentes de proteína. Se realizaron tres estudios, en el primero, se utilizó pasta de coco (pcoco (Cocus nucifera y pcoco + bloques multinutricionales (bmn que se proporcionaron a siete corderos, respectivamente, en el segundo, se proporcionó un alimento balanceado comercial a un grupo de ocho corderos y se suplementó con pcoco a otros ocho animales, y en el tercero, se suplementó con chícharo Gandul (cgandul (Cajanus cajan a cuatro hembras y cuatro machos y con pcoco a otros dos grupos similares. La investigación se realizó en Salto de Agua, Chiapas, México. Se registró el consumo diario por grupo y cada quince días se registró el peso vivo. El análisis estadístico de gdp se realizó con el procedimiento mixed del sas. Las gdp fueron mayores en el grupo con bmn (0.082± 0.06 kg respecto al sin el bmn (0.045 ± 0.09 kg. La gdp de los corderos alimentados con pcoco fue 0.09 ± 0.02 Kg y los alimentados con pasto Taiwán + pcoco tuvieron 0.06 ± 0.03 Kg. Los corderos machos suplementados con pcoco tuvieron mejor gdp (0.09 ± 0.03 Kg que machos y hembras suplementados con cgandul (0.03 ± 0.02 y 0.04 ± 0.02 Kg, respectivamente. El consumo se incrementó con la edad de los animales y mostró gran variación entre días. La suplementación con pcoco y bmn permiten incrementar las ganancias de peso de corderos estabulados.

  6. Niveles de glucemia en recién nacidos a término, adecuados para la edad gestacional, alimentados con leche materna exclusiva y no exclusiva

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    Custodio Quispe

    2007-06-01

    Full Text Available Introducción: Los recién nacidos (RN alimentados con leche materna exclusiva (LME pueden presentar niveles bajos de glucemia en las primeras horas de su vida y su monitoreo es muy importante. Las hipoglucemias severas están asociadas con secuelas neurológicas. Objetivos: Determinar la influencia de la lactancia materna exclusiva y no exclusiva sobre los niveles de glucemia en el neonato, durante las primeras 24 horas de vida. Diseño: Estudio de tipo cuasiexperimental. Lugar: Servicios de Atención Inmediata y Puericultura, Instituto Nacional Materno Perinatal. Participantes: Recién nacidos. Intervenciones: Se estudió a 90 RN distribuidos en 3 grupos, según modalidades de alimentación: a 30 con LME, b 30 con leche materna más leche maternizada y c 30 con leche materna más suero glucosado. Se captó al RN que reunía los criterios de inclusión y previo consentimiento informado de la madre, se tomó la muestra de sangre a la madre y al neonato, para determinar la glucemia al nacimiento, a las 2, 4, 6, 12, 18 y 24 horas. Principales medidas de resultados: Valores de glucemia en el recién nacido. Resultados: Los RN alimentados con LME tuvieron una tendencia a la disminución de los niveles de glucemia más prolongada y un incremento más tardío del mismo, que los alimentados con leche materna más leche maternizada y leche materna más suero glucosado, siendo estas diferencias altamente significativas (p < 0,0001 y p = 0,006 respectivamente. Conclusiones: El nivel de glucemia menor a 40 mg/dL (hipoglucemia fue mayor en los RN alimentados con LME (16,7%, siguiéndole los alimentados con leche materna más leche maternizada (10% y ninguno en los alimentados con leche materna más suero glucosado. La pérdida ponderal fue mayor en los neonatos alimentados con LME.

  7. Desempeño productivo y rendimiento de canal en pavos alimentados con harina de plumas tratadas con NaOH

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    Enrique Loyra T.

    2013-08-01

    Full Text Available Objetivo. Evaluar el desempeño productivo y el rendimiento de la canal en pavos en crecimiento alimentados con dietas elaboradas con harina de plumas (HP. Materiales y métodos. Los tratamientos fueron una dieta control y dos dietas experimentales con harina de plumas tratada con 50 ó 100 g de NaOH/kg. Se utilizó un diseño de bloques al azar. El consumo de alimento y el peso de los animales se registró cada dos semanas. Los datos del desempeño productivo se analizaron con el procedimiento MIXED del programa estadístico SAS. El rendimiento de la canal se analizó con el procedimiento GLM del programa estadístico SAS. Resultados. Los pavos que consumieron la dieta testigo tuvieron mejores ganancias de peso (GP, consumo de alimento (CA, peso de la canal y de sus partes (p<0.05 que aquellas con harina de plumas. Sin embargo, se observó una mayor GP, CA, peso de la canal y del muslo (p<0.05 cuando se trató la harina de plumas con 100 g de NaOH/kg. Conclusiones. Los resultados obtenidos indican que la utilización de harina de plumas disminuyó el comportamiento productivo y el rendimiento de canal en los pavos. Sin embargo, el aumento del tratamiento de la harina de plumas de 50 a 100 g de NaOH/kg mejoró el comportamiento productivo y el rendimiento de canal.

  8. Respuesta productiva de conejos alimentados con forraje verde hidropónico de avena, como reemplazo parcial de concentrado comercial

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    Francisco Fabián Fuentes Carmona

    2011-04-01

    Full Text Available La respuesta productiva de conejos raza californiana alimentados con forraje verde hidropónico (FVH de avena como reemplazo parcial de concentrado comercial (CC, fue evaluada en condiciones de desierto en el norte de Chile. Se establecieron cinco tratamientos de alimentación, equivalentes a 0, 25, 50, 75 y 100% de reemplazo de la dieta diaria con FVH, el cual fue cosechado y utilizado directamente diez días después de la siembra. Cuarenta y cinco conejos destetados a los 31 días fueron evaluados en un diseño completamente al azar hasta alcanzar un peso de sacrificio de 2 kg de peso vivo. La calidad del FVH de avena fue considerada como buena, presentando similar valor nutritivo que el CC. Las variables evaluadas y sus respectivos rangos fueron: consumo de materia seca promedio (59.17 - 104.73 g/día, ganancia de peso vivo promedio (16.35 - 29.10 g/animal por día, conversión alimenticia promedio (3.31 - 3.93 kg MS/kg PV, tiempo de peso vivo a sacrificio (53 - 91 días, peso vivo final (1430 - 2044 g/animal, peso de la canal (1235 - 1385 g/animal y rendimiento de la canal (59.19 - 62.25%. El reemplazo de hasta 50% de la dieta base con FVH de avena no afectó significativamente (P < 0.05 el consumo de alimento, tiempo de peso vivo a sacrificio, peso vivo final y rendimiento de la canal, haciendo posible su uso como recurso forrajero alternativo en la alimentación de conejos en etapa de engorde en condiciones de desierto.

  9. Respuesta productiva de conejos alimentados con forraje verde hidropónico de avena, como reemplazo parcial de concentrado comercial

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    Poblete Pérez Cecilia Eva

    2011-06-01

    Full Text Available La respuesta productiva de conejos raza californiana alimentados con forraje verde hidropónico (FVH deavena como reemplazo parcial de concentrado comercial (CC, fue evaluada en condiciones de desiertoen el norte de Chile. Se establecieron cinco tratamientos de alimentación, equivalentes a 0, 25, 50, 75 y100% de reemplazo de la dieta diaria con FVH, el cual fue cosechado y utilizado directamente diez díasdespués de la siembra. Cuarenta y cinco conejos destetados a los 31 días fueron evaluados en un diseñocompletamente al azar hasta alcanzar un peso de sacrificio de 2 kg de peso vivo. La calidad del FVH deavena fue considerada como buena, presentando similar valor nutritivo que el CC. Las variables evaluadasy sus respectivos rangos fueron: consumo de materia seca promedio (59.17 - 104.73 g/día, gananciade peso vivo promedio (16.35 - 29.10 g/animal por día, conversión alimenticia promedio (3.31 - 3.93 kgMS/kg PV, tiempo de peso vivo a sacrificio (53 - 91 días, peso vivo final (1430 - 2044 g/animal, pesode la canal (1235 - 1385 g/animal y rendimiento de la canal (59.19 - 62.25%. El reemplazo de hasta50% de la dieta base con FVH de avena no afectó significativamente (P ≤ 0.05 el consumo de alimento,tiempo de peso vivo a sacrificio, peso vivo final y rendimiento de la canal, haciendo posible su uso comorecurso forrajero alternativo en la alimentación de conejos en etapa de engorde en condiciones de desierto.

  10. Cultivo de microalgas (Chlorella sorokiniana) con iluminación mediante LEDs

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    Plasencia Álvarez, Juan

    2012-01-01

    Con el fin de establecer si es posible llevar a cabo el cultivo de microalgas empleando LEDs (Light Emitting Diodes) y si el empleo de los mismos supone alguna ventaja, se llevaron a cabo cinco experiencias con el microalga Chlorella sorokiniana en las que se varió la cantidad y la calidad de la luz aplicada. En las dos primeras experiencias se empleó luz de un solo color, roja en la primera y azul en la segunda, ambas al 50 % de su intensidad. En las tres siguiente se ensayaron mezclas de am...

  11. Emisión de metano en ovinos alimentados con Pennisetum purpureum y árboles que contienen taninos condensados

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    Angel Piñeiro-Vázquez

    2017-04-01

    Full Text Available El objetivo fue evaluar el efecto de los taninos condensados (TC contenidos en el follaje de arbóreas tropicales, sobre el consumo de materia seca y orgánica (CMS, CMO, la digestibilidad de la materia seca (DMS y emisiones de metano (CH4 en ovinos alimentados con una ración basal de pasto Pennisetum purpureum. Cuatro ovinos de pelo con un peso vivo promedio de 21.6±2.0 kg se sometieron a cuatro tratamientos en un diseño cuadro latino 4 x 4. Los tratamientos fueron P. purpureum (PP, P. purpureum + Havardia albicans (PPHA, P. purpureum + Bursera simaruba (PPBS, y P. purpureum + Acacia pennatula (PPAP; el follaje de las arbóreas se incluyó en 300 g/kg de MS de la ración. El consumo, la digestibilidad y la producción total de metano entérico se midieron por periodos de 23 h. La producción de metano se midió en cajas de respiración de circuito abierto. El consumo y digestibilidad de la MS y materia orgánica (MO entre los tratamientos PP, PPHA, PPBS y PPAP no se afectaron por la inclusión de los follajes de arbóreas en la ración (P>0.05. Cuando la producción de CH4 se expresó en L/kg del CMS, CMO o consumo de fibra detergente neutro los resultados fueron similares entre tratamientos (PP, PPHA, PPBS y PPAP (P>0.05. Se concluye que los TC contenidos en el follaje de Havardia albicans, Acacia pennatula y Bursera simaruba no afectaron las emisiones de CH4 al nivel de incorporación de 30 % de la MS; tampoco se observaron efectos en el CMS, CMO, DMS y concentración molar de ácidos grasos volátiles.

  12. CULTIVO EXPERIMENTAL DEL CLADOCERO Moina sp ALIMENTADO CON Ankistrodesmus sp y Saccharomyces cereviseae

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    Martha Prieto

    2006-05-01

    Full Text Available Saccharomyces cereviseae. Materiales y métodos. Fueron realizados cultivos experimentales de la cepade cladóceros Moina sp en el laboratorio de Alimento Vivo de la Universidad de Córdoba, bajo condicionescontroladas de temperatura (22oC, pH (7.6, intensidad lumínica (2000 lux y aireación. Se emplearondos dietas de alimento como tratamiento (Ankistrodesmus y Ankistrodesmus mas Saccharomyces cereviseaeen concentración de 40 x 105 cel.ml-1 cada uno, para determinar su efecto sobre el desempeño de lapoblación. Diariamente se registró la densidad poblacional y celular. Resultados. Se obtuvieron diferenciassignificativas para el efecto de las dietas sobre el crecimiento poblacional de los cladóceros, los individuosalimentados con Ankistrodesmus sp + Saccharomyces cereviseae alcanzaron una densidad de 12.3a±0.30 org/ml-1 presentando mayor tasa instantánea de crecimiento (K 0.36 ± 0.002, el menor tiempode duplicación (td 1.94 ± 0.012 y el mayor rendimiento (r 1,1 ± 0.07 clad.ml-1.día-1. Conclusión. Loscladóceros por sus características de crecimiento en cultivo, presentan adaptación favorable a lascondiciones de manejo para la producción de biomasas potencialmente útiles como partícula nutritivacon fines acuícolas.

  13. Crecimiento de niños amamantados y alimentados con biberón hasta los 2 años de vida: estudio CLACYD, 1993-1995

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    Agrelo Fernando

    1999-01-01

    Full Text Available Los estudios realizados en distintos países muestran diferencias importantes en el crecimiento de niños amamantados y alimentados con biberón; también se ha observado que los niños amamantados crecen más despacio a partir de los 2 ó 3 meses de edad, en comparación con el patrón de referencia NCHS/OMS (National Center for Health Statistics/Organización Mundial de la Salud. Estos resultados ponen en tela de juicio la equivalencia entre el crecimiento máximo y el óptimo. El presente trabajo tuvo como objetivo comparar el crecimiento en peso y longitud desde el nacimiento hasta los 24 meses, de un grupo de niños amamantado y otro alimentado con biberón, y describir el crecimiento del grupo de amamantados en relación con las normas NCHS/OMS y con el "conjunto mixto de datos de la OMS sobre niños amamantados" conocido como el 12-month breast-fed pooled data set. Con ese fin se analizaron datos procedentes del estudio Córdoba: lactancia, alimentación, crecimiento y desarrollo (CLACYD, en el cual se investigó a una cohorte representativa, estratificada por nivel social, de niños nacidos en 1993 en la ciudad de Córdoba, Argentina. Se analizaron los datos antropométricos de 74 niños amamantados durante el primer año de vida y 108 niños alimentados con biberón, que se registraron según técnicas estandarizadas al nacer y a los 6, 12 y 24 meses de edad. Los dos grupos eran homogéneos con respecto a la edad y la escolaridad de los padres, el estrato social, el orden de nacimiento, la talla materna, y el peso y la longitud al nacer. Las condiciones de vida (vivienda y saneamiento eran más favorables en el grupo con alimentación artificial (P = 0,04. Los niños amamantados registraron menor peso y longitud a los 6, 12 y 24 meses que los alimentados con biberón y mostraron, con respecto a las pautas NCHS/OMS, una desaceleración del crecimiento a partir del segundo semestre, lo cual indica que las normas NCHS/OMS no son del todo

  14. Lípidos sanguíneos en cerdos alimentados con pijiguao (Bactris gasipaes Kunth y lisina sintética

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    Janeth Colina R.

    2011-12-01

    Full Text Available Objetivo. Evaluar el efecto de la harina de pijiguao y lisina sintética sobre los lípidos sanguíneos de cerdos en crecimiento y engorde. Materiales y métodos. El estudio se realizó en dos etapas. En la primera etapa se utilizaron 72 cerdos castrados en crecimientode 30 ± 0.5 kg, en un arreglo factorial 2x3: dos niveles de lisina sintética (0 y 2.70 g/kgy tres niveles de harina de pijiguao (0, 160 y 320 g/kg. En la segunda etapa se utilizaron 16 cerdos en engorde de 67.25 ± 1.17 kg, en un arreglo factorial 2x2: dos niveles de lisinasintética (0 y 2.70 g/kg y dos niveles de pijiguao (0 y 175 g/kg. Se determinaron las concentraciones séricas de triacilgliceroles, colesterol total y ácidos grasos. Resultados. Los cerdos en crecimiento que consumieron pijiguao presentaron menores (p<0.001concentraciones de colesterol que el grupo control (2.27 y 2.23 mmol/l vs 2.56 mmol/l y triacilgliceroles (0.34 y 0.28 mmol/l vs 0.42 mmol/l. El ácido oleico incrementó (p<0.01con el mayor nivel de pijiguao (20.78% a 28.84%, y la lisina aumentó (p<0.05 el ácidolinoleico (27.83% a 31.29%. Los cerdos alimentados con pijiguao y lisina mostraron menor (p<0.001 ácido palmítico que el grupo con pijiguao sin lisina (0.23 y 0.19% vs 0.45 y 0.62%, respectivamente. En la etapa de engorde los triacilgliceroles disminuyeron (p<0.05 en los cerdos alimentados con pijiguao y lisina (0.46 a 0.36 mmol/l. Los cerdos alimentados con pijiguao mostraron menor ácido linoleico y mayor ácido oleico (p<0.001. Conclusiones. Las dietas con pijiguao y lisina sintética no causaron efectos negativos sobre los lípidos sanguíneos de cerdos.

  15. An integral term adaptive neural control of fed-batch fermentation biotechnological process; Control neuronal adaptable con termino integral para un proceso biotecnologico de fermentacion por lote alimentado

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    Baruch, Ieroham; Hernandez, Luis Alberto; Barrera Cortes, Josefina [Centro de Investigacion y de Estudios Avanzados, Instituto Politecnico Nacional, Mexico D.F. (Mexico)

    2005-07-15

    A nonlinear mathematical model of aerobic biotechnological process of a fed-batch fermentation system is derived using ordinary differential equations. A neurocontrol is applied using Recurrent Trainable Neural Network (RTNN) plus integral term; the first network performs an approximation of the plant's output; the second network generates the control signal so that the biomass concentration could be regulated by the nutrient influent flow rate into the bioreactor. [Spanish] Un modelo matematico no lineal de un proceso biotecnologico aerobio de un sistema de fermentacion por lote alimentado es presentado mediante ecuaciones diferenciales ordinarias. Es propuesto un control utilizando dos redes neuronales recurrentes entrenables (RNRE) con la adicion de un termino integral; la primera red representa un aproximador de la salida de la planta y la segunda genera la senal de control tal que la concentracion de la biomasa pueda ser regulada mediante la alimentacion de un flujo con nutrientes al biorreactor.

  16. Dinámica poblacional del rotífero Brachionus ibericus aislado de estanques para camarón, alimentado con diferentes dietas

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    José Cristóbal Román-Reyes

    2014-11-01

    Full Text Available La producción de microalgas vivas para cultivar rotíferos constituye uno de los mayores costos de operación en la larvicultura de peces, por lo que se están desarrollando sustitutos comerciales de microalgas para la alimentación y producción de rotíferos. Se desconoce el efecto que tienen las formulaciones comerciales sobre la dinámica poblacional de rotíferos nativos del noroeste de México y en este estudio se evaluó el efecto de cuatro dietas comerciales (Espirulina, RotiMac®, Nanno 3600®, RotiGrow-Plus® y la microalga viva Nannochloropsis sp., sobre el crecimiento poblacional y fecundidad del rotífero Brachionus ibericus (GenBank KJ949043, aislado de una granja de camarón blanco (Litopenaeus vannamei. Se realizaron cinco réplicas por tratamiento alimenticio utilizando recipientes con volumen de 12 L de agua, con temperatura de 29 ± 1°C y salinidad de 35 ± 1, respectivamente. Los resultados mostraron que durante los periodos experimentales, las dietas probadas resultaron adecuadas para alimentar a B. ibericus, con tasas de crecimiento, tiempos de duplicación, densidades máximas y fecundidades que fluctuaron entre 0.20 a 0.27 rotíferos día-1, 2.60 a 3.42 días, 215 a 344 rotíferos mL-1 y de 0.16 a 0.39 huevos hembra-1, respectivamente. Las diferencias entre tratamientos fueron significativas (P 0.05 a las obtenidas con Nanno 3600®.

  17. Effect of alternative mediums on production and proximate composition of the microalgae Chaetoceros muelleri as food in culture of the copepod Acartia sp. Efecto de medios alternativos sobre la producción y composición proximal de la microalga Chaetoceros muelleri como alimento en cultivo del copépodo Acartia sp.

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    Luis R Martínez-Córdova

    2012-03-01

    . La biomasa y concentración celular finales también fueron más altas en Agr-F. Las microalgas de Agr-F y Aq-F tuvieron mayor contenido de carbohidratos y menor contenido de proteína en comparación con el control. No se observaron diferencias en los contenidos de lípidos y cenizas. Respecto a la producción de copépodos, las mayores densidades e índices de fecundidad se observaron en los organismos alimentados con microalgas producidas en Agr-F y Aq-F, en comparación con el control. La proporción adulto-nauplio también fue mayor en copépodos alimentados con microalga de Agr-F comparada con Aq-F y el control. Los copépodos alimentados con microalgas del Agr-F y Aq-F, tuvieron un mayor contenido de proteínas que el control; la cantidad de carbohidratos fue mayor en copépodos alimentados con microalga del Agr-F comparada con Aq-F. No se observaron diferencias en los contenidos de lípidos y cenizas. Agr-F y Aq-F fueron medios alternativos adecuados para producir C. muelleri, los cuales produjeron microalgas de alta calidad que incrementaron la producción de copépodos.

  18. Productividad y eficiencia de uso de nitrógeno y energía en pollos de engorda alimentados con pasta de soya o pasta de canola

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    Sergio Gómez Rosales

    2012-01-01

    Full Text Available Se realizaron dos experimentos de sacrificio para evaluar el crecimiento, contenido y deposición de tejidos y retención de proteína y energía en la carne de la canal en pollos en crecimiento alimentados con pasta de canola (PCAN en sustitución de pasta de soya (PSOY. En el Exp 1, seis pollos machos, de 43 días de edad, se sacrificaron al inicio y 36 pollos fueron asignados a tres dietas con cantidades crecientes de PCAN (0, 10 y 20 % combinadas con dos niveles de lisina digestible (LD: 0.85 y 0.95 %. En el Exp 2, seis hembras y seis machos, de 28 días de edad, se sacrificaron al inicio y 72 pollos fueron asignados, por sexo, a dos dietas (PSOY o PCAN como único ingrediente proteico combinadas con tres niveles de energía (3.0, 3.1 y 3.2 Mcal de EM/kg de alimento. Cada experimento duró dos semanas y al final todos los pollos fueron sacrificados. En el Exp 1, no hubo diferencias estadísticas en la productividad o retención de proteína y energía en la canal entre niveles de PCAN (P>0.05. En el Exp 2, el consumo de alimento, proteína y energía y la deposición de grasa fueron mayores (P<0.05 con PSOY, pero la ganancia de peso, eficiencia alimenticia y retención de proteína y energía en la canal fueron similares entre dietas. Los resultados indican que es factible sustituir parcial o totalmente la pasta de soya por pasta de canola en la dieta de pollos de engorda en crecimiento.

  19. Utilización de la proteína dietaría por alevinos de la gamitana, Colossoma macropomum, alimentados con dietas isocalóricas

    Directory of Open Access Journals (Sweden)

    Félix Walter Gutiérrez

    2011-05-01

    Full Text Available Un experimento fue conducido para evaluar los efectos de cinco niveles de proteína (25,27, 29, 31 y 33% sobre el comportamiento productivo de alevinos de la gamitana, Colossoma macropomum Cuvier 1818, alimentados con dietas isocalóricas (2,7 kcal de ED/g. Los parámetros medidos fueron ganancia de peso (GP, conversión alimenticia (CA, proteína retenida (PR, razón de eficiencia proteica (REP y energía retenida (ER. En la preparación de las dietas experimentales se utilizaron como fuentes de proteína harina de anchoveta y harina de torta de soya y como fuentes de energía maíz amarillo duro, subproducto de trigo y aceite de pescado. Se encontraron diferencias significativas (P<0,05 entre tratamientos para los parámetros GP, PR, REP y ER. No se encontraron diferencias significativas para la CA. Los mejores rendimientos fueron obtenidos cuando las gamitanas fueron alimentadas con niveles dietarios de 25, 27 y 33% de proteína cruda. También se encontró que a medida que se elevó el nivel de proteína de la dieta, la REP decreció significativamente. Tomando en cuenta el costo de la proteína en la dieta, se concluye que la alimentación de la gamitana con niveles dietarios de 25 ó 27% de proteína cruda y 2,7 kcal de ED/g, garantizarán su exitoso crecimiento.

  20. Alimentación y defecación en triatominos del género Rhodnius (Hemiptera: Reduviidae alimentados con sangre humana

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    E. Aldana

    2001-06-01

    Full Text Available Se estudió el comportamiento alimenticio y de defecación de Rhodnius prolixus Stal, 1859, R. robustus Larrousse, 1927, R. neivai Lent, 1953 y R. pictipes Stal, 1872 alimentados artificialmente con sangre humana en condiciones de laboratorio. La ninfa I de todas las especies no defecaron en la primera media hora después de haber iniciado la ingesta. R. pictipes no se acercó a picar en el alimentador artificial aunque si lo hizo cuando el alimento se ofreció directamente sobre el cuerpo humano. Las ninfas y adultos de R. prolixus mostraron índices de defecación (ID superiores a los correspondientes de las otras especies, y la ninfa III presentó el mayor ID=1.62. La mayoría de individuos de todos los estadíos de desarrollo aceptaron el alimento en un tiempo entre 0 y 3 min y se alimentaron en menos de 15 minutos.Feeding and defecaction behavior of Rhodnius prolixus Stal, 1859, R. robustus Larrousse, 1927, R. neivai Lent, 1953 and R. pictipes Stal, 1872, artificially fed on human blood, were studied under laboratory conditions. In all species, first instar nymphs did not defecate in the first 30 minutes after feeding. R. pictipes did not accept artificial feeding but fed directly on humans. Nymph and adult R. prolixus had a higher defecation index (DI than other species; third instar nymphs had the highest DI=1.62. In all instars, most individuals accepted the food in £ 3 minutes and finished feeding in less than 15 minutes.

  1. Diseño y simulación de un balastro electrónico con corrección de factor de potencia con topología buck-boost e inversor alimentado por corriente

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    Germán E. Melo

    2014-08-01

    Full Text Available Las lámparas fluorescentes compactas o CFL (compact fluorescent lamp se han convertido en uno de los tipos de iluminación más usados en la actualidad. Sin embargo, las CFL comerciales poseen en su mayoría balastros electrónicos de bajo factor de potencia. Esto genera un aumento en los niveles de distorsión del sistema de generación y distribución debido al uso masivo de estas lámparas. En el presente artículo se presenta el diseño y simulación de un balastro electrónico con corrección de factor de potencia para lámparas fluorescentes compactas. La propuesta busca evaluar la viabilidad de integrar el correcto funcionamiento, tamaño y costo de este dispositivo. La topología propuesta es una etapa buck-boost operando en modo de conducción discontinua integrada a un inversor alimentado por corriente. La alta factibilidad de implementación de esta topología es mostrada mediante simulaciones que logran un factor de potencia de 0.998 y una distorsión total armónica menor de 5 %.

  2. Diseño y simulación de un balastro electrónico con corrección de factor de potencia con topología buck-boost e inversor alimentado por corriente

    Directory of Open Access Journals (Sweden)

    Germán E. Melo

    2014-05-01

    Full Text Available Las lámparas fluorescentes compactas o CFL (compact fluorescent lamp se han convertido en uno de los tipos de iluminación más usados en la actualidad. Sin embargo, las CFL comerciales poseen en su mayoría balastros electrónicos de bajo factor de potencia. Esto genera un aumento en los niveles de distorsión del sistema de generación y distribución debido al uso masivo de estas lámparas. En el presente artículo se presenta el diseño y simulación de un balastro electrónico con corrección de factor de potencia para lámparas fluorescentes compactas. La propuesta busca evaluar la viabilidad de integrar el correcto funcionamiento, tamaño y costo de este dispositivo. La topología propuesta es una etapa buck-boost operando en modo de conducción discontinua integrada a un inversor alimentado por corriente. La alta factibilidad de implementación de esta topología es mostrada mediante simulaciones que logran un factor de potencia de 0.998 y una distorsión total armónica menor de 5 %.

  3. Metabolitos sanguíneos en caprinos alimentados con mezclas integrales frescas con Moringa oleífera: Pennisetum purpureum Clon-OM22

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    Nelson Norberto González González

    2015-01-01

    Full Text Available Se evaluó el comportamiento de metabolitos sanguíneos energéticos y proteicos con el uso de mezclas de Moringa oleífera : Pennisetum purpureum clon OM-22. Se utilizaron cuatro machos caprinos de raza Alpina, con 37.78 ±4.87 kg de peso vivo, dos años de edad y alojados en jaulas metabólicas individuales, or - ganizados en un diseño cuadrado latino (4x4. El tiempo experimental fue 60 días, con cuatro periodos de 15 días. Los tratamientos consistie - ron en la inclusión creciente de Moringa oleífera (MO20%, MO40%, MO80% en sustitución de Pennisetum purpureum clon OM-22 (20:80, 40:60; 80:20% en la mezcla integral y un testigo, al que se le ofertó concentrado comer - cial (6g kg PV -1 . La totalidad de los forrajes frescos fueron cosechados, molidos (3-5cm y mezclados, ofertados a razón del 3% del peso vivo base seca, en dos ocasiones (10:30-16:30 horas durante el día. El estado de los metaboli - tos sanguíneo fue evaluado 22 horas posteriores al consumo de alimento. Las concentraciones de Glucosa, Colesterol, Triglicéridos y Urea se mantuvieron dentro del rango fisiológico. Los valores de Urea y Colesterol mostraron una ten - dencia creciente con la moringa en la mezcla, a diferencia de los Triglicéridos, que disminu - yeron. Los niveles de Creatinina en MO40 y MO80% superaron el límite fisiológico para la especie (59.7-134.8 μmol/l, indicando un posible fallo renal. Estos resultados permiten concluir que la Moringa oleífera con un nivel de inclusión del 20% constituye una alternativa alimentaria para caprinos; pero requiere de es - tudios para dilucidar niveles de Creatinina con la inclusión de 40 y 80% moringa.

  4. Sobrevivencia, metamorfosis y crecimiento de larvas del camarón Penaeus californiensis (Decapoda: Peneidae alimentadas con diferentes microalgas

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    José Naranjo

    1999-12-01

    Full Text Available Se realizó una prueba experimental en un Centro de Producción Ostrícola en Bahía de Kino, Sonora, con el fin de evaluar el efecto de diferentes microalgas en el desarrollo de larvas de camarón café Penaeus californiensis. Las microalgas evaluadas fueron la diatomea Chaetoceros gracilis y los fitoflagelados Isochrysis galbana y Dunalliella sp., solas o en combinación y adición de nauplios de Artemia sp. a partir del estadio de zoea III, excepto en un tratamiento donde no se adicionó Artemia sp. Se utilizaron 24 unidades experimentales (tres por tratamiento, consistentes en garrafones plásticos de 16 l de capacidad, una densidad de siembra de 50 nauplios/l, una temperatura de 25°C controlada mediante calentadores sumergibles de 50 watts y una salinidad de 35 ppmil. C. gracilis produjo la mejor sobrevivencia (55%, siguiendole la combinación de C. gracilis con Dunaliella sp. (48%, la más baja sobrevivencia fue para el tratamiento donde se utilizó Dunaliella sp. fueron evidentes un retraso en la velocidad de metamorfosis para los tratamientos donde C. gracilis no fue utilizada y diferencias significativas (pThe effect of three microalgae, Chaetoceros gracilis, Isochrysis galbana, and Dunalliella sp. on the larval development of yellowleg shrimp Penaeus californiensis, was evaluated in the Oyster Production Center of Bahia Kino, Sonora, México. The effects of each microalgae (1 individually, (2 combined and (3 mixed with Artemia nauplii (from zoea III stage, were considered. Twenty four experimental units (three 16.0 l plastic bottles per treatment were used. During the experiment temperature was maintained around 25°C, and salinity around 35 ppt. The stocking density of nauplii was 50/l. The best survival was obtained with C. gracilis (55%, followed by the combination of C. gracilis and Dunalliella sp (48%. The worst survival was obtained in the treatment with Dunalliella sp. An evident delay in the metamorphosis times was observed in

  5. Monster potential meets potential monster: pros and cons of deploying genetically modified microalgae for biofuels production.

    Science.gov (United States)

    Flynn, K J; Mitra, A; Greenwell, H C; Sui, J

    2013-02-06

    Biofuels production from microalgae attracts much attention but remains an unproven technology. We explore routes to enhance production through modifications to a range of generic microalgal physiological characteristics. Our analysis shows that biofuels production may be enhanced ca fivefold through genetic modification (GM) of factors affecting growth rate, respiration, photoacclimation, photosynthesis efficiency and the minimum cell quotas for nitrogen and phosphorous (N : C and P : C). However, simulations indicate that the ideal GM microalgae for commercial deployment could, on escape to the environment, become a harmful algal bloom species par excellence, with attendant risks to ecosystems and livelihoods. In large measure, this is because an organism able to produce carbohydrate and/or lipid at high rates, providing stock metabolites for biofuels production, will also be able to attain a stoichiometric composition that will be far from optimal as food for the support of zooplankton growth. This composition could suppress or even halt the grazing activity that would otherwise control the microalgal growth in nature. In consequence, we recommend that the genetic manipulation of microalgae, with inherent consequences on a scale comparable to geoengineering, should be considered under strict international regulation.

  6. Evaluación del crecimiento del pulpo común Octopus mimus del norte de Chile alimentado con dietas formuladas Growth evaluation of octopus (Octopus mimus from northern Chile fed with formulated diets

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    Oscar Zúñiga

    2011-11-01

    Full Text Available Durante 57 días se comparó el crecimiento y sobreviviencia de pulpos juveniles Octopus mimus del norte de Chile alimentados con tres diferentes dietas: dos dietas húmedas (A y B aglutinadas con solución de gelatina embutidas en tripa de cordero y una dieta control (C natural. La dieta (A fue elaborada en base a una mezcla de filete triturado del pescado Cheilodactylus variegatus con harina de pellet para salmón, la dieta (B con pasta de almeja (Protothaca thaca mezclada con filete de Ch. variegatus y la dieta control consistió en el suministro de almejas frescas congeladas (C. Basado en un diseño experimental de medidas repetidas, los pulpos se mantuvieron individualmente en estanques de 70 L con circulación de agua de mar y aireación permanente. Los pulpos que consumieron la dieta B no experimentaron mortalidad y la dieta control C presentó mortalidad del 16,7%, sus crecimiento fueron similares (P > 0,05 con tasas de crecimiento absoluta (AGR de 7,0 ± 0,91 (g d-1 y 6,6 ± 1,10 (g d-1 respectivamente. Los pulpos alimentados con la dieta A registraron mortalidad de 33,3% y tasa de crecimiento absoluta negativa, AGR= -1,70 ± 0,37 (g d-1. La dieta A que contenía como ingrediente pellet para salmón molido como harina no tuvo una adecuada aceptación y los ejemplares experimentaron disminución de su peso. La dieta B preparada con gelatina de origen animal como aglutinante, no implicó un efecto negativo en la palatabilidad y aceptabilidad en comparación al control basada en almeja fresca congelada, incluso los organismos lograron crecimientos similares. Los resultados permitirán a futuro mejorar la calidad nutricional de dietas artificiales para maximizar el crecimiento de O. mimus en cautiverio.The growth and survival of juvenile octopus, Octopus mimus, from northern Chile, fed three different diets were analyze during 57 days. Two of the diets (A and B were wet diets stuffed in lamb gut with a gelatin solution, and the third (C was

  7. Evaluación de la estructura espacial de Triatoma maculata del centro-occidente de Venezuela y su viabilidad alimentado con sangre humana en condiciones de laboratorio

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    Keila Torres

    2010-03-01

    Conclusiones. T. maculata de la localidad de Xaguas podría encontrarse en un estado de adaptación al domicilio con fuentes sanguíneas diferentes al humano y en un estado incipiente de adaptación al domicilio con la sangre humana como fuente de alimentación.

  8. Balance de nitrógeno, emisión de amonio y olores de cerdos alimentados con dietas bajas en proteína

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    Harold Anindo Rachuonyo

    2015-01-01

    Full Text Available El efecto de reducir el nivel de proteína cruda (PC en la dieta de cerdos en crecimiento se evaluó en dos estudios, usando dietas formuladas para un nivel normal (19% o reducido (14% de PC, manteniendo constante la lisina ileal digestible estandarizada (0.85% y energía (3.37 Mcal ME/kg. El estudio I midió el balance de N en 24 cerdos con peso inicial de 17.7±1.29 kg, mientras que el estudio II usó 24 cerdos con peso inicial de 17.9±0.76 kg, para medir las emisiones aéreas de NH3 y los niveles de olor en cámaras con flujo de aire dinámico por 21 días. En el estudio I, el N consumido (26.6 %, urinario (56 % y su excreción total (41 % se redujeron (P0.4. En el estudio II, reducir la PC no afectó (P>0.10 el comportamiento productivo, pero tendió a reducir (P<0.10 el pH de los purines (6.71, normal a 6.21±0.186 PC reducida y las emisiones de NH3 luego del día 9 (interacción dieta y día de estudio, P<0.001. El olor en muestras tomadas a 14 y 21 días, no difirió (512 y 540±115.6 diluciones al umbral de olor, para PC reducida y normal, pero sí aumentó (P<0.01 con el tiempo de alimentación (440 y 612±111.3 diluciones a 14 y 21 días. Los resultados sugieren que por cada unidad porcentual de reducción en la PC se reduce la excreción de N (8 % y las emisiones de NH3 en purines (15 %, sin cambiar la intensidad del olor.

  9. Características de la canal, rendimiento en cortes primarios y composición tisular de corderos Katahdin x Pelibuey alimentados con garbanzo de desecho

    Directory of Open Access Journals (Sweden)

    Francisco Gerardo Ríos Rincón

    2012-01-01

    Full Text Available Para determinar el efecto de la inclusión de 0, 15, 30, 45 ó 60 % de garbanzo de desecho (GD en las características de la canal, rendimiento en cortes primarios y composición tisular, se utilizaron 40 canales de corderos Katahdin x Pelibuey. Se registraron las características de la canal y los cortes primarios se diseccionaron en tejido magro (TM, adiposo (TA y óseo (TO. La inclusión de GD no modificó (P>0.05 la respuesta productiva ni las características de la canal, mientras que la grasa pélvico-renal incrementó en los tratamientos con 45 y 60 % (P0.05 en el rendimiento de cuello, hombro, brazuelo, pecho y lomo, a diferencia del costillar y la falda, donde éste fue inferior (P<0.05 en los corderos que recibieron GD. En respuesta a la inclusión de GD, aumentó (P<0.05 el TA de pierna (9.9 vs 13.1 %, pecho (16.1 vs 26.0 %, brazuelo (13.2 vs 18.2 % y falda (43.6 vs 51.2 %; y disminuyó (P<0.02 el TM en pecho (66.8 vs 57.7 % y falda (56.4 vs 48.8 %. El TM total disminuyó (62.6 vs 58.0 %; P<0.04; y el TA total incrementó con la inclusión de GD (17.1 vs 21.5 %; P<0.02. La relación músculo/grasa se modificó (P<0.02 por la inclusión de GD (3.7 vs 2.8. Se concluye que la inclusión de más de 45 % de garbanzo de desecho en la dieta reduce la proporción de tejido magro e incrementa el adiposo en las canales de corderos Katahdin x Pelibuey en finalización intensiva.

  10. Fatty Acid Composition of Longissimus dorsi Muscle of Suffolk Down Lambs Fed on Different Dryland Forages Composición de Ácidos Grasos del Músculo Longissimus dorsi de Corderos Suffolk Down Alimentados con Diferentes Forrajes

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    María Asunción Gallardo

    2011-12-01

    , poliinsaturados (PUFA, y razón omega 6/omega 3 (06/03. Hubo una tendencia (p > 0,06 hacia un mayor contenido de ácidos grasos monoinsaturados (MUFA en la carne de corderos alimentados con trébol rosado, comparado con los otros tipos de praderas. Aunque no hubo diferencias significativas entre tratamientos, los resultados obtenidos con la pradera sucesional no pueden ser extrapolados a pasturas naturales en el secano, debido a sus altos contenidos de leguminosas. Se concluye que el uso de trébol subterráneo proveería una similar calidad de carne, al comparar con forrajes basados en trébol rosado.

  11. Microbial protein synthesis in young steers fed with grass silage and extruded corn Síntesis de proteína microbiana en novillos jóvenes alimentados con ensilaje de praderas y maíz extruido

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    Claudia Barchiesi-Ferrari

    2012-12-01

    Full Text Available Microbial protein synthesis is essential to meet protein requirements in ruminants. The aim of this investigation was to evaluate the effect of incorporating extruded corn (Zea mays L. into the ration of young steers fed with grass silage on microbial protein synthesis (MPS. Twenty young steers in metabolic cages were used for supplying food. The treatments consisted of combinations of extruded corn (EC and ground corn (GC EC-10 (10% EC-30% GC; EC-25 (25% EC-15% GC and EC-40 (40% EC-0% GC. These foods constituted 40% of the ration (DM-based and the remaining 60% was grass silage. The MPS was calculated through the excretion of purine derivatives (PD in the urine, using total collection of urine. The inclusion of a higher percentage of extruded corn (EC-40 increased the PD excretion (51.85 mmol d-1, P La síntesis de proteína microbiana es fundamental para satisfacer los requerimientos proteicos en rumiantes. El objetivo de esta investigation fue evaluar el efecto de incluir maíz (Zea mays L. extruido en la ración de novillos alimentados con ensilaje de pradera, sobre la sintesis de proteina microbiana (MPS. Se emplearon 20 novillos jóvenes ubicados en jaulas metabólicas para suministro de los alimentos. Los tratamientos consistieron en combinaciones de maiz extruido (EC y maiz molido (GC EC-10 (10% EC-30% GC; EC-25 (25% EC-15% GC y EC-40 (40% EC-0% GC. Estos alimentos constituyeron el 40% de la ración (base MS y el restante 60% fue ensilaje de pradera. Se estimó la MPS a través de la excreción de derivados de purinas (PD en la orina, empleando colección total de orina. La inclusión de un mayor porcentaje de EC (EC-40 incrementó la excreción de PD (51.85 mmol d-1, P < 0,05. Los valores de excreción de PD fluctuaron entre 663 y 1078 μmol BW-075 d-1. La absorción de proteína microbiana y el flujo de N duodenal también se incrementaron por una mayor inclusión de EC (EC-40, P < 0,05. Las diferencias entre los tratamientos pueden

  12. Enhancement of superoxide dismutase and catalase activity in juvenile brown shrimp, Farfantepenaeus californiensis (Holmes, 1900, fed β-1.3 glucan vitamin E, and β-carotene and infected with white spot syndrome virus Incremento de la actividad superóxido dismutasa y catalasa en juveniles de camarón café Farfantepenaeus californiensis (Holmes, 1900 alimentados con β-1,3 glucano vitamina E y β-caroteno e infectados con el virus de la mancha blanca

    Directory of Open Access Journals (Sweden)

    Rosario Pacheco

    2011-11-01

    contenedores de fibra de vidrio de 60 L y se alimentaron diariamente durante 23 días con β-1,3-glucano (0,1%, vitamina E (0,01%, y β-caroteno (0,01% y posteriormente se inocularon con WSSV. Se determinó la actividad antioxidante de la enzima superóxido dismutasa (SOD y catalasa (CAT en hepatopáncreas y músculo a las 0, 1, 6, 12, 24 y 48 h después de la infección. Los grupos de camarones alimentados con los tratamientos incrementaron la actividad SOD en el hepatopáncreas y músculo a las 12 y 24 h después de la infección, respectivamente. Los juveniles tratados con vitamina E y β-1,3-glucano mantuvieron un incremento en la actividad SOD desde las 12 a 48 h postinfección. Los camarones alimentados con β-caroteno incrementaron la actividad de SOD antes de la infección con WSSV y los que fueron alimentados con β-1,3-glucano y vitamina E incrementaron la actividad CAT también antes de la infección. La actividad CAT en músculo se incrementó respecto al grupo control, con todos los grupos de camarones tratados desde 1 hasta 6 h posteriores a la inoculación con WSSV. La actividad antioxidante más alta se registró en los camarones alimentados con vitamina E. Los juveniles alimentados con vitamina E y posteriormente inoculados con WSSV, registraron 100% de mortalidad a las 72 h, pero los que fueron alimentados con β-1,3-glucano y β-caroteno resistieron la infección hasta las 144 h. Los resultados de Antioxidant response in F. californiensis fed with dietary supplements and infected with WSSV este estudio mostraron la capacidad de juveniles de Farfantepenaeus californiensis alimentados con β-1,3-glucano, vitamina E o β-caroteno, de incrementar la respuesta antioxidante antes y durante una infección viral.

  13. Respuesta productiva de conejos alimentados con forraje verde hidropónico de avena, como reemplazo parcial de concentrado comercial Productive response of rabbits fed with green hydroponic oats forage as partial replacement of commercial concentrate

    Directory of Open Access Journals (Sweden)

    Francisco Fabián Fuentes Carmona

    2011-04-01

    Full Text Available La respuesta productiva de conejos raza californiana alimentados con forraje verde hidropónico (FVH de avena como reemplazo parcial de concentrado comercial (CC, fue evaluada en condiciones de desierto en el norte de Chile. Se establecieron cinco tratamientos de alimentación, equivalentes a 0, 25, 50, 75 y 100% de reemplazo de la dieta diaria con FVH, el cual fue cosechado y utilizado directamente diez días después de la siembra. Cuarenta y cinco conejos destetados a los 31 días fueron evaluados en un diseño completamente al azar hasta alcanzar un peso de sacrificio de 2 kg de peso vivo. La calidad del FVH de avena fue considerada como buena, presentando similar valor nutritivo que el CC. Las variables evaluadas y sus respectivos rangos fueron: consumo de materia seca promedio (59.17 - 104.73 g/día, ganancia de peso vivo promedio (16.35 - 29.10 g/animal por día, conversión alimenticia promedio (3.31 - 3.93 kg MS/kg PV, tiempo de peso vivo a sacrificio (53 - 91 días, peso vivo final (1430 - 2044 g/animal, peso de la canal (1235 - 1385 g/animal y rendimiento de la canal (59.19 - 62.25%. El reemplazo de hasta 50% de la dieta base con FVH de avena no afectó significativamente (P The productive response of Californian rabbits fed with hydroponic green oats forage (HGOF as a partial replacement of commercial concentrate (CC was evaluated under desert conditions in northern Chile. Five treatments were established as follow: 0, 25, 50, 75 and 100% replacement of daily diet with HGOF, which was harvested and used directly at 10 days after sowing. Forty-five rabbits weaned at 31 days were evaluated in a completely randomized design until slaughter weight of 2.0 kg. HGOF quality was considered as good, presenting similar nutritional value to CC. The variables assessed and range values were: average dry matter intake (59.17-104.73 g/d, average weight gain (16.35-29.10 g/ rabbit for day, feed conversion average (3.31-3.93 kg DM/ kg LW, time of

  14. Comparación de la ganancia de peso de neonatos prematuros alimentados con lactancia materna exclusiva con énfasis en la fracción emulsión, lactancia mixta y sucedáneos

    OpenAIRE

    Gloria Velásquez Barahona

    2014-01-01

    Objetivo: Determinar si los bebés prematuros que se alimentaban con lactancia materna exclusiva con énfasis en la fracción emulsión, ganaban peso adecuadamente, comparable a los que se alimentan con lactancia mixta o sucedáneos  y así obtener evidencia clínica que apoye el uso de lactancia materna exclusiva, utilizando esta técnica, en los neonatos prematuros. Método: El estudio fue de tipo experimental longitudinal por  2 meses y medio entre el 31 de agosto al 27 de septiembre del año 2007 e...

  15. Comparación de la ganancia de peso de neonatos prematuros alimentados con lactancia materna exclusiva con énfasis en la fracción emulsión, lactancia mixta y sucedáneos

    OpenAIRE

    Velásquez Barahona, Gloria

    2015-01-01

    Objetivo: Determinar si los bebés prematuros que se alimentaban con lactancia materna exclusiva con énfasis en la fracción emulsión, ganaban peso adecuadamente, comparable a los que se alimentan con lactancia mixta o sucedáneos  y así obtener evidencia clínica que apoye el uso de lactancia materna exclusiva, utilizando esta técnica, en los neonatos prematuros. Método: El estudio fue de tipo experimental longitudinal por  2 meses y medio entre el 31 de agosto al 27 de septiembre del año 2007 e...

  16. Comparación de la ganancia de peso de neonatos prematuros alimentados con lactancia materna exclusiva con énfasis en la fracción emulsión, lactancia mixta y sucedáneos

    Directory of Open Access Journals (Sweden)

    Gloria Velásquez Barahona

    2014-09-01

    Full Text Available Objetivo: Determinar si los bebés prematuros que se alimentaban con lactancia materna exclusiva con énfasis en la fracción emulsión, ganaban peso adecuadamente, comparable a los que se alimentan con lactancia mixta o sucedáneos  y así obtener evidencia clínica que apoye el uso de lactancia materna exclusiva, utilizando esta técnica, en los neonatos prematuros. Método: El estudio fue de tipo experimental longitudinal por  2 meses y medio entre el 31 de agosto al 27 de septiembre del año 2007 en la consulta externa de niño sano del Hospital Roosevelt.  Se enroló a un total de 48 pacientes.  A cada paciente se le tomó las medidas antropométricas de peso y talla, y se siguieron por el período necesario para que alcanzaran un peso de 2.5kg. Resultados: El total de neonatos estudiados fue de 40.  La mayoría pesaron al nacer entre 1000 a 1500g  Los neonatos que recibían lactancia mixta conformaron el mayor grupo.  La media de ganancia diaria de peso de los neonatos que recibía LM exclusiva fue de 32g, los que utilizaban LM mixta fue de 32.4g y los que utilizaban sucedáneos fue de 36.2 g.  Al comparar la media de ganancia de peso de los tres grupos, se encontró que no existía diferencia estadísticamente significativa (p = 0.32.  Así mismo,  no existió  diferencia estadísticamente significativa en la ganancia diaria de talla. (p = 0.44. Conclusiones: Se  evidenció clínicamente que se obtienen ganancias de peso y talla adecuadas utilizando lactancia materna exclusiva comparables a las obtenidas utilizando lactancia mixta y sucedáneos.

  17. Utilización de piensos criollos con harina de Albizia lebbeck para la ceba de conejos alimentados con bejuco de boniato Use of home-made concentrate feed with Albizia lebbeck meal for fattening rabbits fed sweet potato vines

    Directory of Open Access Journals (Sweden)

    I. L Montejo

    2010-03-01

    Full Text Available Se realizó un experimento durante 40 días en el módulo de animales menores de la Estación Experimental de Pastos y Forrajes "Indio Hatuey", con el objetivo de evaluar la inclusión de la harina de Albizia lebbeck en un pienso criollo con diferentes suplementos energético-proteicos, para la alimentación de conejos de ceba. Se utilizaron 26 animales mestizos sanos, de 60 días de edad y 0,94 (± 0,10 kg de peso, en un diseño completamente aleatorizado con dos tratamientos (13 animales por cada uno; estos fueron: A 100% bejuco de boniato (Ipomoea batata y B 70% bejuco de boniato más 30% de pienso criollo elaborado con harina de A. lebbeck y diferentes suplementos energético-proteicos. El alimento se ofreció en los horarios de la mañana (9:00-10:00 a.m. y la tarde (3:00-4:00 p.m.. Se encontraron diferencias significativas en el peso final de los animales (A-1,47 kg y B-1,62 kg. Las mejores ganancias de peso vivo se observaron en el tratamiento suplementado B (16,3 g/animal/día, que fueron superiores (PA trial was conducted for 40 days in the small animal facility of the Experimental Station of Pastures and Forages "Indio Hatuey", with the objective of evaluating the inclusion of Albizia lebbeck meal in a home-made concentrate feed with different energy-protein supplements, to feed fattening rabbits. Twenty-six healthy crossbred animals, 60 days old and with 0,94 (±0,10 kg of weight, were used in a completely randomized design with two treatments (13 animals each; they were: A 100% sweet potato (Ipomoea batata vines and B 70% sweet potato vines + 30% home-made concentrate feed elaborated with A. lebbeck meal and different energy-protein supplements. The feed was supplied in the morning (9:00-10:00 a.m. and the afternoon (3:00-4:00 p.m.. Significant differences were found in the final weight of the animals (A-1,47 kg and B-1,62 kg. The best live weight gains were observed in the supplemented treatment B (16,3 g/animal/day, which were

  18. Restauración de la inmunocompetencia en ratones malnutridos con la administración de un hidrolizado de microalgas

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    Humberto Joaquín Morris Quevedo

    2003-12-01

    Full Text Available Se evaluó el efecto de la administración intraperitoneal de un hidrolizado proteico de la microalga Chlorella vulgaris en una dosis de 500 mg/kg de peso durante 6 días, como complemento de la dieta convencional en la recuperación de la inmunocompetencia de ratones Balb/c con malnutrición proteico-energética inducida experimentalmente por restricción dietética. La intervención con el hidrolizado implicó la restauración del conteo de leucocitos totales a valores similares a los del grupo control; a un incremento en los niveles de linfocitos en sangre periférica; estimuló la proliferación de las células del sistema fagocítico mononuclear y el metabolismo de los macrófagos, expresado por una mayor actividad de la enzima fosfatasa ácida lisosomal y al aumento del peso relativo y actividad hematopoyética del bazo. Estas acciones moduladoras permiten considerar al producto como un preparado inmunológicamente activo capaz de inducir un estado incrementado de resistencia no específica en el organismo.The effect of the intraperitoneal administration of a protein hydrolysate of Chlorella vulgaris microalga at a dose of 500 mg/kg of weight during 6 days, as a supplement of the conventional diet in the recovery of the immunocompetence of Balb/c mice with protein-energy malnutrition experimentally induced by diet restriction, was evaluated. The intervention with the hydrolysate led to the restoration of the count of total leukocytes at values similar to those of the control group and to an increase in the levels of lymphocytes in peripheral blood. It also stimulated the proliferation of the cells from the mononuclear phagocytic system and the metabolism of the macrophages, expressed by a higher activity of the lysosomal acid phsosphatase and the rise of the relative weight and the hematopoietic activity of the spleen. These modullating actions allow to consider the product as an immunological active compound capable of inducing an

  19. Public health intervention linked to a toxic microalgae bloom in Mijas beach (Malaga, Spain); Intervencion en salud publica relacionada con la proliferacion de microalgas toxicas en una playa de Mijas (Malaga; Espana)

    Energy Technology Data Exchange (ETDEWEB)

    Gamez de la Hoz, J.; Padilla Fortes, A.

    2012-07-01

    This paper provide an overview of the surveillance environmental efforts and risk management for the public health linked to the register of a disease outbreak related to an episode of toxic potentially and harmful microalgae, identified during the summer of 2010 in a recreational beach of a touristic municipality in the coast of Malaga (Spain). Phytoplankton analyses showed the presence of different species producers of marine biotoxins, dominating Ostreopsis cf. ovata in the followed immediately days to the communication of 39 clinical cases of people that required health cares. The risks of the toxins produced by microalgae must be taken into account in the health networks surveillance for recreational waters. This study suggests the possibility to review the actions of the public health services from Public Administration, to the light of the increasing information on episodic harmful algal blooms. (Author)

  20. Analytical Issues on the Determination of Carotenoids in Microalgae by Liquid Chromatography with Diode Array Detector; Aspectos Analiticos sobre la Determinacion de Compuestos Carotenoides en Microalgas mediante Cromatografia de Liquidos con Detector de Diodos

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, S.; Perez, R. M.

    2012-04-11

    A preliminary study of literature review on the determination of carotenoids in microalgae samples by HPLC with diode array detector is presented. Main objective has been focused to compile data from literature and based on the main aspects of the analytical methodology used in the determination of these compounds. The work is structured as follows and affecting major analytical difficulties: Procurement and commercial availability of standard solutions. Stage of sample treatment. Chromatographic analysis. (Author) 19 refs.

  1. Diseño y Construcción de un sistema de Ozonificación para purificación de agua alimentado con Energía Solar.

    OpenAIRE

    Sànchez Vega, Guadalupe Omar

    2016-01-01

    En el trabajo que a continuación se presenta se realizó el diseño y construcción de un sistema de purificación de agua por medio del proceso de ozonificación que opera totalmente con energía solar. Para su dimensionamiento se tomaron en cuenta gran cantidad de variables (como la presión del gas de alimentación, voltaje, frecuencia, por destacar algunas) para obtener una mayor cantidad de ozono con bajos consumos energéticos, los cuales son capaces de ser abastecidos con una pila de 12 V y 17 ...

  2. Microalgae Nutraceuticals

    Science.gov (United States)

    Nicoletti, Marcello

    2016-01-01

    Among the new entries in the food supplements sector, an important place must be assigned to nutraceuticals containing microalgae, nowadays accounting for a large and rapidly expanding market. The marketed products are mainly based on three production strains, i.e., Spirulina and Chlorella, followed at a distance by Klamath. It is a composite situation, since two of them are cyanobacteria and the second one is eukaryotic. The reality is that each presents similarities in shape and appearance concerning the marketed form and several utilizations, and peculiarities that need special attention and adequate studies. First, general information is reported about the current scientific knowledge on each microalga, in particular the nutritional value and properties in prevention and wellbeing. Second, original studies are presented concerning the quality control of marketed products. Quality control is a key argument in nutraceuticals validation. Microalgae are particular organisms that need specific approaches to confirm identity and validate properties. The proposed control of quality is based on microscopic analysis of the morphologic characteristics. The final parts of this paper are dedicated to the need for specificity in uses and claims and to considerations about the future of microalgae in food supplements. PMID:28231149

  3. Microalgae Nutraceuticals

    Directory of Open Access Journals (Sweden)

    Marcello Nicoletti

    2016-08-01

    Full Text Available Among the new entries in the food supplements sector, an important place must be assigned to nutraceuticals containing microalgae, nowadays accounting for a large and rapidly expanding market. The marketed products are mainly based on three production strains, i.e., Spirulina and Chlorella, followed at a distance by Klamath. It is a composite situation, since two of them are cyanobacteria and the second one is eukaryotic. The reality is that each presents similarities in shape and appearance concerning the marketed form and several utilizations, and peculiarities that need special attention and adequate studies. First, general information is reported about the current scientific knowledge on each microalga, in particular the nutritional value and properties in prevention and wellbeing. Second, original studies are presented concerning the quality control of marketed products. Quality control is a key argument in nutraceuticals validation. Microalgae are particular organisms that need specific approaches to confirm identity and validate properties. The proposed control of quality is based on microscopic analysis of the morphologic characteristics. The final parts of this paper are dedicated to the need for specificity in uses and claims and to considerations about the future of microalgae in food supplements.

  4. Composición química y calidad sensorial de jamones curados provenientes de cerdos alimentados con una dieta rica en ácido oleico y pasturas

    OpenAIRE

    Ana Echenique; Luis Repiso; Gustavo Capra

    2011-01-01

    La dieta animal es uno de los factores que más incide sobre la calidad de los productos porcinos. En este trabajo se evaluó el efecto de la utilización de semilla de girasol de alto oleico (SGAO) y pasturas sobre la calidad química y sensorial del jamón curado. Se analizaron jamones provenientes de 60 cerdos faenados a los 145 kg. Éstos fueron sometidos a cuatro tratamientos, consistentes en el suministro de dietas con diferente aporte lipídico en cantidad y composición química, con y sin acc...

  5. Composición química y calidad sensorial de jamones curados provenientes de cerdos alimentados con una dieta rica en ácido oleico y pasturas

    Directory of Open Access Journals (Sweden)

    Ana Echenique

    2011-05-01

    Full Text Available La dieta animal es uno de los factores que más incide sobre la calidad de los productos porcinos. En este trabajo se evaluó el efecto de la utilización de semilla de girasol de alto oleico (SGAO y pasturas sobre la calidad química y sensorial del jamón curado. Se analizaron jamones provenientes de 60 cerdos faenados a los 145 kg. Éstos fueron sometidos a cuatro tratamientos, consistentes en el suministro de dietas con diferente aporte lipídico en cantidad y composición química, con y sin acceso a pasturas: i ración estándar, sin pasturas; ii ración estándar, con pasturas; iii ración con SGAO, sin pasturas, y iv ración con SGAO, con pasturas.Se evaluaron parámetros físico-químicos y sensoriales de jamones obtenidos luego de un curado tradicional de nueve meses. La ración con SGAO dio lugar a jamones con una mayor proporción de C18:1(9 y menor de ácidos grasos saturados en relación a la estándar. Las pasturas incidieron sobre el color y determinaron una mayor proporción de C18:3(3 y C22:6(3. Se concluye que con una dieta compuesta por SGAO y pasturas se obtienen jamones con mayor proporción de ácidos grasos oleico y 3 yrelaciones 6/3 más favorables para la salud humana, sin que se vean afectados atributos sensoriales.Palabras clave: Porcinos, sistema de alimentación, ácidos grasos, calidad.AbstractOne of the most important factors that determine the quality of pork products is the pig´s diet. This study was performed to evaluate the use of sun ower seed with high oleic acid (HOSS and the use of pastures on the chemical and sensorial quality of dry-cured ham. Dry-cured hams from 60 pigs slaughtered at 145 kg were analyzed. These animals were fed with two diets with different lipid content and chemical composition, and with and without access to pastures: i standard diet without pastures;ii standard diet with pastures; iii diet with HOSS without pastures and iv diet with HOSS with pastures. Dry-cured hams obtained after

  6. Efecto de la coinmovilización de la microalga Chlorella sorokiniana con la bacteria promotora de crecimiento vegetal Azospirillum brasilense, en el crecimiento poblacional microalgal y capacidad de remoción de amonio como uso potencial en el tratamiento..

    Directory of Open Access Journals (Sweden)

    Lina María González González

    2006-01-01

    de C. sorokiniana con A. brasilense, muestra la habilidad de esta bacteria para influir de manera positiva en el crecimiento y fisiología de la microalga y por lo tanto la remoción de amonio puede ser incrementada.

  7. Parámetros hematológicos y bioquímicos en el hámster dorado (Mesocricetus auratus L. alimentado con base en harina de lombriz roja (Eisenia spp. y fuentes convencionales

    Directory of Open Access Journals (Sweden)

    L. Cova

    2011-01-01

    Full Text Available Se evaluó durante 21 días el efecto de cuatro dietas proteicas con base en harina de Lombriz Roja (Hl (Eisenia spp. (nivel de inclusión de Hl: D1: 21; D2: 24; D3: 27 y D4: 30% y dos alimentos convencionales: Conejarina ® (D0 y Ratarina® (D5 en algunos parámetros hematológicos y bioquímicos en el hámster dorado (Mesocrisetus auratus L. mediante un diseño totalmente aleatorizado para un factor, en el estado Trujillo, Venezuela. El hematocrito (37.65-41.01%, la hemoglobina (10.83-12.25%, la bilirrubina total, directa e indirecta (0.20-0.40; 0.10-0.22; 0.10-0.20mg/ dL, respectivamente, las lipoproteínas de muy baja densidad (Vldl (15.12-41.27mg/dL; los triglicéridos (95.42-190.54mg/dL; así como los valores de Calcio (Ca (9.83-12.32 mg/dL y Potasio (4.24-5.43mg/dL no exhibieron diferencias significativas entre dietas (P>0,05. Los leucocitos (Lto, las plaquetas (Plq, el conteo diferencial (neutrófilos/linfocitos (Linf/eosinófilos, la glicemia (Glc, la amilasa, el colesterol total, las lipoproteínas de elevada (Hdl y baja densidad y el Fósforo mostraron variaciones sustanciales entre los tratamientos (P<0,05. Los niveles crecientes de proteína de las dietas no afectaron los parámetros evaluados. Sin embargo, se observó una relación negativa entre la inclusión de Hl y las cantidades de Lto (r=-0.76**, Plq (r=-0.76**, Linf (r=-0.71**, Glc (r=-0.58* y Hdl (r=-0.50*. La adición de hl en proporciones de 24, 27 y 30% para obtener alimentos formulados entre 13.5 y 19.6% de proteína, para M. auratus, afecta algunos de los parámetros hematológicos y la concentración sérica de metabolitos relacionados con la composición nutricional de la dieta.

  8. Assessment of Blood Chemistry, Weight Gain and Linear Body Measurements of Pre-Puberal Buck Rabbits Fed Different Levels of Neem (Azadirachta indica A. Juss. Leaf Meals Evaluación de Química Sanguínea, Ganancia de Peso y Mediciones Corporales Lineales de Conejos Pre-Púberes Alimentados con Diferentes Niveles de Harina de Hojas de Neem (Azadirachta indica A. Juss.

    Directory of Open Access Journals (Sweden)

    I.P Ogbuewu

    2010-09-01

    Full Text Available A 16 week feeding trial was carried out to investigate the effect of dietary Neem (Azadirachta indica A. Juss. leaf meal (NLM on body weight gain, linear body measurements and blood chemistry of pre-puberal buck rabbits. Four treatment diets were formulated to contain the NLM at inclusion levels of 0 (control, 5, 10 and 15%. Thirty six crossbred New Zealand white × Chinchilla pre-puberal buck rabbits aged 5 to 6 mo were divided into four groups of nine rabbits and each group was further replicated into three of three rabbits each. The rabbits were randomly assigned to the four dietary treatments. Lymphocyte count of rabbits fed control diet (8.32 × 10(9 mm-3 was significantly higher than the group fed 15% NLM (4.60 × 10(9 mm-3. The mean cell hemoglobin (MCH and mean cell volume (MCV of the control bucks were significantly (p 0.05 among the treatment groups. The results suggest that buck rabbits could tolerate up to 15% dietary inclusion of NLM without deleterious effects on body weight gain, linear body measurements and some hematological parameters.Se realizó un ensayo de alimentación de 16 semanas para investigar el efecto de harina de hojas de neem Azadirachta indica A. Juss. (NML sobre ganancia de peso, mediciones corporales lineales y química sanguínea de conejos machos pre-púberes. Se formularon cuatro dietas con niveles de inclusión de NLM de 0 (control, 5, 10, y 15%. Treinta y seis conejos híbridos New Zealand white × Chinchilla, pre-púberes, de 5 a 6 meses, se distribuyeron en cuatro grupos de nueve conejos, y cada grupo fue repetido en tres grupos de tres conejos cada uno. Los conejos se asignaron aleatoriamente a las cuatro dietas tratamiento. El recuento de linfocitos de los conejos alimentados con la dieta control (8,32 × 10(9 mm-3 fue significativamente mayor que el grupo alimentado con 15% NLM (4,60 × 10(9 mm-3. La hemoglobina celular media (MCH y el volumen celular medio (MCV de los conejos control fueron

  9. Comparación entre la ganancia de peso de neonatos prematuros alimentados con lactancia materna exclusiva (con énfasis en la fracción emulsión) y los de lactancia mixta o sucedáneos

    OpenAIRE

    Gloria Velásquez-Barahona

    2014-01-01

    Antecedentes. Las intervenciones relacionadas con la alimentación en los neonatos prematuros promueven tanto la salud inmediata como a lo largo de la vida y tienen un impacto significativo en los niveles de morbimortalidad neonatal e infantil (3). Objetivo. Determinar si los bebés prematuros que se alimentaban con lactancia materna exclusiva (LME) con énfasis en la fracción emulsión -final de la toma-, ganaron peso adecuadamente, comparados con los que se alimentan con lactancia mixta (LMM) o...

  10. Brote con síntomas respiratorios en la provincia de Almería por una posible exposición a microalgas tóxicas An epidemic outbreak with respiratory symptoms in the province of Almeria (Spain due to toxic microalgae exposure

    Directory of Open Access Journals (Sweden)

    Pilar Barroso García

    2008-12-01

    Full Text Available Objetivos: Describir un brote con clínica de irritación de las vías respiratorias, notificado en una localidad de la costa almeriense en agosto de 2006, así como la investigación etiológica realizada. Métodos: Estudio descriptivo y de casos y controles. Se dividió la localidad en 3 zonas según su mayor o menor cercanía al mar (de 1 a 3. La sintomatología fue valorada subjetivamente de menor a mayor gravedad (1 a 3. Se estimaron las tasas de ataque (TA. Para relacionar la gravedad de los síntomas por zonas y el tipo de exposición se calcularon las odds ratio (OR y sus intervalos de confianza del 95% (IC95%. También se utilizó la prueba de la χ2 y el test exacto de Fisher. Se realizó una investigación ambiental. Resultados: Se encuestó a 57 casos y 26 controles. Se estimó una TA del 69%. El síntoma más frecuente fue el estornudo (87,7%. Los individuos de la zona 1 presentaron mayor riesgo de padecer sintomatología de más gravedad que los de la zona 3 (OR = 46,7; IC95%: 4,7-2.067,4. Los que indicaron una mayor permanencia fuera de la vivienda tuvieron mayor riesgo de enfermar (OR = 12,2; IC95%: 1,1-615,1. En agua de mar se detectaron 1.200 células/l de dinoflagelados Ostreopsis. Conclusiones: Se trata de un brote con sintomatología respiratoria, con distinto grado de afectación según la cercanía al mar de la vivienda. Según la investigación epidemiológica y ambiental, lo más probable es que se haya debido a la presencia de microalgas tóxicas Ostreopsis.Aim: To describe an outbreak with symptoms of respiratory tract irritation reported in a village located on the Almerian coast in August 2006, as well as the etiological research performed. Methods: We performed a descriptive case-control study. The village was divided into three areas (from 1 to 3 according to the distance from the sea. Symptomatology was subjectively assessed on an ascending severity scale (from 1 to 3. Attack rates (AR were estimated. To correlate

  11. Florecimiento de microalgas relacionado con mortandad masiva de peces en el complejo lagunar Ciénaga Grande de Santa Marta, Caribe colombiano

    OpenAIRE

    Mancera-P., José E.; Vidal-V., Luis A.

    1994-01-01

    Entre los meses de julio y agosto de 1994 un fenómeno discontinuo de muerte masiva de peces se registró en aguas del complejo lagunar de la Ciénaga Grande de Santa Marta, Colombia. El primer evento se presentó del 15 al 19 de julio, el segundo alrededor del día 20 de agosto y el tercero entre el 26 y 31 del mismo mes. La presencia en altas concentraciones de la cianofita filamentosa Cf. Anabaenopsis sp., registrada en la literatura como altamente tóxica, podría estar relacionada con las causa...

  12. MICROALGAE AS TOCOPHEROL PRODUCERS

    Directory of Open Access Journals (Sweden)

    V. M. Mokrosnop

    2014-04-01

    Full Text Available Microalgae are able to accumulate considerable amounts of tocopherols (up to 4 mg/g dry weight. The content of α-tocopherol to plant oils is low, whereas microalgae contain up to 97% of the tocochromanols that provides high bioactivity. The data about the content of tocopherols in eukaryotic microalgae Dunaliella tertiolecta, Nannochloropsis oculata, Isochrysis galbana, Euglena gracilis, Tetraselmis suecica, Diacronema vlkianum, as well as in the cyanobacterium Spirulina platensis are given in the paper. The largest amounts of tocopherols are synthesized by Euglena gracilis cells at mixotrophic cultivation. The level of tocopherols in microalgae depends on cultivation conditions. Two-stage biotech cultivation techniques, limiting nutrition in some biogenic elements, the introduction of exogenous carbon sources are used to increase the yield of tocopherol from microalgae. The approaches to the genetic transformation of plants leading to higher content of active vitamin E are rewieved as well.

  13. Microalgae: biofuel production

    Directory of Open Access Journals (Sweden)

    Babita Kumari

    2013-04-01

    Full Text Available In the present day, microalgae feedstocks are gaining interest in energy scenario due to their fast growth potential coupled with relatively high lipid, carbohydrate and nutrients contents. All of these properties render them an excellent source for biofuels such as biodiesel, bioethanol and biomethane; as well as a number of other valuable pharmaceutical and nutraceutical products. The present review is a critical appraisal of the commercialization potential of microalgae biofuels. The available literature on various aspects of microalgae for e.g. its cultivation, life cycle assessment, and conceptualization of an algal biorefinery, has been done. The evaluation of available information suggests the operational and maintenance cost along with maximization of oil-rich microalgae production is the key factor for successful commercialization of microalgae-based fuels.

  14. Concentraciones séricas de triyodotironina, tiroxina y perfil lipídico en bovinos lecheros alimentados con una ración con bajo contenido de selenio Serum concentrations of triiodothyronine, thyroxine and lipid profile in dairy cows fed with a low selenium diet

    OpenAIRE

    R Matamoros; A Ceballos; PA Contreras; C Quiroga; M Andaur; F Wittwer

    2008-01-01

    El objetivo de este estudio fue evaluar el efecto de un bajo consumo de Se y su suplementación sobre la concentración sérica de T3 y T4 y sobre el perfil lipídico en vacas lactantes bajo estrés oxidativo inducido. Fueron seleccionadas 12 vacas Frisón Negro gestantes, asignadas auno de dos grupos homogéneos, control (n = 6, Se-D) y tratado (n = 6, Se-S) con selenato de bario (BaSe0(4)), ambos recibieron una ración Se-deficiente (el Se en base seca fue 0,03 ppm para la dieta preparto y 0,05 ppm...

  15. Carotenoids in Microalgae.

    Science.gov (United States)

    Henríquez, Vitalia; Escobar, Carolina; Galarza, Janeth; Gimpel, Javier

    Carotenoids are a class of isoprenoids synthesized by all photosynthetic organisms as well as by some non-photosynthetic bacteria and fungi with broad applications in food, feed and cosmetics, and also in the nutraceutical and pharmaceutical industries. Microalgae represent an important source of high-value products, which include carotenoids, among others. Carotenoids play key roles in light harvesting and energy transfer during photosynthesis and in the protection of the photosynthetic apparatus against photooxidative damage. Carotenoids are generally divided into carotenes and xanthophyls, but accumulation in microalgae can also be classified as primary (essential for survival) and secondary (by exposure to specific stimuli).In this chapter, we outline the high value carotenoids produced by commercially important microalgae, their production pathways, the improved production rates that can be achieved by genetic engineering as well as their biotechnological applications.

  16. Food commodities from microalgae.

    Science.gov (United States)

    Draaisma, René B; Wijffels, René H; Slegers, P M Ellen; Brentner, Laura B; Roy, Adip; Barbosa, Maria J

    2013-04-01

    The prospect of sustainable production of food ingredients from photoautotrophic microalgae was reviewed. Clearly, there is scope for microalgal oils to replace functions of major vegetable oils, and in addition to deliver health benefits to food products. Furthermore, with a limited production surface, a substantial portion of the European Union market could be supplied with edible oils and proteins from microalgae. Yet, before microalgal ingredients can become genuinely sustainable and cost effective alternatives for current food commodities, major breakthroughs in production technology and in biorefinery approaches are required. Moreover, before market introduction, evidence on safety of novel microalgal ingredients, is needed. In general, we conclude that microalgae have a great potential as a sustainable feedstock for food commodities. Copyright © 2012 Elsevier Ltd. All rights reserved.

  17. Production of biodiesel from microalgae

    Directory of Open Access Journals (Sweden)

    Danilović Bojana R.

    2014-01-01

    Full Text Available In recent years, more attention has been paid to the use of third generation feedstocs for the production of biodiesel. One of the most promising sources of oil for biodiesel production are microalgae. They are unicellular or colonial photosynthetic organisms, with permanently increasing industrial application in the production of not only chemicals and nutritional supplements but also biodiesel. Biodiesel productivity per hectare of cultivation area can be up to 100 times higher for microalgae than for oil crops. Also, microalgae can grow in a variety of environments that are often unsuitable for agricultural purposes. Microalgae oil content varies in different species and can reach up to 77% of dry biomass, while the oil productivity by the phototrophic cultivation of microalgae is up to 122 mg/l/d. Variations of the growth conditions and the implementation of the genetic engineering can induce the changes in the composition and productivity of microalgal oil. Biodiesel from microalgae can be produced in two ways: by transesterification of oil extracted from biomass or by direct transesterification of algal biomass (so called in situ transesterification. This paper reviews the curent status of microalgae used for the production of biodiesel including their isolation, cultivation, harvesting and conversion to biodiesel. Because of high oil productivity, microalgae will play a significant role in future biodiesel production. The advantages of using microalgae as a source for biofuel production are increased efficiency and reduced cost of production. Also, microalgae do not require a lot of space for growing and do not have a negative impact on the global food and water supplies. Disadvantages of using microalgae are more difficult separation of biomass and the need for further research to develop standardized methods for microalgae cultivation and biodiesel production. Currently, microalgae are not yet sustainable option for the commercial

  18. Estudio de un Motor Stirling con Absorbedor Interno Alimentado con Energía Solar

    OpenAIRE

    Santos Ráez, Isidro María

    2016-01-01

    La importancia de la energía desde un punto de vista socioeconómico es indiscutible, siendo la energía solar una de las fuentes renovables más atractiva e interesante. Dentro de las múltiples aplicaciones del motor Stirling, cabe destacar su empleo en instalaciones solares de concentración (CSP - Sistemas Dish Stirling), donde se ha demostrado que el diseño del mismo juega un papel relevante en la producción de energía eléctrica. En este trabajo se ha realizado un análisis térmico del diseño ...

  19. Functional ingredients from microalgae

    NARCIS (Netherlands)

    Buono, S.; Langellotti, A.L.; Martello, A.; Rinna, F.; Fogliano, V.

    2014-01-01

    A wide variety of natural sources are under investigation to evaluate their possible use for new functional ingredient formulation. Some records attested the traditional and ancient use of wild harvested microalgae as human food but their cultivation for different purposes started about 40 years

  20. Biofuels from Microalgae

    NARCIS (Netherlands)

    Barbosa, M.J.; Wijffels, R.H.

    2013-01-01

    Microalgae are a promising feedstock for sustaineble production of biofuela due to their unique capacity to reach high lipid productivities. Although the promises are there, production costs and energy requirements are high and the technology is still ammature for the production of bulk products. It

  1. Assessment of the toxicity of sediment and seawater polluted by the Prestige fuel spill using bioassays with clams (Venerupis pullastra, Tappes decussatus and Venerupis rhomboideus) and the microalga Skeletonema costatum; Evaluacion de la toxicidad de sedimento y agua de mar contaminados por el vertido de fuel del Prestige, mediante el uso de bioensayos con las almejas Venerupis pullastra, Tappes decussatus y Venerupis rhomboideus y la microalga Skeletonema costatum

    Energy Technology Data Exchange (ETDEWEB)

    Marino-Balsa, J.C.; Perez, P.; Estevez-Blanco, P.; Saco-Alvarez, L.; Fernandez, E.; Beiras, R. [Laboratorio de Ecologia Marina LEM, Facultad de Ciencias, Universidad de Vigo, Galicia (Spain)

    2003-03-15

    In this study we present the early monitoring of the pollution caused by the accident of the Prestige tanker off the Galician coast. To evaluate the toxicity of sediment and water exposed to fuel, three kinds of bioassays were carried out using juvenile clams, clam embryos and microalgae. Firstly, the burrowing behavior of Venerupis pullastra and Tappes decussatus in the sediment collected from two beaches of similar characteristics but different pollution conditions, was studied over 24 h. No significant differences were observed between the two sediments. Secondly, embryogenesis success of Venerupis rhomboideus was recorded after incubation in seawater and elutriates obtained from affected areas. In this case, fuel-polluted seawater showed a marked inhibition of embryogenesis, while sediment elutriates showed moderate toxicity. Parallel bioassays with the diatom Skeletonema costatum were carried out using sediment elutriates and filtered seawater from the sampling sites. The response variable measured was the maximum quantum yield of photosynthesis ({phi}{sub p}o) using a Fast Repetition Rate Fluorometer (FRRF). In the first sampling, significant differences were found in the response of S. costatum cultured in the elutriates as compared to the control after 5 h exposure. The results corresponding to the second sampling showed statistically significant lower values of {phi}{sub p}o in the culture incubated in M2 water as compared with the control, indicating that the water-accommodated fraction of fuel at this site was the most toxic. [Spanish] En este estudio presentamos los primeros resultados obtenidos del control de la contaminacion producida por el accidente del petrolero Prestige en la costa de Galicia. Para evaluar la toxicidad del agua y el sedimento expuestos al fuel, se realizaron tres tipos de bioensayos: usando almejas juveniles, embriones de almeja y una microalga. En los primeros, se evaluo el comportamiento de enterramiento de Venerupis pullastra y

  2. Advances in editing microalgae genomes

    OpenAIRE

    Daboussi, Fayza

    2017-01-01

    There have been significant advances in microalgal genomics over the last decade. Nevertheless, there are still insufficient tools for the manipulation of microalgae genomes and the development of microalgae as industrial biofactories. Several research groups have recently contributed to progress by demonstrating that particular nucleases can be used for targeted and stable modifications of the genomes of some microalgae species. The nucleases include Meganucleases, Zinc Finger nucleases, TAL...

  3. Separation processes in microalgae biorefining

    OpenAIRE

    Nurra, Claudia

    2014-01-01

    This thesis focuses on the development of new approaches for separation processes in biodiesel production from microalgae by membrane technology. Biodiesel production from microalgae is a theme being developed in the last years that still need more investigation in order to reduce its costs. Among all steps involved in the process this thesis focuses the investigation of the microalgae dewatering by using several membrane filtration techniques and on transesterification by using a catalytic m...

  4. Biohydrogen from Microalgae

    Energy Technology Data Exchange (ETDEWEB)

    Dubini, Alexandra; Gonzalez-Ballester, David

    2016-03-01

    This chapter provides an overview of the current state of knowledge of the mechanisms involved in biohydrogen production from microalgae. The known limitations linked to photohydrogen productivity are addressed. Particular attention is given to physiological and molecular strategies to sustain and improve hydrogen production. The impact of different nutrient stresses and the effect of carbon supply on hydrogen production are discussed. The genetic and metabolic engineering approaches for increasing hydrogen production are outlined.

  5. Fuels from microalgae

    Energy Technology Data Exchange (ETDEWEB)

    1989-06-01

    Many species of aquatic plants can provide a source of renewable energy. Some species of microalgae, in particular, produce lipids -- oils that can be extracted and converted to a diesel fuel substitute or to gasoline. Since 1979 the Aquatic Species Program element of the Biofuels Program, has supported fundamental and applied research to develop the technology for using this renewable energy resource. This document, produced by the Solar Technical Information Program, provides an overview of the DOE/SERI Aquatic Species Program element. Chapter 1 is an introduction to the program and to the microalgae. Chapter 2 is an overview of the general principles involved in making fuels from microalgae. It also outlines the technical challenges to producing economic, high-energy transportation fuels. Chapter 3 provides an overview of the Algal Production and Economic Model (APEM). This model was developed by researchers within the program to identify aspects of the process critical to performance with the greatest potential to reduce costs. The analysis using this model has helped direct research sponsored by the program. Finally, Chapter 4 provides an overview of the Aquatic Species Program and describes current research. 28 refs., 17 figs.

  6. Biotechnological exploitation of microalgae.

    Science.gov (United States)

    Gangl, Doris; Zedler, Julie A Z; Rajakumar, Priscilla D; Martinez, Erick M Ramos; Riseley, Anthony; Włodarczyk, Artur; Purton, Saul; Sakuragi, Yumiko; Howe, Christopher J; Jensen, Poul Erik; Robinson, Colin

    2015-12-01

    Microalgae are a diverse group of single-cell photosynthetic organisms that include cyanobacteria and a wide range of eukaryotic algae. A number of microalgae contain high-value compounds such as oils, colorants, and polysaccharides, which are used by the food additive, oil, and cosmetic industries, among others. They offer the potential for rapid growth under photoautotrophic conditions, and they can grow in a wide range of habitats. More recently, the development of genetic tools means that a number of species can be transformed and hence used as cell factories for the production of high-value chemicals or recombinant proteins. In this article, we review exploitation use of microalgae with a special emphasis on genetic engineering approaches to develop cell factories, and the use of synthetic ecology approaches to maximize productivity. We discuss the success stories in these areas, the hurdles that need to be overcome, and the potential for expanding the industry in general. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  7. POTENCIAL BIOTECNOLÓGICO PARA LA PRODUCCIÓN SUSTENTABLE DE BIODIESEL DE MICROALGAS OLEAGINOSAS AISLADAS DEL RÍO ITAYA, LORETO, PERÚ

    OpenAIRE

    Cobos Ruiz, Marianela; Universidad Científica del Perú (Perú).; Castro Gómez, Juan Carlos; Universidad Nacional de la Amazonía Peruana (Perú).; Cerdeira Gutierrez, Luis Alexander; Universidad Nacional de la Amazonía Peruana (Perú).

    2014-01-01

    Las microalgas son una buena alternativa para producir biodiesel, pero la falta de cepas ideales ha impedido la viabilidad económica de estos sistemas de producción. El objetivo fue aislar e identificar microalgas oleaginosas con potencial aplicación para la producción sustentable de biodiesel. Las muestras fueron colectadas del río Itaya y enriquecidas con medio CHU. Las microalgas oleaginosas se identificaron y aislaron con técnicas estándares. Los lípidos totales se extrajeron con solvente...

  8. Phototrophic pigment production with microalgae

    NARCIS (Netherlands)

    Mulders, K.J.M.

    2014-01-01

    Abstract

    Microalgal pigments are regarded as natural alternatives for food colorants. To facilitate optimization of microalgae-based pigment production, this thesis aimed to obtain key insights in the pigment metabolism of phototrophic microalgae, with the main focus on secondary

  9. Phototrophic pigment production with microalgae

    NARCIS (Netherlands)

    Mulders, K.J.M.

    2014-01-01

    Abstract

    Microalgal pigments are regarded as natural alternatives for food colorants. To facilitate optimization of microalgae-based pigment production, this thesis aimed to obtain key insights in the pigment metabolism of phototrophic microalgae, with the main  focus

  10. Microalgae, products and applications

    OpenAIRE

    Derner, Roberto Bianchini; Ohse, Silvana; Villela, Maurício; Carvalho, Sabrina Matos de; Fett, Roseane

    2006-01-01

    Nos últimos anos, muito interesse tem sido focado no potencial biotecnológico das microalgas, principalmente devido à identificação de diversas substâncias sintetizadas por estes organismos. A imensa biodiversidade e conseqüente variabilidade na composição bioquímica da biomassa obtida das culturas microalgais, aliadas ao emprego de melhoramento genético e ao estabelecimento de tecnologia de cultivo em grande escala, vêm permitindo que determinadas espécies sejam comercialmente utilizadas. Ne...

  11. Management of oxidative stress by microalgae.

    Science.gov (United States)

    Cirulis, Judith T; Scott, J Ashley; Ross, Gregory M

    2013-01-01

    The aim of this review is to provide an overview of the current research on oxidative stress in eukaryotic microalgae and the antioxidant compounds microalgae utilize to control oxidative stress. With the potential to exploit microalgae for the large-scale production of antioxidants, interest in how microalgae manage oxidative stress is growing. Microalgae can experience increased levels of oxidative stress and toxicity as a result of environmental conditions, metals, and chemicals. The defence mechanisms for microalgae include antioxidant enzymes such as superoxide dismutase, catalase, peroxidases, and glutathione reductase, as well as non-enzymatic antioxidant molecules such as phytochelatins, pigments, polysaccharides, and polyphenols. Discussed herein are the 3 areas the literature has focused on, including how conditions stress microalgae and how microalgae respond to oxidative stress by managing reactive oxygen species. The third area is how beneficial microalgae antioxidants are when administered to cancerous mammalian cells or to rodents experiencing oxidative stress.

  12. Efecto de la suplementación proteínica en la respuesta productiva de toros alimentados con dietas mixtas basadas en hollejo de cítrico Effect of protein supplementation on the productive response of bulls fed mixed diets based on citrus pulp

    Directory of Open Access Journals (Sweden)

    F Ojeda

    2010-09-01

    Full Text Available Con el objetivo de evaluar el efecto de diferentes fuentes de suplementación proteínica en la ganancia de peso de animales que consumían una dieta mixta a base de hollejo de cítrico, se desarrolló en la Empresa Citrícola "Victoria de Girón" un estudio con machos de la raza Cebú comercial. En el período enero-abril se suministró forraje y hollejo de cítrico fresco a voluntad; los suplementos fueron: 0,5 kg/animal/día de heno; 0,05 kg de sales minerales; 0,04 de urea y 3 kg/animal/día de afrecho de trigo. En el período mayo-julio se ofrecieron los mismos alimentos, pero con variaciones en el suplemento proteínico: 1,5 kg de afrecho de trigo y levadura Saccharomyces. En el primer período, por la alta suplementación con afrecho de trigo y el bajo porcentaje de proteína del forraje (3,7%, su consumo fue menor con respecto al segundo período (6,5 vs 19,8 kg/animal/día. Durante mayo-julio, la inclusión de la levadura Saccharomyces permitió disminuir la cantidad de afrecho de trigo, lograr un mejor empleo de los alimentos voluminosos, no hacer uso de la urea y obtener las mayores ganancias (0,525 vs 0,6 kg/animal/día. La conversión alimentaria mostró valores de13,8 y 14,0. En esta investigación se comprobó la importancia de las fuentes de proteína para lograr mayores ganancias de peso en los ciclos de cebaIn order to evaluate the effect of different sources of protein supplementation on the weight gain of animals that ate a mixed diet based on citrus pulp, a study was conducted at the "Victoria de Girón" Citrus Fruit Firm with bulls from the commercial Zebu breed. In the January-April period, forage and fresh citrus pulp were supplied ad libitum; the supplements were: 0,5 kg/animal/day of hay; 0,05 kg of mineral salts; 0,04 kg of urea and 3 kg/animal/day of wheat bran. In the May-July period the same feedstuffs were fed, but with variations in the protein supplement: 1,5 kg of wheat bran and Saccharomyces yeast. In the first

  13. Cell disruption for microalgae biorefineries.

    Science.gov (United States)

    Günerken, E; D'Hondt, E; Eppink, M H M; Garcia-Gonzalez, L; Elst, K; Wijffels, R H

    2015-01-01

    Microalgae are a potential source for various valuable chemicals for commercial applications ranging from nutraceuticals to fuels. Objective in a biorefinery is to utilize biomass ingredients efficiently similarly to petroleum refineries in which oil is fractionated in fuels and a variety of products with higher value. Downstream processes in microalgae biorefineries consist of different steps whereof cell disruption is the most crucial part. To maintain the functionality of algae biochemicals during cell disruption while obtaining high disruption yields is an important challenge. Despite this need, studies on mild disruption of microalgae cells are limited. This review article focuses on the evaluation of conventional and emerging cell disruption technologies, and a comparison thereof with respect to their potential for the future microalgae biorefineries. The discussed techniques are bead milling, high pressure homogenization, high speed homogenization, ultrasonication, microwave treatment, pulsed electric field treatment, non-mechanical cell disruption and some emerging technologies. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Value added products from microalgae

    CSIR Research Space (South Africa)

    Naidoo, T

    2013-09-01

    Full Text Available Microalgae represent a bio-diverse resource (Metting, 1996; Pulz and Gross, 2004). The complexity of their chemical composition and range of biochemical products make these organisms exploitable resources for valuable and novel products in the food...

  15. Overview of Microalgae Production Technologies

    CSIR Research Space (South Africa)

    Chinnasamy, S

    2015-03-01

    Full Text Available Microalgae are fast becoming a favoured feedstock for the production of advanced biofuels including biodiesel, biocrude, bioethanol, biomethane, green diesel and biojet fuels. Algae for their growth require sunlight, COfrom waste streams...

  16. Microalgae biofuel potentials (review).

    Science.gov (United States)

    Ghasemi, Y; Rasoul-Amini, S; Naseri, A T; Montazeri-Najafabady, N; Mobasher, M A; Dabbagh, F

    2012-01-01

    With the decrease of fossil based fuels and the environmental impact of them over the planet, it seems necessary to seek the sustainable sources of clean energy. Biofuels, is becoming a worldwide leader in the development of renewable energy resources. It is worthwhile to say that algal biofuel production is thought to help stabilize the concentration of carbon dioxide in the atmosphere and decrease global warming impacts. Also, among algal fuels' attractive characteristics, algal biodiesel is non toxic, with no sulfur, highly biodegradable and relatively harmless to the environment if spilled. Algae are capable of producing in excess of 30 times more oil per acre than corn and soybean crops. Currently, algal biofuel production has not been commercialized due to high costs associated with production, harvesting and oil extraction but the technology is progressing. Extensive research was conducted to determine the utilization of microalgae as an energy source and make algae oil production commercially viable.

  17. [Harvesting microalgae via flocculation: a review].

    Science.gov (United States)

    Wan, Chun; Zhang, Xiaoyue; Zhao, Xinqing; Bai, Fengwu

    2015-02-01

    Microalgae have been identified as promising candidates for biorefinery of value-added molecules. The valuable products from microalgae include polyunsaturated fatty acids and pigments, clean and sustainable energy (e.g. biodiesel). Nevertheless, high cost for microalgae biomass harvesting has restricted the industrial application of microalgae. Flocculation, compared with other microalgae harvesting methods, has distinguished itself as a promising method with low cost and easy operation. Here, we reviewed the methods of microalgae harvesting using flocculation, including chemical flocculation, physical flocculation and biological flocculation, and the progress and prospect in bio-flocculation are especially focused. Harvesting microalgae via bio-flocculation, especially using bio-flocculant and microalgal strains that is self-flocculated, is one of the eco-friendly, cost-effective and efficient microalgae harvesting methods.

  18. Decoloración de aguas residuales de una industria de pinturas por la microalga Chlorella sp

    OpenAIRE

    Angulo M, Edgardo; Castellar O, Grey; Cely B, Ma Mercedes; Ibáñez S, Lilia; Prasca M, Lidys

    2017-01-01

    Objetivo. Decolorar aguas residuales obtenidas de una empresa de pinturas, empleando la microalga Chlorella sp., como medio biológico de tratamiento. Materiales y métodos. Muestras de la microalga previamente cultivada con fertilizante como nutriente y fotoperiodos de luz y oscuridad, se tomaron para evaluar el efecto de la concentración inicial de la microalga Chlorella sp., en el proceso de bioremoción. Para tal fin, esta se cultivó a 0.10, 0.20 y 0.30 unidades de absorbancia en biorreactor...

  19. New challenges in microalgae biotechnology.

    Science.gov (United States)

    Valverde, Federico; Romero-Campero, Francisco J; León, Rosa; Guerrero, Miguel G; Serrano, Aurelio

    2016-08-01

    Photosynthetic protists, also called microalgae, have been systematically studied for more than a century. However, only recently broad biotechnological applications have fostered a novel wave of research on their potentialities as sustainable resources of renewable energy as well as valuable industrial and agro-food products. At the recent VII European Congress of Protistology held in Seville, three outstanding examples of different research strategies on microalgae with biotechnological implications were presented, which suggested that integrative approaches will produce very significant advances in this field in the next future. In any case, intense research and the application of systems biology and genetic engineering techniques are absolutely essential to reach the full potential of microalgae as cell-factories of bio-based products and, therefore, could contribute significantly to solve the problems of biosustainability and energy shortage. Copyright © 2016 Elsevier GmbH. All rights reserved.

  20. Flashing light in microalgae biotechnology.

    Science.gov (United States)

    Abu-Ghosh, Said; Fixler, Dror; Dubinsky, Zvy; Iluz, David

    2016-03-01

    Flashing light can enhance photosynthesis and improve the quality and quantity of microalgal biomass, as it can increase the products of interest by magnitudes. Therefore, the integration of flashing light effect into microalgal cultivation systems should be considered. However, microalgae require a balanced mix of the light/dark cycle for higher growth rates, and respond to light intensity differently according to the pigments acquired or lost during the growth. This review highlights recently published results on flashing light effect on microalgae and its applications in biotechnology, as well as the recently developed bioreactors designed to fulfill this effect. It also discusses how this knowledge can be applied in selecting the optimal light frequencies and intensities with specific technical properties for increasing biomass production and/or the yield of the chemicals of interest by microalgae belonging to different genera. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Heavy metal sorption by microalgae

    Energy Technology Data Exchange (ETDEWEB)

    Sandau, E. [IGV - Inst. fuer Getreideverarbeitung GmbH, Bergholz-Rehbruecke (Germany); Sandau, P. [IGV - Inst. fuer Getreideverarbeitung GmbH, Bergholz-Rehbruecke (Germany); Pulz, O. [IGV - Inst. fuer Getreideverarbeitung GmbH, Bergholz-Rehbruecke (Germany)

    1996-12-31

    Viable microalgae are known to be able to accumulate heavy metals (bioaccumulation). Against a background of the increasing environmental risks caused by heavy metals, the microalgae Chlorella vulgaris and Spirulina platensis and their potential for the biological removal of heavy metals from aqueous solutions were taken as an example for investigation. Small-scale cultivation tests (50 l) with Cd-resistant cells of Chlorella vulgaris have shown that approx. 40% of the added 10 mg Cd/l was removed from the solution within seven days. At this heavy metal concentration sensitive cells died. Non-viable microalgae are able to eliminate heavy metal ions in a short time by biosorption in uncomplicated systems, without any toxicity problems. Compared with original biomasses, the sorption capacity of microalgal by-products changes only insignificantly. Their low price makes them economical. (orig.)

  2. Mass Cultivation of Freshwater Microalgae

    Czech Academy of Sciences Publication Activity Database

    Masojídek, Jiří; Torzillo, G.

    2014-01-01

    Roč. 2, č. 2 (2014), s. 1-13 ISSN 0000-0000 R&D Projects: GA MŠk ED2.1.00/03.0110; GA MŠk EE2.3.30.0059 Institutional support: RVO:61388971 Keywords : microalgae * mass cultivation * bio-active compounds Subject RIV: EE - Microbiology, Virology

  3. Circadian rhythms in microalgae production

    NARCIS (Netherlands)

    Winter, de L.

    2015-01-01

    Abstract Thesis: Circadian rhythms in microalgae production

    Lenneke de Winter

    The sun imposes a daily cycle of light and dark on nearly all organisms. The circadian clock evolved to help organisms program their activities at an appropriate time during this daily

  4. Cell disruption for microalgae biorefineries

    NARCIS (Netherlands)

    Günerken, E.; Hondt, d' E.; Eppink, M.H.M.; Garcia-Gonzalez, L.; Elst, K.; Wijffels, R.H.

    2015-01-01

    Microalgae are a potential source for various valuable chemicals for commercial applications ranging from nutraceuticals to fuels. Objective in a biorefinery is to utilize biomass ingredients efficiently similarly to petroleum refineries in which oil is fractionated in fuels and a variety of

  5. Towards industrial products from microalgae

    NARCIS (Netherlands)

    Ruiz Gonzalez, Jesus; Olivieri, Guiseppe; Vree, de J.H.; Bosma, R.; Willems, Philippe; Reith, J.H.; Eppink, M.H.M.; Kleinegris, D.M.M.; Wijffels, R.H.; Barbosa, M.J.

    2016-01-01

    Our society needs new sustainable biobased feedstocks to meet population growth and reduce dependence on fossil fuels. Microalgae are considered one of the most promising feedstocks for sustainable production of food, feed, chemicals, materials and fuels. Our mission is to develop a commercial and

  6. Control digital para convertidor multinivel alimentado con energía solar

    OpenAIRE

    Martínez Hernández, Domitilo

    2006-01-01

    Hoy en día la obtención de formas alternativas de energía eléctrica es un tema que preocupa al ámbito mundial, ya que la dependencia de los recursos no renovables como los hidrocarburos, el carbón mineral y el uranio para la generación de la misma, cada día resulta más costoso debido al agotamiento de los mismos. Una alternativa de solución es la generación de energía eléctrica mediante el aprovechamiento de la energía solar, utilizando paneles solares para la captación ...

  7. Current Status and Prospects of Biodiesel Production from Microalgae

    OpenAIRE

    Xiaodan Wu; Rongsheng Ruan; Zhenyi Du; Yuhuan Liu

    2012-01-01

    Microalgae represent a sustainable energy source because of their high biomass productivity and ability to remove air and water born pollutants. This paper reviews the current status of production and conversion of microalgae, including the advantages of microalgae biodiesel, high density cultivation of microalgae, high-lipid content microalgae selection and metabolic control, and innovative harvesting and processing technologies. The key barriers to commercial production of microalgae biodie...

  8. Current Status and Prospects of Biodiesel Production from Microalgae

    Directory of Open Access Journals (Sweden)

    Yuhuan Liu

    2012-07-01

    Full Text Available Microalgae represent a sustainable energy source because of their high biomass productivity and ability to remove air and water born pollutants. This paper reviews the current status of production and conversion of microalgae, including the advantages of microalgae biodiesel, high density cultivation of microalgae, high-lipid content microalgae selection and metabolic control, and innovative harvesting and processing technologies. The key barriers to commercial production of microalgae biodiesel and future perspective of the technologies are also discussed.

  9. Efficient recovery of uranium using genetically improved microalgae; Recuperacion eficaz de uranio utilizando microalgas geneticamente mejoradas

    Energy Technology Data Exchange (ETDEWEB)

    Lopez-Rodas, V.; Gonzalez Conde, E.; Garcia-Balboa, C.

    2014-07-01

    Although bioaccumulation is an enzymatic process that requires live microalgae bio sorption is based on physicochemical interactions, and it is not necessary that microalgae are alive, whereby dried microalgae biomass achieves the same results. This alternative could represent a new safe and inexpensive way to recover U. (Author)

  10. Optimization of Biofuel Production From Transgenic Microalgae

    Science.gov (United States)

    2013-02-27

    AFRL-OSR-VA-TR-2013-0145 OPTIMIZATION OF BIOFUEL PRODUCTION FROM TRANSGENIC MICROALGAE Richard Sayre Donald Danforth...Technical 20080815 to 20120630 OPTIMIZATION OF BIOFUEL PRODUCTION FROM TRANSGENIC MICROALGAE FA9550-08-1-0451 Richard Sayre Donald Danforth Plant...BIOFUEL PRODUCTION FROM TRANSGENIC MICROALGAE Grant/Contract Number: FA9550-08-1-0451 Reporting Period: Final Report Abstract: We have compared the

  11. Global evaluation of biofuel potential from microalgae

    OpenAIRE

    Moody, Jeffrey W.; McGinty, Christopher M.; Quinn, Jason C.

    2014-01-01

    Research into microalgae as a feedstock for biofuels continues to increase because of the inherent potential advantages it holds over traditional terrestrial feedstocks. However, the true near-term large-scale productivity of microalgae remains uncertain. This study integrates a large-scale, outdoor growth model with historical meteorological data from 4,388 global locations to estimate the current near-term lipid and biomass productivity potential from microalgae cultivated in a photobioreac...

  12. Microalgae Culture Collection: 1984-1985

    Energy Technology Data Exchange (ETDEWEB)

    1984-09-01

    The Microalgae Culture Collection at the Solar Energy Research Institute has been established for the maintenance and distribution of strains that have been characterized for biomass fuel applications.

  13. Production of biofuels obtained from microalgae

    OpenAIRE

    Luis Carlos Fernández-Linares; Jorge Montiel Montoya; Aarón Millán Oropeza; Jesús Agustín Badillo Corona

    2012-01-01

    A review of the situation of bio-fuels in the world, mainly of biodiesel is made. A comparison among the different raw materials for the synthesis of biodiesel is done and it is emphasized in the production of biodiesel from microalgae. The different fresh and salt water micro-algae in its lipid content and productivity are compared. A review of the process of biosynthesis of lipids in microalgae and how to improve the production of lipids in microalgae is shown. It is discussed the importanc...

  14. Microalgae as embedded environmental monitors

    Energy Technology Data Exchange (ETDEWEB)

    Ogburn, Zachary L.; Vogt, Frank, E-mail: fvogt@utk.edu

    2017-02-15

    In marine ecosystems, microalgae are an important component as they transform large quantities of inorganic compounds into biomass and thereby impact environmental chemistry. Of particular relevance is phytoplankton's sequestration of atmospheric CO{sub 2}, a greenhouse gas, and nitrate, one cause of harmful algae blooms. On the other hand, microalgae sensitively respond to changes in their chemical environment, which initiates an adaptation of their chemical composition. Analytical methodologies were developed in this study that utilize microalgae's adaptation as a novel approach for in-situ environmental monitoring. Longterm applications of these novel methods are investigations of environmental impacts on phytoplankton's sequestration performance and their nutritional value to higher organisms feeding on them. In order to analyze the chemical composition of live microalgae cells (Nannochloropsis oculata), FTIR-ATR spectroscopy has been employed. From time series of IR spectra, the formation of bio-sediment can be monitored and it has been shown that the nutrient availability has a small but observable impact. Since this bio-sediment formation is governed by several biological parameters of the cells such as growth rate, size, buoyancy, number of cells, etc., this enables studies of chemical environment's impact on biomass formation and the cells' physical parameters. Moreover, the spectroscopic signature of these microalgae has been determined from cultures grown under 25 different CO{sub 2} and NO{sub 3}{sup −} mixtures (200 ppm-600 ppm CO{sub 2}, 0.35 mM-0.75 mM NO{sub 3}{sup −}). A novel, nonlinear modeling methodology coined ‘Predictor Surfaces’ is being presented by means of which the nonlinear responses of the cells to their chemical environment could reliably be described. This approach has been utilized to measure the CO{sub 2} concentration in the atmosphere over the phytoplankton culture as well as the nitrate

  15. Microalgae as embedded environmental monitors

    International Nuclear Information System (INIS)

    Ogburn, Zachary L.; Vogt, Frank

    2017-01-01

    In marine ecosystems, microalgae are an important component as they transform large quantities of inorganic compounds into biomass and thereby impact environmental chemistry. Of particular relevance is phytoplankton's sequestration of atmospheric CO 2 , a greenhouse gas, and nitrate, one cause of harmful algae blooms. On the other hand, microalgae sensitively respond to changes in their chemical environment, which initiates an adaptation of their chemical composition. Analytical methodologies were developed in this study that utilize microalgae's adaptation as a novel approach for in-situ environmental monitoring. Longterm applications of these novel methods are investigations of environmental impacts on phytoplankton's sequestration performance and their nutritional value to higher organisms feeding on them. In order to analyze the chemical composition of live microalgae cells (Nannochloropsis oculata), FTIR-ATR spectroscopy has been employed. From time series of IR spectra, the formation of bio-sediment can be monitored and it has been shown that the nutrient availability has a small but observable impact. Since this bio-sediment formation is governed by several biological parameters of the cells such as growth rate, size, buoyancy, number of cells, etc., this enables studies of chemical environment's impact on biomass formation and the cells' physical parameters. Moreover, the spectroscopic signature of these microalgae has been determined from cultures grown under 25 different CO 2 and NO 3 − mixtures (200 ppm-600 ppm CO 2 , 0.35 mM-0.75 mM NO 3 − ). A novel, nonlinear modeling methodology coined ‘Predictor Surfaces’ is being presented by means of which the nonlinear responses of the cells to their chemical environment could reliably be described. This approach has been utilized to measure the CO 2 concentration in the atmosphere over the phytoplankton culture as well as the nitrate concentration dissolved in their growing

  16. Biofuels from Microalgae and Seaweeds

    Energy Technology Data Exchange (ETDEWEB)

    Huesemann, Michael H.; Roesijadi, Guritno; Benemann, John; Metting, F. Blaine

    2010-03-01

    8.1 Introduction: Seaweeds and microalgae have a long history of cultivation as sources of commercial products (McHugh 2003; Pulz and Gross 2004). They also have been the subject of extensive investigations related to their potential as fuel source since the 1970s (Chynoweth 2002). As energy costs rise, these photosynthetic organisms are again a focus of interest as potential sources of biofuels, particularly liquid transportation fuels. There have been many recent private sector investments to develop biofuels from microalgae, in part building on a U.S. Department of Energy (DOE) program from 1976 to 1996 which focused on microalgal oil production (Sheehan et al. 1998). Seaweed cultivation has received relatively little attention as a biofuel source in the US, but was the subject of a major research effort by the DOE from 1978 to 1983 (Bird and Benson 1987), and is now the focus of significant interest in Japan, Europe and Korea...

  17. Production of Biodiesel from Microalgae

    OpenAIRE

    Veillette, Marc; Chamoumi, Mostafa; Nikiema, Josiane; Faucheux, Nathalie; Heitz, Michèle

    2012-01-01

    In recent years, more attention has been paid to the use of third generation feedstocs for the production of biodiesel. One of the most promising sources of oil for biodiesel production are microalgae. They are unicellular or colonial photosynthetic organisms, with permanently increasing industrial application in the production of not only chemicals and nutritional supplements but also biodiesel. Biodiesel productivity per hectare of cultivation area can be...

  18. Radares meteorológicos alimentados por vías alternativas; Weather Radars with Power Supply from Alternatives Ways

    Directory of Open Access Journals (Sweden)

    Milagros Diez Rodríguez

    2011-02-01

    Full Text Available La red de radares meteorológicos de Cuba está compuesta por siete radares antiguos (cuatro rusos y tresjaponeses, los cuales son mantenidos y operados por el Instituto de Meteorología de Cuba. En 1997 elInstituto de Meteorología decidió modernizar todos sus radares, tarea que tomó diez años para su ejecución.Los sistemas de accionamiento eléctrico de las antenas también fueron sometidos a la modernización,pero junto a los requerimientos impuestos por el nuevo sistema de adquisición, los sistemas deaccionamiento dibieron cumplir con las exigencias energéticas para ser alimentados de baterías. Esteartículo describe las soluciones técnicas implementadas en el nuevo sistema de accionamiento eléctricode las antenas.  Weather radar network in Cuba is composed by seven old-fashioned radars (four Russian and three Japaneseand they are maintained and operated by Cuban Meteorological Institute. In 1997 Cuban MeteorologicalInstitute decided to modernize all those radars, and this task was accomplished along ten years.Antenna motor drives were also a matter of modernization, but along with restrictions imposed by dataacquisition, drives needed to complain energy restrictions in order to be used with a battery supply. Thispaper describes technical solutions implemented in newly designed antenna motor drives.

  19. Production of biofuels obtained from microalgae

    Directory of Open Access Journals (Sweden)

    Luis Carlos Fernández-Linares

    2012-09-01

    Full Text Available A review of the situation of bio-fuels in the world, mainly of biodiesel is made. A comparison among the different raw materials for the synthesis of biodiesel is done and it is emphasized in the production of biodiesel from microalgae. The different fresh and salt water micro-algae in its lipid content and productivity are compared. A review of the process of biosynthesis of lipids in microalgae and how to improve the production of lipids in microalgae is shown. It is discussed the importance of the genetic manipulation to highly lipid-producing microalgae (example: Botryrococuus braunni, Nannochloropsis sp, Noechlorisoleobundans and Nitschia sp.. A study of the advantages and disadvantages of the different systems of cultivation of microalgae is also made. Finally, it is shown a perspective of biofuels from microalgae. Among the main challenges to overcome to produce biodiesel from microalgae are: the cost of production of biomass, which involves the optimization of media, selection and manipulation of strains and photobioreactors design. The processof separation of biomass, the extraction of oils and by-products, the optimization of the process of transesterification, purification and use of by-products must also be considered.

  20. Microalgae for biofuels production and environmental applications ...

    African Journals Online (AJOL)

    Microalgae can provide several different types of renewable biofuels. These include methane produced by anaerobic digestion of the algal biomass; biodiesel derived from microalgal oil and photobiologically produced biohydrogen. This review presents the current classification of biofuels, with special focus on microalgae ...

  1. Microalgae production in a biofilm photobioreactor

    NARCIS (Netherlands)

    Blanken, Ward

    2016-01-01

    Microalgae can be used to produce high-value compounds, such as pigments or high value fatty acids, or as a feedstock for lower value products such as food and feed compounds, biochemicals, and biofuels. In order to produce these bulk products competitively, it is required to lower microalgae

  2. Microalgae production in a biofilm photobioreactor

    NARCIS (Netherlands)

    Blanken, Ward

    2016-01-01

    Microalgae can be used to produce high-value compounds, such as pigments or high value fatty acids, or as a feedstock for lower value products such as food and feed compounds, biochemicals, and biofuels. In order to produce these bulk products competitively, it is required to lower microalgae

  3. Harvesting and cell disruption of microalgae

    NARCIS (Netherlands)

    Lam, 't Gerard Pieter

    2017-01-01

    Microalgae are a potential feedstock for various products. At the moment, they are already used as feedstock for high-valuable products (e.g. aquaculture and pigments).

    Microalgae pre-dominantly consist out of proteins, lipids and carbohydrates. This makes algae an interesting feedstock

  4. Mechanism behind autoflocculation of unicellular green microalgae

    NARCIS (Netherlands)

    Salim, S.; Kosterink, N.; Tchetkoua Wacka, N.D.; Vermue, M.H.; Wijffels, R.H.

    2014-01-01

    The oleaginous Ettlia texensis is an autoflocculating green microalga that can be used for bio-flocculation of other microalgae species to facilitate harvesting. In this study the mechanism behind autoflocculation of E. texensis was revealed by scanning electron microscopy (SEM) analysis and by

  5. Highly valuable microalgae: biochemical and topological aspects.

    Science.gov (United States)

    Pignolet, Olivier; Jubeau, Sébastien; Vaca-Garcia, Carlos; Michaud, Philippe

    2013-08-01

    The past decade has seen a surge in the interest in microalgae culture for biodiesel production and other applications as renewable biofuels as an alternative to petroleum transport fuels. The development of new technologies for the culture of these photosynthetic microorganisms and improved knowledge of their biochemical composition has spurred innovation in the field of high-value biomolecules. These developments are only economically viable if all the microalgae fractions are valorized in a biorefinery strategy. Achieving this objective requires an understanding of microalgae content and the cellular localization of the main biomolecular families in order to develop efficient harvest and sequential recovery technologies. This review summarizes the state of the art in microalgae compositions and topologies using some examples of the main industrially farmed microalgae.

  6. Pyrolysis characteristics and kinetics of microalgae via thermogravimetric analysis (TGA): A state-of-the-art review.

    Science.gov (United States)

    Bach, Quang-Vu; Chen, Wei-Hsin

    2017-12-01

    Pyrolysis is a promising route for biofuels production from microalgae at moderate temperatures (400-600°C) in an inert atmosphere. Depending on the operating conditions, pyrolysis can produce biochar and/or bio-oil. In practice, knowledge for thermal decomposition characteristics and kinetics of microalgae during pyrolysis is essential for pyrolyzer design and pyrolysis optimization. Recently, the pyrolysis kinetics of microalgae has become a crucial topic and received increasing interest from researchers. Thermogravimetric analysis (TGA) has been employed as a proven technique for studying microalgae pyrolysis in a kinetic control regime. In addition, a number of kinetic models have been applied to process the TGA data for kinetic evaluation and parameters estimation. This paper aims to provide a state-of-the art review on recent research activities in pyrolysis characteristics and kinetics of various microalgae. Common kinetic models predicting the thermal degradation of microalgae are examined and their pros and cons are illustrated. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Desempenho de alevinos de tilápia do Nilo alimentados com folha de mandioca desidratada na dieta

    Directory of Open Access Journals (Sweden)

    E. L. Santos

    2015-10-01

    Full Text Available RESUMOO objetivo foi avaliar o crescimento e a viabilidade econômica de alevinos de tilápia do Nilo (Oreochromis niloticus, alimentados com diferentes níveis de farinha da folha de mandioca desidratada na ração (FFMD. Foram utilizados 80 alevinos distribuídos em 20 recipientes de 18L, constando de sistema de recirculação de água, durante um período de 51 dias. Cem exemplares, alimentados três vezes ao dia até a saciedade, foram distribuídos aleatoriamente em um delineamento experimental inteiramente casualizado, constituindo-se de 4 tratamentos (0, 5, 10 e 15% de adição da FFMD na ração e 5 repetições cada. Os peixes alimentados com 10% de FFMD apresentaram melhor homogeneidade no crescimento. Entretanto, os indivíduos alimentados com inclusão de 5% de FFMD apresentaram homogeneidade de crescimento similar aos alimentados com 10%. Além disso, os peixes alimentados com 5% de FFMD obtiveram melhor desempenho zootécnico e viabilidade econômica da ração. Dessa maneira, recomenda-se a utilização de 5% da farinha de folha de mandioca desidratada em rações para tilápia do Nilo.

  8. Estado actual de las empresas productoras de microalgas destinadas a alimentos y suplementos alimenticios en América Latina

    Directory of Open Access Journals (Sweden)

    Luis Daniel Martínez Angulo

    2017-12-01

    Full Text Available Las microalgas resultan de interés en la producción de alimentos y suplementos debido a su riqueza de nutrientes. Esta revisión tiene como objetivo recopilar información actual sobre el estado de empresas de mediana y gran escala, productoras de biomasa y bioproductos microalgales comercializados como alimento y suplemento alimenticio en América Latina, con el fin de conocer el nivel de desarrollo en la región. El país con mayor cantidad de empresas productoras de alimentos a base de microalgas es Brasil (6, seguido de México, Perú, Chile (2, Ecuador y Cuba (1. El sistema de cultivo más común empleado por empresas latinoamericanas en el comercio de microalgas es el abierto. El organismo más utilizado en productos alimenticios a base de microalgas en Latinoamérica corresponde al género Spirulina. Se ha investigado sobre la composición bioquímica de más de 10 especies de microalgas, a escala de laboratorio. Las microalgas son fuente importante de proteínas y de ácidos grasos del tipo omega-3, así como de vitaminas y minerales. Se evidencia el potencial que tiene Latinoamérica para el desarrollo de nuevas tecnologías de sistemas de cultivo y productos alimenticios a base de microalgas, como alimento para la población como para la exportación. Sin embargo, se requiere de un gran esfuerzo tanto del sector privado como del público para alcanzar los fines.

  9. Magnetically modified microalgae and their applications

    Czech Academy of Sciences Publication Activity Database

    Šafařík, Ivo; Procházková, G.; Pospíšková, K.; Brányik, T.

    2016-01-01

    Roč. 36, č. 5 (2016), s. 931-941 ISSN 0738-8551 R&D Projects: GA ČR GA13-13709S; GA MŠk(CZ) LD13021 Institutional support: RVO:67179843 Keywords : oleaginous chlorella sp * fresh-water microalgae * magnetophoretic separation * high-gradient * harvesting microalgae * alexandrium-fundyense * polymer binder * algal blooms * cells * removal * Harvesting algal cells * magnetic labeling * magnetic modification * magnetic separation * microalgae Subject RIV: EI - Biotechnology ; Bionics Impact factor: 6.542, year: 2016

  10. RESPUESTA ANTAGÓNICA DE MICROORGANISMOS AISLADOS DE LOS CULTIVOS DE MICROALGAS EN EL LABORATORIO DE CULTIVOS MARINOS

    Directory of Open Access Journals (Sweden)

    Carmen Ruíz Huamán

    2013-10-01

    Full Text Available Durante el 2012, el Laboratorio de Cultivos Marinos obtuvo bacterias aisladas de los cultivos de microalgas. Se trabajó 60 colonias de los cultivos. Se confrontó una a una las colonias aisladas del cultivo de microalgas con las bacterias patógenas tipo ATCC, estas fueron: Flavobacterium psychrophilum, Aeromona hydrophila, Lactococcus garviaceae y Vibrio herveyi. Solo una bacteria tuvo interacción antagónica ya que formó el halo de inhibición.

  11. Microalgae as Solar-Powered Protein Factories.

    Science.gov (United States)

    Hempel, Franziska; Maier, Uwe G

    2016-01-01

    Microalgae have an enormous ecological relevance as they contribute significantly to global carbon fixation. But also for biotechnology microalgae became increasingly interesting during the last decades as many algae provide valuable natural products. Especially the high lipid content of some species currently attracts much attention in the biodiesel industry. A further application that emerged some years ago is the use of microalgae as expression platform for recombinant proteins. Several projects on the production of therapeutics, vaccines and feed supplements demonstrated the great potential of using microalgae as novel low-cost expression platform. This review provides an overview on the prospects and advantages of microalgal protein expression systems and gives an outlook on potential future applications.

  12. Biologically Active Metabolites Synthesized by Microalgae

    Directory of Open Access Journals (Sweden)

    Michele Greque de Morais

    2015-01-01

    Full Text Available Microalgae are microorganisms that have different morphological, physiological, and genetic traits that confer the ability to produce different biologically active metabolites. Microalgal biotechnology has become a subject of study for various fields, due to the varied bioproducts that can be obtained from these microorganisms. When microalgal cultivation processes are better understood, microalgae can become an environmentally friendly and economically viable source of compounds of interest, because production can be optimized in a controlled culture. The bioactive compounds derived from microalgae have anti-inflammatory, antimicrobial, and antioxidant activities, among others. Furthermore, these microorganisms have the ability to promote health and reduce the risk of the development of degenerative diseases. In this context, the aim of this review is to discuss bioactive metabolites produced by microalgae for possible applications in the life sciences.

  13. Biologically Active Metabolites Synthesized by Microalgae.

    Science.gov (United States)

    de Morais, Michele Greque; Vaz, Bruna da Silva; de Morais, Etiele Greque; Costa, Jorge Alberto Vieira

    2015-01-01

    Microalgae are microorganisms that have different morphological, physiological, and genetic traits that confer the ability to produce different biologically active metabolites. Microalgal biotechnology has become a subject of study for various fields, due to the varied bioproducts that can be obtained from these microorganisms. When microalgal cultivation processes are better understood, microalgae can become an environmentally friendly and economically viable source of compounds of interest, because production can be optimized in a controlled culture. The bioactive compounds derived from microalgae have anti-inflammatory, antimicrobial, and antioxidant activities, among others. Furthermore, these microorganisms have the ability to promote health and reduce the risk of the development of degenerative diseases. In this context, the aim of this review is to discuss bioactive metabolites produced by microalgae for possible applications in the life sciences.

  14. Screening of antioxidant activity in microalgae

    Directory of Open Access Journals (Sweden)

    Mariana F.G. Assunção

    2014-06-01

    Both sets of results indicate an interesting antioxidant potential in microalgae belonging to the groups Eustigmatophyceae and Chlorophyceae. Tested species of these groups showed ABTS•+ values comparable to grape and raspberry ethanolic extracts, confirmed also by the DPPH• method.

  15. Modeling and visual simulation of Microalgae photobioreactor

    Science.gov (United States)

    Zhao, Ming; Hou, Dapeng; Hu, Dawei

    Microalgae is a kind of nutritious and high photosynthetic efficiency autotrophic plant, which is widely distributed in the land and the sea. It can be extensively used in medicine, food, aerospace, biotechnology, environmental protection and other fields. Photobioreactor which is important equipment is mainly used to cultivate massive and high-density microalgae. In this paper, based on the mathematical model of microalgae which grew under different light intensity, three-dimensional visualization model was built and implemented in 3ds max, Virtools and some other three dimensional software. Microalgae is photosynthetic organism, it can efficiently produce oxygen and absorb carbon dioxide. The goal of the visual simulation is to display its change and impacting on oxygen and carbon dioxide intuitively. In this paper, different temperatures and light intensities were selected to control the photobioreactor, and dynamic change of microalgal biomass, Oxygen and carbon dioxide was observed with the aim of providing visualization support for microalgal and photobioreactor research.

  16. Biologically Active Metabolites Synthesized by Microalgae

    Science.gov (United States)

    Costa, Jorge Alberto Vieira

    2015-01-01

    Microalgae are microorganisms that have different morphological, physiological, and genetic traits that confer the ability to produce different biologically active metabolites. Microalgal biotechnology has become a subject of study for various fields, due to the varied bioproducts that can be obtained from these microorganisms. When microalgal cultivation processes are better understood, microalgae can become an environmentally friendly and economically viable source of compounds of interest, because production can be optimized in a controlled culture. The bioactive compounds derived from microalgae have anti-inflammatory, antimicrobial, and antioxidant activities, among others. Furthermore, these microorganisms have the ability to promote health and reduce the risk of the development of degenerative diseases. In this context, the aim of this review is to discuss bioactive metabolites produced by microalgae for possible applications in the life sciences. PMID:26339647

  17. Microalgae, old sustainable food and fashion nutraceuticals.

    Science.gov (United States)

    García, José L; de Vicente, Marta; Galán, Beatriz

    2017-09-01

    Microalgae have been used for centuries to provide nourishment to humans and animals, only very recently they have become much more widely cultured and harvested at large industrial scale. This paper reviews the potential health benefits and nutrition provided by microalgae whose benefits are contributing to expand their market. We also point out several key challenges that remain to be addressed in this field. © 2017 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

  18. From tiny microalgae to huge biorefineries

    OpenAIRE

    Gouveia, L.

    2014-01-01

    Microalgae are an emerging research field due to their high potential as a source of several biofuels in addition to the fact that they have a high-nutritional value and contain compounds that have health benefits. They are also highly used for water stream bioremediation and carbon dioxide mitigation. Therefore, the tiny microalgae could lead to a huge source of compounds and products, giving a good example of a real biorefinery approach. This work shows and presents examples of experimental...

  19. Microalgae for biofuels: the Portuguese experience

    OpenAIRE

    Gouveia, L.; Reis, Alberto; Moura, Patrícia; Oliveira, A. C.; Gírio, Francisco M.

    2015-01-01

    Autotrophic microalgae are photosynthetic organisms that undergo the conversion of light into chemical energy as a form of a wide range of organic compounds through its photosynthetic machinery. The cultivation of microalgae brings environmental advantages, bearing in mind the capability of nutrient recycling in wastewaters together with the fixation of greenhouse gases such as CO2. These micro-organisms have been widely recognized as having huge potential as feedstock for food, feed, pharmac...

  20. Heavy metal detoxification in eukaryotic microalgae.

    Science.gov (United States)

    Perales-Vela, Hugo Virgilio; Peña-Castro, Julián Mario; Cañizares-Villanueva, Rosa Olivia

    2006-06-01

    Microalgae are aquatic organisms possessing molecular mechanisms that allow them to discriminate non-essential heavy metals from those essential ones for their growth. The different detoxification processes executed by algae are reviewed with special emphasis on those involving the peptides metallothioneins, mainly the post transcriptionally synthesized class III metallothioneins or phytochelatins. Also, the features that make microalgae suitable organisms technologies specially to treat water that is heavily polluted with metals is discussed.

  1. Microalgae biorefinery: High value products perspectives.

    Science.gov (United States)

    Chew, Kit Wayne; Yap, Jing Ying; Show, Pau Loke; Suan, Ng Hui; Juan, Joon Ching; Ling, Tau Chuan; Lee, Duu-Jong; Chang, Jo-Shu

    2017-04-01

    Microalgae have received much interest as a biofuel feedstock in response to the uprising energy crisis, climate change and depletion of natural sources. Development of microalgal biofuels from microalgae does not satisfy the economic feasibility of overwhelming capital investments and operations. Hence, high-value co-products have been produced through the extraction of a fraction of algae to improve the economics of a microalgae biorefinery. Examples of these high-value products are pigments, proteins, lipids, carbohydrates, vitamins and anti-oxidants, with applications in cosmetics, nutritional and pharmaceuticals industries. To promote the sustainability of this process, an innovative microalgae biorefinery structure is implemented through the production of multiple products in the form of high value products and biofuel. This review presents the current challenges in the extraction of high value products from microalgae and its integration in the biorefinery. The economic potential assessment of microalgae biorefinery was evaluated to highlight the feasibility of the process. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Bioremediation of wastewater using microalgae

    Science.gov (United States)

    Chalivendra, Saikumar

    Population expansion and industrial development has deteriorated the quality of freshwater reservoirs around the world and has caused freshwater shortages in certain areas. Discharge of industrial effluents containing toxic heavy metals such as Cd and Cr into the environment have serious impact on human, animal and aquatic life. In order to solve these problems, the present study was focused on evaluating and demonstrating potential of microalgae for bioremediation of wastewater laden with nitrogen (N) in the form of nitrates, phosphorous (P) in the form of phosphates, chromium (Cr (VI)) and cadmium (Cd (II)). After screening several microalgae, Chlorella vulgaris and algae taken from Pleasant Hill Lake were chosen as candidate species for this study. The viability of the process was demonstrated in laboratory bioreactors and various experimental parameters such as contact time, initial metal concentration, algae concentration, pH and temperature that would affect remediation rates were studied. Based on the experimental results, correlations were developed to enable customizing and designing a commercial Algae based Wastewater Treatment System (AWTS). A commercial AWTS system that can be easily customized and is suitable for integration into existing wastewater treatment facilities was developed, and capital cost estimates for system including installation and annual operating costs were determined. The work concludes that algal bioremediation is a viable alternate technology for treating wastewater in an economical and sustainable way when compared to conventional treatment processes. The annual wastewater treatment cost to remove N,P is ~26x lower and to remove Cr, Cd is 7x lower than conventional treatment processes. The cost benefit analysis performed shows that if this technology is implemented at industrial complexes, Air Force freight and other Department of Defense installations with wastewater treatment plants, it could lead to millions of dollars in

  3. Tratamiento y valorización de aguas residuales mediante microalgas

    OpenAIRE

    Bolado Rodríguez, Silvia; Martín Juarez, Judit; Lebrero, Raquel; Pérez Elvira, Sara I.; Garcia, Dimas; Marin, David; Lorenzo Hernando, Ana; García Encina, Pedro A; Muñoz Torre, Raúl

    2016-01-01

    La investigación en procesos biológicos convencionales de tratamiento de aguas residuales ha evolucionado en la última década hacia el desarrollo de sistemas compactos con mayores consumos energéticos (p.ej. biorreactores aerobios de membrana) o que conllevan una pérdida de los nutrientes presentes en el agua residual (p.ej. annamox). El reciente interés a nivel mundial en el cultivo de microalgas con fines energéticos, unido a la necesidad de disponer de tecnologías de tratamiento de aguas r...

  4. Lutein production from biomass: marigold flowers versus microalgae.

    Science.gov (United States)

    Lin, Jian-Hao; Lee, Duu-Jong; Chang, Jo-Shu

    2015-05-01

    Microalgae have faster growth rates and more free lutein than marigold flowers, the current source of lutein. However, no commercial lutein production uses microalgae. This review compares lutein content, cultivation, harvesting, cell disruption, and extraction stages of lutein production using marigold flowers and those using microalgae as feedstock. The lutein production rate of microalgae is 3-6 times higher than that of marigold flowers. To produce 1 kg of pure lutein, marigolds need more land and water, but require less nutrients (N, P, K) and less energy than microalgae. Since lutein is tightly bound in microalgae and microalgae are small, cell disruption and subsequent extraction stages consume a considerable amount of energy. Research and development of affordable lutein production from microalgae are discussed. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Marine microalgae for production of biofuels and chemicals.

    Science.gov (United States)

    Maeda, Yoshiaki; Yoshino, Tomoko; Matsunaga, Tadashi; Matsumoto, Mitsufumi; Tanaka, Tsuyoshi

    2017-12-09

    Marine microalgae are recognized as promising feedstocks for biofuels and chemicals owing to their higher growth rates than those of terrestrial crop plants. We aimed to summarize the production of biofuels and chemicals by marine microalgae and to discuss their advantages and potential from the aspect of bioprocess. The present circumstances of the microalgae industry were briefly described and large-scale industrial plants for microalgae production, where some marine microalgae are cultivated, were introduced. The advantages of marine microalgae in terms of water and land usage were also discussed. Finally, novel genome editing tools that could further exploit the potential of marine microalgae were reviewed. The present study provided comprehensive information regarding current biotechnology using marine microalgae. Copyright © 2017. Published by Elsevier Ltd.

  6. The Potential for Microalgae as Bioreactors to Produce Pharmaceuticals

    Science.gov (United States)

    Yan, Na; Fan, Chengming; Chen, Yuhong; Hu, Zanmin

    2016-01-01

    As photosynthetic organisms, microalgae can efficiently convert solar energy into biomass. Microalgae are currently used as an important source of valuable natural biologically active molecules, such as carotenoids, chlorophyll, long-chain polyunsaturated fatty acids, phycobiliproteins, carotenoids and enzymes. Significant advances have been achieved in microalgae biotechnology over the last decade, and the use of microalgae as bioreactors for expressing recombinant proteins is receiving increased interest. Compared with the bioreactor systems that are currently in use, microalgae may be an attractive alternative for the production of pharmaceuticals, recombinant proteins and other valuable products. Products synthesized via the genetic engineering of microalgae include vaccines, antibodies, enzymes, blood-clotting factors, immune regulators, growth factors, hormones, and other valuable products, such as the anticancer agent Taxol. In this paper, we briefly compare the currently used bioreactor systems, summarize the progress in genetic engineering of microalgae, and discuss the potential for microalgae as bioreactors to produce pharmaceuticals. PMID:27322258

  7. Microalgae as a source of high-value bioactive compounds.

    Science.gov (United States)

    Bule, Mohammed Hussen; Ahmed, Ishtiaq; Maqbool, Faheem; Bilal, Muhammad; Iqbal, Hafiz M N

    2018-01-01

    Microalgae are one of the oldest microorganisms, that grow in various hostile environments, ranging from deserts to Antarctica. The microalgae sustain life in such harsh environments through generation of secondary metabolites. Microalgae biosynthesize a large number of diverse bioactive metabolites with activities on cancer, neurodegenerative diseases, and infectious diseases. Here, we highlight the bioactive compounds that are isolated from microalgae for the purpose of using them as food, and as chemicals in pharmaceutical industry as new agents with therapeutic benefits.

  8. Geographical Assessment of Microalgae Biofuels Potential Incorporating Resource Availability

    OpenAIRE

    Quinn, Jason C.; Catton, Kimberly; Johnson, Sara; Bradley, Thomas H.

    2012-01-01

    Previous assessments of the economic feasibility and large-scale productivity of microalgae biofuels have not considered the impacts of land and carbon dioxide (CO2) availability on the scalability of microalgae-based biofuels production. To accurately assess the near-term productivity potential of large-scale microalgae biofuel in the US, a geographically realized growth model was used to simulate microalgae lipid yields based on meteorological data. The resulting lipid productivity potentia...

  9. Extraction of Bio-oils from Microalgae

    Energy Technology Data Exchange (ETDEWEB)

    Cooney, Michael; Young, Greg; Nagle, Nick

    2009-12-01

    A wide variety of terrestrial biomass feed stocks have been identified as suitable candidates for fractionation and conversion into biofuels. In particular, microalgae have been promoted as a future source of transportation fuels primarily because of their stated potential to produce up to 10 times more oil per acre than traditional biofuel crops. Their ability to grow relatively fast, be harvested on a daily basis, and grown in earthen ponds or closed photobioreactors that occupy marginal or poor crop lands using salt or brackish water, are often referenced. When these attractive traits are coupled with the potential to concomitantly harvest valuable co-products such as biopolymers, proteins, and animal feeds, one can see why microalgae are often touted as biotechnology's “green gold”. The development of large-scale microalgae farms, however, has been slowed by limitations in downstream processing technology. For example, traditional methods to dewater, extract, and recover bio-oil from oil-seeds possess little utility for microalgae. The extreme requirement of dewatering poses tremendous hurdles for any technology processing biofuels from microalgae. To further complicate matters, identifying the most appropriate paths for appropriate extraction technology depends heavily on the microalgal species and its cultivation status, both of which are highly characterized for higher plants as compared to microalgae. In this review we discuss existing extraction methodologies as they have and can be applied to microalgae. Commentary is provided on their potential as a unit operation that exists within the framework of an industrial-scale microalgal cultivation process that extends from the production of biomass in photobioreactors to the fractionation of the recovered bio-oil.

  10. Biofouling in photobioreactors for marine microalgae.

    Science.gov (United States)

    Zeriouh, Ouassim; Reinoso-Moreno, José Vicente; López-Rosales, Lorenzo; Cerón-García, María Del Carmen; Sánchez-Mirón, Asterio; García-Camacho, Francisco; Molina-Grima, Emilio

    2017-12-01

    The economic and/or energetic feasibility of processes based on using microalgae biomass requires an efficient cultivation system. In photobioreactors (PBRs), the adhesion of microalgae to the transparent PBR surfaces leads to biofouling and reduces the solar radiation penetrating the PBR. Light reduction within the PBR decreases biomass productivity and, therefore, the photosynthetic efficiency of the cultivation system. Additionally, PBR biofouling leads to a series of further undesirable events including changes in cell pigmentation, culture degradation, and contamination by invasive microorganisms; all of which can result in the cultivation process having to be stopped. Designing PBR surfaces with proper materials, functional groups or surface coatings, to prevent microalgal adhesion is essential for solving the biofouling problem. Such a significant advance in microalgal biotechnology would enable extended operational periods at high productivity and reduce maintenance costs. In this paper, we review the few systematic studies performed so far and applied the existing thermodynamic and colloidal theories for microbial biofouling formation in order to understand microalgal adhesion on PBR surfaces and the microalgae-microalgae cell interactions. Their relationship to the physicochemical properties of the solid PBR surface, the microalgae cell surfaces, and the ionic strength of the culture medium is discussed. The suitability and the applicability of such theories are reviewed. To this end, an example of biofouling formation on a commercial glass surface is presented for the marine microalgae Nannochloropsis gaditana. It highlights the adhesion dynamics and the inaccuracies of the process and the need for further refinement of previous theories so as to apply them to flowing systems, such as is the case for PBRs used to culture microalgae.

  11. Microalgae bulk growth model with application to industrial scale systems

    NARCIS (Netherlands)

    Quinn, J.; Winter, de L.; Bradley, T.

    2011-01-01

    The scalability of microalgae growth systems is a primary research topic in anticipation of the commercialization of microalgae-based biofuels. To date, there is little published data on the productivity of microalgae in growth systems that are scalable to commercially viable footprints. To inform

  12. Consumo e digestibilidade de nutrientes em ovinos alimentados com sal forrageiro de faveleira (Cnidoscolus phyllacanthus)

    OpenAIRE

    OLIVEIRA,Fernanda Melo de; OLIVEIRA,Gabriel Jorge Carneiro de; OLIVEIRA,Marcos Lemos Andrade de; JAEGER,Soraya Maria Palma Luz; ALMEIDA,Luiz Henrique Silva; NERY,Igor Bomfim Quadros; LEITE,Laudi Cunha

    2016-01-01

    RESUMO Objetivou-se com este estudo avaliar o consumo e a digestibilidade aparente dos nutrientes em ovinos alimentados com sal forrageiro de faveleira (Cnidoscolus phyllacanthus) com níveis crescentes de cloreto de sódio na sua composição. Foram utilizados 25 carneiros, sem padrão racial definido, não castrados, alocados em baias individuais, distribuídos em um delineamento experimental inteiramente casualizado, com cinco tratamentos e cinco repetições. As dietas que continham 1, 3, 5 e 7% d...

  13. Perfil lipídico tecidual de ratos alimentados com diferentes fontes lipídicas

    OpenAIRE

    Almeida,Martha Elisa Ferreira de; Queiroz,José Humberto de; Queiroz,Maria Eliana Lopes Ribeiro de; Costa,Neuza Maria Brunoro; Matta,Sérgio Luis Pinto

    2009-01-01

    OBJETIVO:Determinar se fontes lipídicas com diferentes razões de ácidos graxos insaturados e saturados (PUFA+MUFA)/SFA na dieta altera o perfil lipídico tecidual, a concentração de lipídios (mg/g) dos tecidos hepáticos e mesentérico e a digestibilidade lipídica. MÉTODOS: Foi realizada cromatografia gasosa para determinar o perfil de ácidos graxos nos tecidos hepático e adiposo de ratos alimentados com diferentes fontes lipídicas. O coeficiente de digestibilidade foi determinado a partir da re...

  14. An Overview of Biocement Production from Microalgae

    Directory of Open Access Journals (Sweden)

    Dessy Ariyanti

    2011-12-01

    Full Text Available The invention of microorganism’s involvement in carbonate precipitation, has lead the exploration of this process in the field of construction engineering. Biocement is a product innovation from developing bioprocess technology called biocementation. Biocement refers to CaCO3 deposit that formed due to microorganism activity in the system rich of calcium ion. The primary role of microorganism in carbonate precipitation is mainly due to their ability to create an alkaline environment (high pH and DIC increase through their various physiological activities. Three main groups of microorganism that can induce the carbonate precipitation: (i photosynthetic microorganism such as cyanobacteria and microalgae; (ii sulphate reducing bacteria; and (iii some species of microorganism involved in nitrogen cycle. Microalgae are photosynthetic microorganism and utilize urea using urease or urea amidolyase enzyme, based on that it is possible to use microalgae as media to produce biocement through biocementation. This paper overviews biocement in general, biocementation, type of microorganism and their pathways in inducing carbonate precipitation and the prospect of microalgae to be used in biocement production.  Keywords— Biocement, Biocementation, Microalgae, CaCO3 precipitation

  15. Selenium Utilization Strategy by Microalgae

    Directory of Open Access Journals (Sweden)

    Hiroya Araie

    2009-11-01

    Full Text Available The diversity of selenoproteins raises the question of why so many life forms require selenium. Selenoproteins are found in bacteria, archaea, and many eukaryotes. In photosynthetic microorganisms, the essential requirement for selenium has been reported in 33 species belonging to six phyla, although its biochemical significance is still unclear. According to genome databases, 20 species are defined as selenoprotein-producing organisms, including five photosynthetic organisms. In a marine coccolithophorid, Emiliania huxleyi (Haptophyta, we recently found unique characteristics of selenium utilization and novel selenoproteins using 75Se-tracer experiments. In E. huxleyi, selenite, not selenate, is the main substrate used and its uptake is driven by an ATP-dependent highaffinity, active transport system. Selenite is immediately metabolized to low-molecular mass compounds and partly converted to at least six selenoproteins, named EhSEP1–6. The most (EhSEP2 and second-most abundant selenoproteins (EhSEP1 are disulfide isomerase (PDI homologous protein and thioredoxin reductase (TR 1, respectively. Involvement of selenium in PDI is unique in this organism, while TR1 is also found in other organisms. In this review, we summarize physiological, biochemical, and molecular aspects of selenium utilization by microalgae and discuss their strategy of selenium utilization.

  16. Mixotrophic cultivation of microalgae for biodiesel production: status and prospects.

    Science.gov (United States)

    Wang, Jinghan; Yang, Haizhen; Wang, Feng

    2014-04-01

    Biodiesel from microalgae provides a promising alternative for biofuel production. Microalgae can be produced under three major cultivation modes, namely photoautotrophic cultivation, heterotrophic cultivation, and mixotrophic cultivation. Potentials and practices of biodiesel production from microalgae have been demonstrated mostly focusing on photoautotrophic cultivation; mixotrophic cultivation of microalgae for biodiesel production has rarely been reviewed. This paper summarizes the mechanisms and virtues of mixotrophic microalgae cultivation through comparison with other major cultivation modes. Influencing factors of microalgal biodiesel production under mixotrophic cultivation are presented, development of combining microalgal biodiesel production with wastewater treatment is especially reviewed, and bottlenecks and strategies for future commercial production are also identified.

  17. Harvesting of microalgae biomass from the phycoremediation process of greywater.

    Science.gov (United States)

    Atiku, Hauwa; Mohamed, R M S R; Al-Gheethi, A A; Wurochekke, A A; Kassim, Amir Hashim M

    2016-12-01

    The wide application of microalgae in the field of wastewater treatment and bioenergy source has improved research studies in the past years. Microalgae represent a good source of biomass and bio-products which are used in different medical and industrial activities, among them the production of high-valued products and biofuels. The present review focused on greywater treatment through the application of phycoremediation technique with microalgae and presented recent advances in technologies used for harvesting the microalgae biomass. The advantages and disadvantages of each method are discussed. The microbiological aspects of production, harvesting and utilization of microalgae biomass are viewed.

  18. Availability and Utilization of Pigments from Microalgae.

    Science.gov (United States)

    Begum, Hasina; Yusoff, Fatimah Md; Banerjee, Sanjoy; Khatoon, Helena; Shariff, Mohamed

    2016-10-02

    Microalgae are the major photosynthesizers on earth and produce important pigments that include chlorophyll a, b and c, β-carotene, astaxanthin, xanthophylls, and phycobiliproteins. Presently, synthetic colorants are used in food, cosmetic, nutraceutical, and pharmaceutical industries. However, due to problems associated with the harmful effects of synthetic colorants, exploitation of microalgal pigments as a source of natural colors becomes an attractive option. There are various factors such as nutrient availability, salinity, pH, temperature, light wavelength, and light intensity that affect pigment production in microalgae. This paper reviews the availability and characteristics of microalgal pigments, factors affecting pigment production, and the application of pigments produced from microalgae. The potential of microalgal pigments as a source of natural colors is enormous as an alternative to synthetic coloring agents, which has limited applications due to regulatory practice for health reasons.

  19. Can Microalgae Remove Pharmaceutical Contaminants from Water?

    Science.gov (United States)

    Xiong, Jiu-Qiang; Kurade, Mayur B; Jeon, Byong-Hun

    2018-01-01

    The increase in worldwide water contamination with numerous pharmaceutical contaminants (PCs) has become an emerging environmental concern due to their considerable ecotoxicities and associated health issues. Microalgae-mediated bioremediation of PCs has recently gained scientific attention, as microalgal bioremediation is a solar-power driven, ecologically comprehensive, and sustainable reclamation strategy. In this review, we comprehensively describe the current research on the possible roles and applications of microalgae for removing PCs from aqueous media. We summarize several novel approaches including constructing microbial consortia, acclimation, and cometabolism for enhanced removal of PCs by microalgae, which would improve practical feasibility of these technologies. Some novel concepts for degrading PCs using integrated processes and genetic modifications to realize algal-based bioremediation technologies are also recommended. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Microalgae: a novel ingredient in nutrition.

    Science.gov (United States)

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

    2011-12-01

    Microalgae are known for centuries, but their commercial large-scale production started a few decades ago. They can be grown in open-culture systems such as lakes or highly controlled close-culture systems, have higher productivity than the traditional crops and can be grown in climatic conditions and regions where other crops cannot be grown, such as desert and coastal areas. The edible microalgae are the green algae (chlorophyta) and the cyanobacteria. Microalgae contain substances of high biological value, such as polyunsaturated fatty acids, proteins, amino acids, pigments, antioxidants, vitamins and minerals. They are promising sources for novel products and applications and they can be used in the diet of humans and animals as natural foods with health benefits. Moreover, they can find use in the protection of the environment, as well as in pharmaceuticals, biofuel production and cosmetics.

  1. Global evaluation of biofuel potential from microalgae

    Science.gov (United States)

    Moody, Jeffrey W.; McGinty, Christopher M.; Quinn, Jason C.

    2014-01-01

    In the current literature, the life cycle, technoeconomic, and resource assessments of microalgae-based biofuel production systems have relied on growth models extrapolated from laboratory-scale data, leading to a large uncertainty in results. This type of simplistic growth modeling overestimates productivity potential and fails to incorporate biological effects, geographical location, or cultivation architecture. This study uses a large-scale, validated, outdoor photobioreactor microalgae growth model based on 21 reactor- and species-specific inputs to model the growth of Nannochloropsis. This model accurately accounts for biological effects such as nutrient uptake, respiration, and temperature and uses hourly historical meteorological data to determine the current global productivity potential. Global maps of the current near-term microalgae lipid and biomass productivity were generated based on the results of annual simulations at 4,388 global locations. Maximum annual average lipid yields between 24 and 27 m3·ha−1·y−1, corresponding to biomass yields of 13 to 15 g·m−2·d−1, are possible in Australia, Brazil, Colombia, Egypt, Ethiopia, India, Kenya, and Saudi Arabia. The microalgae lipid productivity results of this study were integrated with geography-specific fuel consumption and land availability data to perform a scalability assessment. Results highlight the promising potential of microalgae-based biofuels compared with traditional terrestrial feedstocks. When water, nutrients, and CO2 are not limiting, many regions can potentially meet significant fractions of their transportation fuel requirements through microalgae production, without land resource restriction. Discussion focuses on sensitivity of monthly variability in lipid production compared with annual average yields, effects of temperature on productivity, and a comparison of results with previous published modeling assumptions. PMID:24912176

  2. Global evaluation of biofuel potential from microalgae.

    Science.gov (United States)

    Moody, Jeffrey W; McGinty, Christopher M; Quinn, Jason C

    2014-06-10

    In the current literature, the life cycle, technoeconomic, and resource assessments of microalgae-based biofuel production systems have relied on growth models extrapolated from laboratory-scale data, leading to a large uncertainty in results. This type of simplistic growth modeling overestimates productivity potential and fails to incorporate biological effects, geographical location, or cultivation architecture. This study uses a large-scale, validated, outdoor photobioreactor microalgae growth model based on 21 reactor- and species-specific inputs to model the growth of Nannochloropsis. This model accurately accounts for biological effects such as nutrient uptake, respiration, and temperature and uses hourly historical meteorological data to determine the current global productivity potential. Global maps of the current near-term microalgae lipid and biomass productivity were generated based on the results of annual simulations at 4,388 global locations. Maximum annual average lipid yields between 24 and 27 m(3)·ha(-1)·y(-1), corresponding to biomass yields of 13 to 15 g·m(-2)·d(-1), are possible in Australia, Brazil, Colombia, Egypt, Ethiopia, India, Kenya, and Saudi Arabia. The microalgae lipid productivity results of this study were integrated with geography-specific fuel consumption and land availability data to perform a scalability assessment. Results highlight the promising potential of microalgae-based biofuels compared with traditional terrestrial feedstocks. When water, nutrients, and CO2 are not limiting, many regions can potentially meet significant fractions of their transportation fuel requirements through microalgae production, without land resource restriction. Discussion focuses on sensitivity of monthly variability in lipid production compared with annual average yields, effects of temperature on productivity, and a comparison of results with previous published modeling assumptions.

  3. MICROALGAS E SEU POTENCIAL DE USO

    OpenAIRE

    Barcellos, Amanda Desireux; UFBA; Barreto, Antonio Geraldo da Silva Sá; UFBA; Machado, Bruna Aparecida Souza; UFBA; Druzian, Janice Izabel; UFBA

    2014-01-01

    As microalgas são organismos predominantemente microscópicos unicelulares, procariontes ou eucariontes, dotados de pigmentos e fotoautotróficos. Estes seres possuem um alto potencial biológico, ecológico e econômico. O objetivo desta prospecção tecnológica foi identificar as patentes, teses e artigos científicos referentes a microalgas quanto ao seu emprego nos mais diversos setores, bem como sua tecnologia de cultivo. Para tanto, foi realizada uma pesquisa aos bancos de dados de patentes nac...

  4. Nutrient recycle from defatted microalgae (Aurantiochytrium) with hydrothermal treatment for microalgae cultivation.

    Science.gov (United States)

    Aida, Taku Michael; Maruta, Ryouma; Tanabe, Yuuhiko; Oshima, Minori; Nonaka, Toshiyuki; Kujiraoka, Hiroki; Kumagai, Yasuaki; Ota, Masaki; Suzuki, Iwane; Watanabe, Makoto M; Inomata, Hiroshi; Smith, Richard L

    2017-03-01

    Defatted heterotrophic microalgae (Aurantiochytrium limacinum SR21) was treated with high temperature water (175-350°C, 10-90min) to obtain nitrogen and phosphorous nutrients as a water soluble fraction (WS). Yields of nitrogen and phosphorous recovered in WS varied from 38 to 100% and from 57 to 99%, respectively. Maximum yields of nitrogen containing compounds in WS were proteins (43%), amino acids (12%) and ammonia (60%) at treatment temperatures of 175, 250 and 350°C, respectively. Maximum yield of phosphorous in WS was 99% at a treatment temperature of 250°C. Cultivation experiments of microalgae (A. limacinum SR21) using WS obtained at 200 and 250°C showed positive growth. Water soluble fractions from hydrothermal treatment of defatted microalgae are effective nitrogen and phosphorous nutrient sources for microalgae cultivation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Culture of microalgae biomass for valorization of table olive processing water

    Directory of Open Access Journals (Sweden)

    Contreras, C. G.

    2016-09-01

    Full Text Available Table olive processing water (TOPW contains many complex substances, such as phenols, which could be valorized as a substrate for microalgae biomass culture. The aim of this study was to assess the capability of Nannochloropsis gaditana to grow in TOPW at different concentrations (10- 80% in order to valorize this processing water. Within this range, the highest increment of biomass was determined at percentage of 40% of TOPW, reaching an increment of 0.36 ± 0.05 mg volatile suspended solids (VSS/L. Components of algal biomass were similar for the experiments at 10-40% of TOPW, where proteins were the major compounds (56-74%. Total phenols were retained in the microalgae biomass (0.020 ± 0.002 g of total phenols/g VSS. Experiments for 80% of TOPW resulted in a low production of microalgae biomass. High organic matter, nitrogen, phosphorus and phenol removal were achieved in all TOPW concentrations. Although high-value products, such as proteins, were obtained and high removal efficiencies of nutrients were determined, microalgae biomass culture should be enhanced to become a suitable integral processing water treatment.El agua resultante del proceso de elaboración de la aceituna de mesa (TOPW presenta un elevado contenido en sustancias complejas, como fenoles, que podría permitir su uso como sustrato para el cultivo de microalgas. El objetivo de este estudio se centra en evaluar la capacidad de crecimiento de Nannochloropsis gaditana en TOPW a distintas concentraciones (10-80% con vistas a la valorización de estas aguas. El mayor incremento de biomasa se obtuvo para un porcentaje del 40% de TOPW, alcanzando un aumento de 0.36 ± 0.50 mg sólidos en suspensión volátiles (SSV/L. Los componentes presentes en la biomasa han sido similares para los experimentos con 10-40% de TOPW, siendo las proteínas los compuestos mayoritarios en todos los casos (56-74%. Los fenoles totales quedaron retenidos en las microalgas, alcanzando una concentraci

  6. Fatty Acid Content of Indonesian Aquatic Microalgae

    Directory of Open Access Journals (Sweden)

    TRI PRARTONO

    2010-12-01

    Full Text Available High utilization of fossil fuel increases the level of carbon dioxide in the atmosphere and results in global warming phenomenon. These things establish the world's thought to look for the other alternative energy that can reduce the use of fossil fuel even to be replaced by the substitute. Recently, Indonesia has been doing the research of microalgae as a feedstock of an alternative biofuel. Fatty acid content that microalgae have is also high to produce biofuel. The steps used in this research is a 7 days cultivation, harvesting, extraction using hexane, and fatty acid identification using Gas Chromatography of microalgae species. Fatty acid component in some species such as Chlorella sp., Scenedesmus sp., Nannochloropsis sp., and Isochrysis sp. is between 0.21-29.5%; 0.11-25.16%; 0.30-42.32%; 2.06-37.63%, respectively, based on dry weight calculation. The high content of fatty acid in some species of microalgae showed the potential to be the feedstock of producing biofuel in overcoming the limited utilization from petroleum (fossil fuel presently.

  7. Fatty Acid Content of Indonesian Aquatic Microalgae

    Directory of Open Access Journals (Sweden)

    TRI PRARTONO

    2010-12-01

    Full Text Available High utilization of fossil fuel increases the level of carbon dioxide in the atmosphere and results in global warming phenomenon. These things establish the world’s thought to look for the other alternative energy that can reduce the use of fossil fuel even to be replaced by the substitute. Recently, Indonesia has been doing the research of microalgae as a feedstock of an alternative biofuel. Fatty acid content that microalgae have is also high to produce biofuel. The steps used in this research is a 7 days cultivation, harvesting, extraction using hexane, and fatty acid identification using Gas Chromatography of microalgae species. Fatty acid component in some species such as Chlorella sp., Scenedesmus sp., Nannochloropsis sp., and Isochrysis sp. is between 0.21-29.5%; 0.11-25.16%; 0.30-42.32%; 2.06-37.63%, respectively, based on dry weight calculation. The high content of fatty acid in some species of microalgae showed the potential to be the feedstock of producing biofuel in overcoming the limited utilization from petroleum (fossil fuel presently.

  8. Production of structured triacylglycerols from microalgae

    Czech Academy of Sciences Publication Activity Database

    Řezanka, Tomáš; Lukavský, Jaromír; Nedbalová, Linda; Sigler, Karel

    2014-01-01

    Roč. 104, AUG 2014 (2014), s. 95-104 ISSN 0031-9422 R&D Projects: GA ČR(CZ) GAP503/11/0215 Institutional support: RVO:61388971 ; RVO:67985939 Keywords : microalgae * enantiomers * chiral LC Subject RIV: EE - Microbiology, Virology Impact factor: 2.547, year: 2014

  9. Negative effects of Phaeocystis globosa on microalgae

    NARCIS (Netherlands)

    Liu Jiesheng, [No Value; Van Rijssel, Marion; Yang Weidong, [No Value; Peng Xichun, [No Value; Lue Songhui, [No Value; Wang Yan, [No Value; Chen Jufang, [No Value; Wang Zhaohui, [No Value; Qi Yuzao, [No Value

    The potential allelopathic effects of the microalga, Phaeocystis globosa Scherffel, on three harmful bloom algae, Prorocentrum donghaiense Lu, Chattonella marina (Subrahmanyan) Hara et Chihara and Chattonella ovata Hara et Chihara were studied. The growth of C. marina and C. ovata was markedly

  10. Secondary wastewater treatment by microalgae isolated from ...

    African Journals Online (AJOL)

    Microalgae play a fundamental role in primary and secondary wastewater treatment. In this work the growth, photosynthetic activity and removal of phosphorus from wastewater effluents by indigenous blue-green algal species, Spirulina and Oscillatoria, isolated from Gaborone oxidation ponds was studied. Oscillatoria and ...

  11. Hydrothermal Liquefaction of the Microalgae Phaeodactylum tricornutum

    DEFF Research Database (Denmark)

    Sigaard Christensen, Per; Peng, Gaël; Vogel, Frédéric

    2014-01-01

    The microalgae Phaeodactylum tricornutum was processed by hydrothermal liquefaction in order to assess the influence of reaction temperature and reaction time on the product and elemental distribution. The experiments were carried out at different reaction times (5 and 15 min) and over a wide range...

  12. Physicochemical analysis of cellulose from microalgae ...

    African Journals Online (AJOL)

    ... cellulose of microalgae for the vegetal cellulose, as seen in the simple technical extraction, the yield and the procurement of uncontaminated molecule with lignin. This substitution will contribute in protecting the environment. Keywords: Cellulose, Nannochloropsis gaditana, procedure extraction, structural characterization ...

  13. Investigation of microalgae with photon density waves

    Science.gov (United States)

    Frankovitch, Christine; Reich, Oliver; Löhmannsröben, Hans-Gerd

    2007-09-01

    Phototropic microalgae have a large potential for producing valuable substances for the feed, food, cosmetics, pigment, bioremediation, and pharmacy industries as well as for biotechnological processes. Today it is estimated that the microalgal aquaculture worldwide production is 5000 tons of dry matter per year (not taking into account processed products) making it an approximately $1.25 billion U.S. per year industry. For effective observation of the photosynthetic growth processes, fast on-line sensor systems that analyze the relevant biological and technical process parameters are preferred. The optical properties of the microalgae culture influence the transport of light in the photobioreactor and can be used to extract relevant information for efficient cultivation practices. Microalgae cultivation media show a combination of light absorption and scattering, which are influenced by the concentrations and the physical and chemical properties of the different absorbing and scattering species (e.g. pigments, cell components, etc.). Investigations with frequency domain photon density waves (PDW) allow for the examination of absorption and scattering properties of turbid media, namely the absorption and reduced scattering coefficient. The reduced scattering coefficient can be used to characterize physical and morphological properties of the medium, including the cell concentration, whereas the absorption coefficient correlates with the pigment content. Nannochloropsis oculata, a single-cell species of microalgae, were examined in a nutrient solution with photon density waves. The absorption and reduced scattering coefficients were experimentally determined throughout the cultivation process, and applied to gain information about the cell concentration and average cell radius.

  14. Microalgae growth on concentrated human urine

    NARCIS (Netherlands)

    Tuantet, K.; Janssen, M.G.J.; Temmink, H.; Zeeman, G.; Wijffels, R.H.; Buisman, C.J.N.

    2014-01-01

    In this study, for the first time, a microalga was grown on non-diluted human urine. The essential growth requirements for the species Chlorella sorokiniana were determined for different types of human urine (fresh, hydrolysed, male and female). Batch experimental results using microtiter plates

  15. Towards high productivities of microalgae in photobioreactors

    NARCIS (Netherlands)

    Bosma, R.

    2010-01-01

    The biodiversity of microalgae is enormous and they represent an almost untapped source of unique algae products. Presently, there is a niche market for high-value algal products (e.g. carotenoids and fatty acids). To make commercial production of low-value bulk products possible, still many

  16. Antenna size reduction in microalgae mass culture

    NARCIS (Netherlands)

    Mooij, de T.

    2016-01-01

    The thesis describes the potential of microalgae with a reduced light harvesting antenna for biomass production under mass culture conditions (high biomass density, high light intensity). Theoretically, the lower chlorophyll content reduces the light harvesting capacity and with that the amount

  17. Harvesting microalgae with microwave synthesized magnetic microparticles

    Czech Academy of Sciences Publication Activity Database

    Procházková, G.; Šafařík, Ivo; Brányik, T.

    2013-01-01

    Roč. 130, FEB (2013), s. 472-477 ISSN 0960-8524 R&D Projects: GA MŠk LH12190 Institutional support: RVO:67179843 Keywords : harvesting microalgae * iron oxide magnetic microparticles * non-covalent interactions * microwave treatment * cell demagnetization Subject RIV: EI - Biotechnology ; Bionics Impact factor: 5.039, year: 2013

  18. hydroprocessing processing processing microalgae derived h

    African Journals Online (AJOL)

    eobe

    convert the whole biomass into primarily liquid product (the bio-crude); and two other products – some gases .... replacement for co-firing with coal [2]. The upgrade however, makes the bio-crude a good candidate ... microalgae biomass to liquid fuels via HTL and HDT,. Jones et al., [39] employed CoMo/alumina-F catalyst.

  19. Efecto de metales pesados en el crecimiento de la microalga tropical Tetraselmis chuii (Prasinophyceae

    Directory of Open Access Journals (Sweden)

    Jiudith Cordero

    2005-09-01

    Full Text Available El presente trabajo determina el efecto tóxico de los metales cadmio (Cd, cobre (Cu, mercurio (Hg y plomo (Pb en la microalga tropical Tetraselmis chuii (Butcher, 1959. Se expuso, por triplicado, 50 ml de cultivo (f/2 Guillard de la microalga en fase de crecimiento logarítmica ante las concentraciones de 0 (control; 0.1; 1.0; 5.0; 10.0 y 20.0 mg· l-1 durante 96 hr. La evaluación del efecto letal se realizó diariamente, mediante recuento celular con una cámara de Neubauer. En el tratamiento control, sin exposición al metal, se observó un incremento de la densidad celular, en contraste con un decrecimiento en los tratamientos con exposición a los metales, los cuales fueron acelerados hasta las 48 hr, a partir de cuando el decrecimiento se hizo menos pronunciado. Una excepción se produjo con el Cd y el Cu a las 24 h, donde no se determinó decrecimiento significativo, probablemente debido a su capacidad de actuar como micronutriente a bajas concentraciones. El metal que produjo mayor efecto fue el Pb, produciendo una letalidad al 50% de la población microalgal a 0.40 mg· l-1, la cual fue casi tres veces menor que la establecida para el Hg y más de 13 veces menor que la del Cd y Cu. Se recomienda la microalga Tetraselmis chuii como especie modelo para la utilización en pruebas en función estimar efectos tóxicos por xenobióticos en el ambiente acuático marino tropical.Efect of heavy metals on the growth of the tropical microalga Tetrasermis chuii (Prasinophyceae. We determined the toxic effect of four metals, cadmium (Cd, copper (Cu, mercury (Hg and lead (Pb, on the tropical microalga Tetraselmis Chuii (Butcher, 1959. We exposed 50 ml of cultivated microalgae (f/2 Guillard in the exponential growth phase, with three replicates, to concentrations of 0 (control, 0.1, 1.0, 5.0, 10.0 and 20.0 mg· l-1 with each metal for 96 hr. We evaluated the lethal effect daily, through the cellular count. In the control treatment (not exposed to any

  20. Microalgae harvesting and processing: a literature review

    Energy Technology Data Exchange (ETDEWEB)

    Shelef, G.; Sukenik, A.; Green, M.

    1984-08-01

    The objective of this report is to present a discussion of the literature review performed on methods of harvesting microalgae. There is no single best method of harvesting microalgae. The choice of preferable harvesting technology depends on algae species, growth medium, algae production, end product, and production cost benefit. Algae size is an important factor since low-cost filtration procedures are presently applicable only for harvesting fairly large microalgae. Small microalgae should be flocculated into larger bodies that can be harvested by one of the methods mentioned above. However, the cells' mobility affects the flocculation process, and addition of nonresidual oxidants to stop the mobility should be considered to aid flocculation. The decision between sedimentation or flotation methods depends on the density difference between the algae cell and the growth medium. For oil-laden algae with low cell density, flotation technologies should be considered. Moreover, oxygen release from algae cells and oxygen supersaturation conditions in growth medium support the use of flotation methods. If high-quality algae are to be produced for human consumption, continuous harvesting by solid ejecting or nozzle-type disc centrifuges is recommended. These centrifuges can easily be cleaned and sterilized. They are suitable for all types of microalgae, but their high operating costs should be compared with the benefits from their use. Another basic criterion for selecting the suitable harvesting procedure is the final algae paste concentration required for the next process. Solids requirements up to 30% can be attained by established dewatering processes. For more concentrated solids, drying methods are required. The various systems for algae drying differ both in the extent of capital investment and the energy requirements. Selection of the drying method depends on the scale of operation and the use for which the dried product is intended.

  1. Crecimiento en jaulas del pargo lunarejo Lutjanus guttatus (Steindachner, 1869 con dos tipos de dieta en Bahía Málaga, municipio de Buenaventura, Colombia

    Directory of Open Access Journals (Sweden)

    Edgardo Andrés Banguera Gil

    2010-01-01

    Full Text Available Para dar continuidad al “Programa de desarrollo de la maricultura en el Pacífico colombiano” adelantado por la Universidad del Pacífico, en un cerramiento natural ubicado en la vereda La Sierpe, Bahía Málaga, municipio de Buenaventura, se comparó la tasa de crecimiento de 204 ejemplares silvestres de pargo lunarejo Lutjanus guttatus , alimentados con pescado fresco y concentrado comercial al 35% en proteína, con peso y longitud total promedio de 13,79 cm y 32,21 g, respectivamente. El trabajo se realizó por espacio de 40 días en cuatro jaulas flotantes, de 3 x 1,5 x 0,75 m, dos para cada tratamiento, a densidades de 15 individuos/m 3 , utilizando el 12% de la biomasa corporal para el suministro de los alimentos a evaluar; el crecimiento se analizó mediante los siguientes índices: IPD = Incremento en Peso Diario; TCE = Tasa de Crecimiento Específico. Los peces alcanzaron un peso promedio final de 64,9±5,9 y 58,49±5,9 g para el alimento natural y balanceado comercial respectivamente, lo cual es equivalente a un IPD de 0.8 y 0.7 g/d y una TCE de 1,58 y 1,67 g/d, valores considerados buenos teniendo en cuenta su etapa de desarrollo y comparaciones con otros estudios realizados en Colombia. Los peces aceptaron los dos tipos de alimento de manera satisfactoria, durante el período de cultivo y mostraron gran tolerancia a la manipulación, resistencia a las enfermedades y a las fluctuaciones de la calidad del agua, en especial la salinidad. Los resultados señalan que existen diferencias significativas (P>0.05 entre los dos tratamientos a favor del alimento natural. Los índices de sobrevivencia fueron de 90,2% para peces alimentados con pescado fresco y 85,3% para los alimentados con concentrado. Se concluye que el pargo lunarejo Lutjanus guttatus presenta una importante ventaja para su cultivo como es la fácil aceptación de un concentrado comercial. pero el crecimiento de los peces alimentados con este producto fue

  2. Microalgae as a safe food source for animals: nutritional characteristics of the acidophilic microalga Coccomyxa onubensis

    Directory of Open Access Journals (Sweden)

    Francisco Navarro

    2016-10-01

    Full Text Available Background: Edible microalgae are marine or fresh water mesophilic species. Although the harvesting of microalgae offers an abundance of opportunities to the food and pharmaceutical industries, the possibility to use extremophilic microalgae as a food source for animals is not well-documented. Objective: We studied the effects of dietary supplementation of a powdered form of the acidophilic microalga Coccomyxa onubensis on growth and health parameters of laboratory rats. Method: Four randomly organized groups of rats (n=6 were fed a standard diet (Diet 1, control or with a diet in which 0.4% (Diet 2, 1.25% (Diet 3, or 6.25% (Diet 4 (w/w of the standard diet weight was substituted with dried microalgae powder, respectively. The four groups of animals were provided ad libitum access to feed for 45 days. Results: C. onubensis biomass is rich in protein (44.60% of dry weight and dietary fiber (15.73%, and has a moderate carbohydrate content (24.8% and a low lipid content (5.4% in which polyunsaturated fatty acids represent 65% of the total fatty acid. Nucleic acids are present at 4.8%. No significant difference was found in growth rates or feed efficiency ratios of the four groups of rats. Histological studies of liver and kidney tissue revealed healthy organs in control and C. onubensis-fed animals, while plasma hematological and biochemical parameters were within healthy ranges for all animals. Furthermore, animals fed a microalgae-enriched diet exhibited a statistically significant decrease in both blood cholesterol and triglyceride levels. The blood triglyceride content and very low density lipoprotein-cholesterol levels decreased by about 50% in rats fed Diet 4. Conclusions: These data suggest that C. onubensis may be useful as a food supplement for laboratory animals and may also serve as a nutraceutical in functional foods. In addition, microalgae powder-supplemented diets exerted a significant hypocholesterolemic and hypotriglyceridemic

  3. Evaluation of the Antioxidant Activity of Cell Extracts from Microalgae

    OpenAIRE

    F. Xavier Malcata; Pedro Moradas-Ferreira; Paula Tamagnini; A. C. Silva Ferreira; Maria S. Gião; Rui Seabra; A. Catarina Guedes

    2013-01-01

    A growing market for novel antioxidants obtained from non-expensive sources justifies educated screening of microalgae for their potential antioxidant features. Characterization of the antioxidant profile of 18 species of cyanobacteria (prokaryotic microalgae) and 23 species of (eukaryotic) microalgae is accordingly reported in this paper. The total antioxidant capacity, accounted for by both water- and lipid-soluble antioxidants, was evaluated by the (radical cation) ABTS method. For complem...

  4. EVALUACIÓN DE PARÁMETROS PRODUCTIVOS Y PIGMENTACIÓN EN POLLOS ALIMENTADOS CON HARINA ZAPALLO (Cucurbita moschata

    Directory of Open Access Journals (Sweden)

    JULIANA CARVAJAL TAPIA

    2017-12-01

    Full Text Available On the farms you can get different products from small farming system that can contribute to the economy of the poultyman farmer, for example, the squash (Cucurbita moschata. With the squash flour was evaluated pigmentation of skin and productive parameters in broilers. With the inclusion of 0, 7,5 and 15 percent in diets. A design completely at random (DCA was used with four repetitions and four animals per experimental unit. The analysis of variety did not show statistic differences (p≤0,05 for the feed intake in the two phases, either in weight gain and feed conversion in the ending phase; there were showed meaningful statistic differences for weight gain and feed conversion in the starter phase and the pigmentation in the final phase, the skin pigmentation of animals fed with squash flour was intense yellow according to the variety of colors DMS compared to those fed with the witness treatment. The inclusion of squash flour in diets for feeding broiler chicken bigger than 7,5% y less than 15%, is considered as a no conventional raw material that helps to the pigmentation of the skin, without affecting productive parameters in the ending phase and it becomes in an alternative for the productive systems of the small producers generating a value added in terms of skin pigmentation.

  5. Análisis y modelado del generador de inducción doblemente alimentado. Analysis and Modeling of Doubly Fed Induction Generators.

    Directory of Open Access Journals (Sweden)

    Lesyani T. León Viltre

    2015-04-01

    Full Text Available Uno de los generadores eólicos de velocidad variable más utilizados en la actualidad es el generador de inducción doblemente alimentado (DFIG. En el presente trabajo se presenta un esquema de control del DFIG. El convertidor de potencia del lado de la red es modelado y controlado usando el vector de tensión orientado a los ejes dq, lo que garantiza que con la componente del eje d de la corriente se pueda controlar la potencia activa y, por consiguiente, la tensión del bus DC. La componente del eje q es forzada a cero para mantener un factor de potencia unitario. En el convertidor del lado del rotor se utiliza un control orientado al flujo del estator. Para la sincronización con la red se utiliza un método novedoso basado en el método GDSC-PLL (Generalizad delayed signal cancellation. Además, se presenta un análisis del comportamiento del DFIG, ante huecos de tensión.  One of the variable speed wind turbines most commonly used today is the doubly feed induction generator(DFIG.A control scheme of DFIG is discussed in this paper. The power converter connected to the grid side (bus is modeled and controlled using voltage vectororiented dq reference frame, whichguarantees that the active power can be controlled by the daxiscurrent component and consequently the DC bus voltage. The qaxis component is forced to be zero in order to ensurethe unitary power factor. Astator flux oriented control in the rotor circuit converter is used.A novel GDSC-PLL method is used in order to achieve an efficient synchronization with the grid.Onthe order hand, this paper presents an analysis about the DFIG (Double Feed Induction Generator behavior during voltages sags.

  6. Análisis y modelado del generador de inducción doblemente alimentado; Analysis and Modeling of Doubly Fed Induction Generators

    Directory of Open Access Journals (Sweden)

    Lesyani T- León Viltre

    2014-06-01

    Full Text Available Uno de los generadores eólicos de velocidad variable más utilizados en la actualidad es el generador de inducción doblemente alimentado (DFIG. En el presente trabajo se presenta un esquema de control del DFIG. El convertidor de potencia del lado de la red es modelado y controlado usando el vector de tensión orientado a los ejes dq, lo que garantiza que con la componente del eje d de la corriente se pueda controlar la potencia activa y, por consiguiente, la tensión del bus DC. La componente del eje q es forzada a cero para mantener un factor de potencia unitario. En el convertidor del lado del rotor se utiliza un control orientado al flujo del estator. Para la sincronización con la red se utiliza un método novedoso basado en el método GDSC-PLL (Generalizad delayed signal cancellation. Además, se presenta un análisis del comportamiento del DFIG, ante huecos de tensión. One of the variable speed wind turbines most commonly used today is the doubly feed induction generator(DFIG.A control scheme of DFIG is discussed in this paper. The power converter connected to the grid side (bus is modeled and controlled using voltage vectororiented dq reference frame, whichguarantees that the active power can be controlled by the daxiscurrent component and consequently the DC bus voltage. The qaxis component is forced to be zero in order to ensurethe unitary power factor. Astator flux oriented control in the rotor circuit converter is used.A novel GDSC-PLL method is used in order to achieve an efficient synchronization with the grid.Onthe order hand, this paper presents an analysis about the DFIG (Double Feed Induction Generator behavior during voltages sags

  7. Overcoming Microalgae Harvesting Barrier by Activated Algae Granules.

    Science.gov (United States)

    Tiron, Olga; Bumbac, Costel; Manea, Elena; Stefanescu, Mihai; Nita Lazar, Mihai

    2017-07-05

    The economic factor of the microalgae harvesting step acts as a barrier to scaling up microalgae-based technology designed for wastewater treatment. In view of that, this study presents an alternative microalgae-bacteria system, which is proposed for eliminating the economic obstacle. Instead of the microalgae-bacteria (activated algae) flocs, the study aimed to develop activated algae granules comprising the microalgae Chlorella sp. as a target species. The presence of the filamentous microalgae (Phormidium sp.) was necessary for the occurrence of the granulation processes. A progressive decrease in frequency of the free Chlorella sp. cells was achieved once with the development of the activated algae granules as a result of the target microalgae being captured in the dense and tangled network of filaments. The mature activated algae granules ranged between 600 and 2,000 µm, and were characterized by a compact structure and significant settling ability (21.6 ± 0.9 m/h). In relation to the main aim of this study, a microalgae recovery efficiency of higher than 99% was achieved only by fast sedimentation of the granules; this performance highlighted the viability of the granular activated algae system for sustaining a microalgae harvesting procedure with neither cost nor energy inputs.

  8. Learning sustainability by developing a solar dryer for microalgae retrieval

    Directory of Open Access Journals (Sweden)

    Benedita Malheiro

    2016-01-01

    Full Text Available Excessive fossil fuel consumption is driving the search for alternative energy production solutions and, in particular, for sustainable sources of energy such as microalgae, from which biodiesel, among other useful compounds, can be obtained. After producing the microalgae, they must be harvested and dried. Existing drying solutions consume too much energy and are, therefore, expensive and unsustainable. The goal of this EPS@ISEP Spring 2013 project was to develop a solar microalgae dryer for the microalgae laboratory of ISEP. A multinational team of five students from distinct fields of study was responsible for designing and building the solar microalgae dryer prototype. The prototype includes a control system to ensure that the microalgae are not destroyed during the drying process. The solar microalgae dryer works as a distiller, extracting the excess water from the microalgae suspension. This paper details the design steps, the building technologies, the ethical and sustainable concerns and compares the prototype with existing solutions. The proposed sustainable microalgae drying process is competitive as far as energy usage is concerned. Finally, the project contributed to increase the team’s sustainable development awareness, active learning and motivation.

  9. Lipid extraction from microalgae using a single ionic liquid

    Science.gov (United States)

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

    2013-05-28

    A one-step process for the lysis of microalgae cell walls and separation of the cellular lipids for use in biofuel production by utilizing a hydrophilic ionic liquid, 1-butyl-3-methylimidazolium. The hydrophilic ionic liquid both lyses the microalgae cell walls and forms two immiscible layers, one of which consists of the lipid contents of the lysed cells. After mixture of the hydrophilic ionic liquid with a suspension of microalgae cells, gravity causes a hydrophobic lipid phase to move to a top phase where it is removed from the mixture and purified. The hydrophilic ionic liquid is recycled to lyse new microalgae suspensions.

  10. Removal of freshwater microalgae by a magnetic separation method

    Science.gov (United States)

    Vergini, Sofia S.; Aravantinou, Andriana F.; Manariotis, Ioannis D.

    2013-04-01

    Some species of microalgae, with high growth rate and high lipid content, appear to be attractive alternatives as a feedstock for biodiesel production. The high-energy input for harvesting biomass and removing the water from the algae makes current commercial microalgal biodiesel production cost expensive. The major techniques currently employed in microalgae harvesting and recovery include centrifugation, coagulation-flocculation, bio-flocculation, filtration and screening, gravity sedimentation, and flotation. The purpose of this study was to investigate the harvesting of microalgae cells by coagulation using magnetic activated carbon, magnetite (FeO4) nanoparticles, and common chemical coagulants. Scenedesmus rubescens was selected and cultivated in 10 L flasks under continuous artificial light. Samples were taken at different operation intervals. Jar tests were conducted to investigate the effect of adsorption of microalgae on the magnetic material. The removal efficiency of microalgae was affected by the coagulants dose, stirring time and speed, and the initial microalgae concentration. The recovery of microalgae was greater in cultures with high initial microalgae concentration compared to cultures with low microalgae concentrations.

  11. Microalgae: cultivation techniques and wastewater phycoremediation.

    Science.gov (United States)

    Pacheco, Marcondes M; Hoeltz, Michele; Moraes, Maria S A; Schneider, Rosana C S

    2015-01-01

    Generation of liquid and gaseous effluents is associated with almost all anthropogenic activities. The discharge of these effluents into the environment without treatment has reduced the availability and quality of natural resources, representing a serious threat to the balance of different ecosystems and human health. Universal access to water and global warming are topics of intense concern and are listed as priorities in the vast majority of global scientific, social and political guidelines. Conventional techniques to treat liquid and gaseous effluents pose economic and/or environmental limitations that prevent their use in certain applications. The technique of phycoremediation, which uses microalgae, macroalgae, and cyanobacteria for the removal or biotransformation of pollutants, is an emerging technology that has been highlighted due to its economic viability and environmental sustainability. This literature review discusses different techniques of microalgae cultivation and their use in the phycoremediation of contaminants in wastewater.

  12. Microalgae for Biofuels and Animal Feeds

    Directory of Open Access Journals (Sweden)

    John Benemann

    2013-11-01

    Full Text Available The potential of microalgae biomass production for low-cost commodities—biofuels and animal feeds—using sunlight and CO2 is reviewed. Microalgae are currently cultivated in relatively small-scale systems, mainly for high value human nutritional products. For commodities, production costs must be decreased by an order of magnitude, and high productivity algal strains must be developed that can be stably cultivated in large open ponds and harvested by low-cost processes. For animal feeds, the algal biomass must be high in digestible protein and long-chain omega-3 fatty acids that can substitute for fish meal and fish oils. Biofuels will require a high content of vegetable oils (preferably triglycerides, hydrocarbons or fermentable carbohydrates. Many different cultivation systems, algal species, harvesting methods, and biomass processing technologies are being developed worldwide. However, only raceway-type open pond systems are suitable for the production of low-cost commodities.

  13. Energy from biomass production - photosynthesis of microalgae?

    Energy Technology Data Exchange (ETDEWEB)

    Lamparter, Tilman [Universitaet Karlsruhe, Botanisches Institut, Geb. 10.40, Kaiserstr. 2, D-76131 Karlsruhe (Germany)

    2009-07-01

    The composition of our atmosphere in the past, present and future is largely determined by photosynthetic activity. Other biological processes such as respiration consume oxygen and produce, like the use of the limited fossil fuel resources, CO{sub 2} whose increasing atmospheric concentration is a major concern. There is thus a demand on the development of alternative energy sources that replace fossil fuel. The use of crop plants for the production of biofuel is one step towards this direction. Since most often the same areas are used as for the production of food, the increased production of biofuel imposes secondary problems, however. In this context, the use of microalgae for biomass production has been proposed. Not only algae in the botanical sense (lower plants, photosynthetic eukaryotes) but also cyanobacteria, which belong to the prokaryotes, are used as ''microalgae''. The conversion of light energy into biomass can reach much higher efficiencies than in crop plants, in which a great portion of photosynthesis products is used to build up non-photosynthetic tissues such as roots or stems. Microalgae can grow in open ponds or bioreactors and can live on water of varying salinity. It has been proposed to grow microalgae in sea water on desert areas. Ongoing research projects aim at optimizing growth conditions in bioreactors, the recycling of CO{sub 2} from flue gases (e.g. from coal-fired power plants), the production of hydrogen, ethanol or lipids, and the production of valuable other substances such as carotenoids.

  14. Laboratory apparatus to evaluate microalgae production

    Directory of Open Access Journals (Sweden)

    L. R. S. Gris

    2013-09-01

    Full Text Available The application of microalgae for energy purposes and CO2 biomitigation continues to present a number of challenges, including the optimization of culture conditions. The application of experimental designs for microalgae cultivation is difficult, since experiments involving such microorganisms generally last days or weeks. This work proposes a multipurpose laboratory apparatus for the optimization of microalgae experimental conditions that simultaneously enables the evaluation of variables such as temperature, irradiance, photoperiod and CO2 concentration in the aeration stream, as well as variables related to the concentration of culture media nutrients. A case study is also presented in which temperature, concentration of f/2 medium sodium nitrate and the effects of incident light intensity on Nannochloropsis oculata lipid content are evaluated. Experiments were carried out following central composite designs, in batch cultivation within an airlift photobioreactor apparatus. The best experimental result was obtained at 21 ºC, 119 mg/L NaNO3 and 137 µE.m-2.s-1, corresponding to 41.8% lipids and 211.9 mg.L-1 final lipid concentrations.

  15. Applications of Imaging Flow Cytometry for Microalgae.

    Science.gov (United States)

    Hildebrand, Mark; Davis, Aubrey; Abbriano, Raffaela; Pugsley, Haley R; Traller, Jesse C; Smith, Sarah R; Shrestha, Roshan P; Cook, Orna; Sánchez-Alvarez, Eva L; Manandhar-Shrestha, Kalpana; Alderete, Benjamin

    2016-01-01

    The ability to image large numbers of cells at high resolution enhances flow cytometric analysis of cells and cell populations. In particular, the ability to image intracellular features adds a unique aspect to analyses, and can enable correlation between molecular phenomena resulting in alterations in cellular phenotype. Unicellular microalgae are amenable to high-throughput analysis to capture the diversity of cell types in natural samples, or diverse cellular responses in clonal populations, especially using imaging cytometry. Using examples from our laboratory, we review applications of imaging cytometry, specifically using an Amnis(®) ImageStream(®)X instrument, to characterize photosynthetic microalgae. Some of these examples highlight advantages of imaging flow cytometry for certain research objectives, but we also include examples that would not necessarily require imaging and could be performed on a conventional cytometer to demonstrate other concepts in cytometric evaluation of microalgae. We demonstrate the value of these approaches for (1) analysis of populations, (2) documentation of cellular features, and (3) analysis of gene expression.

  16. Evaluation on Microalgae Biomass for Bioethanol Production

    Science.gov (United States)

    Chng, L. M.; Lee, K. T.; Chan, D. C. J.

    2017-06-01

    The depletion of energy resources has triggered worldwide concern for alternative sources, especially renewable energy. Microalgae biomass offers the most promising feedstock for renewable energy because of their impressive efficient growing characteristics and valuable composition. Simple cell structure of the microalgae would simplify the pretreatment technology thus increase the cost-effectiveness of biofuel production. Scenedesmus dimorphus is a carbohydrate-rich microalgae that has potential as biomass for bioethanol. The cultivation of Scenedesmus dimorphus under aeration of carbon dioxide enriched air resulted 1.47 g/L of dry biomass with composition of 12 w/w total lipid, 53.7 w/w carbohydrate and 17.4 protein. Prior to ethanolic fermentation with Saccharomyces cerevisiae, various pre-treatment methods were investigated to release and degrade the complex carbohydrate in cell biomass thus obtaining the maximal amount of digestible sugar for ethanolic yeast. In this study, sulfuric acid was used as hydrolysis agent while amyloglucosidase as enzymatic agent. Dried biomass via hydrothermal acidic hydrolysis yielded sugar which is about 89 of total carbohydrate at reaction temperature of 125 °C and acid concentration of 4 v/v. While combination of organosolv treatment (mixture of methanol and chloroform) with enzymatic hydrolysis yielded comparable amount of sugar with 0.568 g glucose/g treated-biomass. In this study, the significant information in pre-treatment process ensures the sustainability of the biofuel produced.

  17. Production of biodiesel from Coelastrella sp. microalgae

    Science.gov (United States)

    Mansur, Dieni; Fitriady, Muhammad Arifuddin; Susilaningsih, Dwi; Simanungkalit, Sabar Pangihutan

    2017-11-01

    Microalgae have a wide area of usage and one of them it can be used for biodiesel production. In biodiesel production, lipids containing triglyceride or free fatty acid are converted into methyl ester through trans/esterification reactions. Lipids from microalgae can be extracted by acetone and dimethyl carbonate using homogenizer. Esterification of the lipids was investigated using various catalysts and source of methyl group. Activity of homogeneous catalyst such as HCl and H2SO4 and heterogeneous catalysts such as montmorillonit K-10 and ledgestone was investigated. Moreover, methanol and dimethyl carbonate as source of methyl group were also studied. Among of catalysts with methanol as source of methyl group, it was found that yield of crude biodiesel derived from Choelestrella Sp. microalgae was high over H2SO4 catalyst. On the other hand, over H2SO4 catalyst using dimethyl carbonate as source of methyl group, yield of crude biodiesel significant increase. However, FAME composition of crude biodiesel was high over HCl catalyst.

  18. Crescimento e metabolismo do nitrogênio em juvenis de Trachinotus marginatus alimentados com diferentes níveis proteicos

    Directory of Open Access Journals (Sweden)

    E.M. Silva

    2015-02-01

    Full Text Available O objetivo deste trabalho foi avaliar o crescimento e alterações no metabolismo do nitrogênio, além da composição do fígado e do músculo de juvenis de pampo Trachinotus marginatus alimentados com 43, 54 ou 64% de proteína bruta (PB43, PB54 e PB64, respectivamente. Grupos de 10 juvenis (1,47±0,14g foram estocados em nove tanques de 50L, em sistema de recirculação de água marinha, durante 55 dias, alimentados quatro vezes ao dia com as rações pré-definidas. O ganho em peso, a taxa de crescimento específico e a conversão alimentar não apresentaram diferença significativa (P>0,05. Contudo, o acréscimo de proteína consumida aumentou o índice hepatossomático e a taxa de excreção de amônia pós-prandial, bem como diminuiu a retenção proteica. Os peixes alimentados com a dieta PB43 apresentaram menor concentração da transaminase glutâmico oxalacética hepática, além de menor concentração de triglicerídeos no músculo e fígado (P0,05, excetuando o maior teor de lipídios da carcaça no tratamento PB43. Concluímos que a melhor utilização da proteína por juvenis de pampo é observada quando eles são alimentados com uma dieta contendo 43% de proteína.

  19. Efficient recovery of uranium using genetically improved microalgae; Recuperacion eficaz de uranio utilizando microalgas geneticamente mejoradas

    Energy Technology Data Exchange (ETDEWEB)

    Lopez-Rodas, V.; Conde Vilda, E.; Garcia-Balboa, C.

    2015-07-01

    We propose an alternative process for the efficient recovery of dissolved uranium based on genetically improved microalgae. We isolate Chlamydomonas cf. fonticola from a pond extremely contaminated by uranium (∼ 25 ppm) from ENUSA U-mine, Saelices (Salamanca, Spain). After a process of genetic improvement we obtained a strain capable to recover 115 mg of U per g of dry weight, by mean of bio-adsorption on the cell wall (mostly) and intra-cytoplasm bioaccumulation. Such a genetically improved microalgae resist extremes of acidity and pollution, but even its dead biomass is still able to recover a large amount of uranium. (Author)

  20. Desempenho e características de carcaça de cordeiros Suffolk alimentados com diferentes volumosos

    Directory of Open Access Journals (Sweden)

    Cunha Eduardo Antonio da

    2001-01-01

    Full Text Available Cordeiros da raça Suffolk, desmamados aos 60 dias e confinados, foram alimentados com silagem de milho, silagem de sorgo granífero ou feno de Coast cross (Cynodon dactylon L. Pears e ração concentrada (3,5% do peso vivo, com o objetivo de avaliar seu desempenho, a proporção dos componentes-não-carcaça e o rendimento e características das suas carcaças. Foi utilizado um delineamento completamente casualizado em esquema fatorial (três alimentos volumosos e dois sexos. Os animais alimentados com silagem de milho ou de sorgo mostraram maior (P0,05 pelo tipo de alimento, contudo, os animais alimentados com silagem de milho apresentaram carcaças com maior (P0,05 na proporção de músculos (60,0 e 60,7%. A silagem de sorgo pode substituir a silagem de milho para cordeiros confinados, contudo o uso do feno de gramínea reduz o seu desempenho.

  1. Caracterización y perfil lipídico de aceites de microalgas

    Directory of Open Access Journals (Sweden)

    Lesly Tejeda-Benítez

    2015-05-01

    Full Text Available El uso creciente del biodiésel ha impulsado la búsqueda de nuevas materias primas, dentro de las que se destacan las microalgas. En esta investigación se estudió el cultivo de las microalgas Chlorella sp. y Dunaliella salina bajo diferentes condiciones de pH y concentración de nitrógeno (mgL-1, y la caracterización de los aceites obtenidos, con el fin de evaluar su potencial uso como materia prima en la producción de biodiésel. La D. salina alcanzó una máxima concentración celular de 1.15x106 células mL-1 en 6 días de cultivo en unas condiciones de 8.5 pH y 0.1 mg L-1 concentración de nitrógeno, mientras que Chlorella sp. presentó una máxima concentración celular de 2.6x107 células mL-1 en 14 días de cultivo en unas condiciones de 7.5 pH y 0.1 mg L-1 concentración de nitrógeno. La extracción de aceite intracelular de las microalgas cultivadas bajo las mejores condiciones de crecimiento celular se realizó empleando el método modificado de Bligh & Dyer. Al determinar el perfil de ácidos grasos de los aceites extraídos de ambas microalgas, se  encontraron en mayor proporción dos ácidos grasos insaturados: ácido linolénico y ácido oleico. En el aceite de D. salina se encontró una concentración de 51% p/p de ácido linolénico, mientras que para el aceite de Chlorella sp. fue de 39% p/p. Con relación al ácido oleico, el aceite de Chrorella sp. presentó una concentración de 35% p/p, superior al aceite de D. salina, con 25% p/p.

  2. Cultivation of the microalga, Chlorella pyrenoidosa , in biogas ...

    African Journals Online (AJOL)

    Biogas wastewater is always a problem as a result of its extremely high concentrations of nitrogen and phosphorus, which is the main reason for the eutrophication of the surrounding water. The microalga, Chlorella pyrenoidosa, can utilize the nitrogen and phosphorus in wastewater for its growth. Therefore, the microalga ...

  3. Enzyme assisted protein extraction from rapeseed, soybean, and microalgae meals

    NARCIS (Netherlands)

    Sari, Y.W.; Bruins, M.E.; Sanders, J.P.M.

    2013-01-01

    Oilseed meals that are by-products from oil production are potential resources for protein. The aim of this work is to investigate the use of enzymes in assisting in the extraction of protein from different oilseed meals, namely rapeseed, soybean, and microalgae meals. In addition, microalgae

  4. Novel protocol for lutein extraction from microalga Chlorella vulgaris

    DEFF Research Database (Denmark)

    D'Este, Martina; De Francisci, Davide; Angelidaki, Irini

    2017-01-01

    Lutein is a pigment generally extracted from marigold flowers. However, lutein is also found in considerable amounts in microalgae. In this study a novel method was developed to improve the extraction efficiency of lutein from microalga C. vulgaris. Differently from conventional methods, ethanol...

  5. Prospective of biodiesel production utilizing microalgae as the cell ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-03-08

    Mar 8, 2010 ... unwanted microalgae and fungi, bacteria and protozoa that feed on algae. Recently, some work has ... discussion about the potential of microalgae for the production of valuable lipid compounds that can be further used for ... methane, sulfur dioxide and volatile organic compounds. (Gavrilescu and Chisti ...

  6. Response of microalgae from mud-flats to petroleum hydrocarbons ...

    African Journals Online (AJOL)

    SERVER

    2008-03-04

    Mar 4, 2008 ... Emphasis may be put on wastewater treat- ment and/or algae biomass production. ..... Figure 6. Biomass (dry weight) production by microalgae in fertilizer factory effluent exposed to crude petroleum hydrocarbon. ... microalgae profile included genera of cyanobacteria. (blue-green algae), Bacillariophycaea ...

  7. Lipid profiling of some authotrophic microalgae grown on waste water

    DEFF Research Database (Denmark)

    Safafar, Hamed; Jacobsen, Charlotte; Møller, Per

    Microalgae can be a new source of lipids for the aquaculture industry. Moreover, their potential as natural sources of antioxidants has gained recent attention. About 40 species of microalgae are used in aquaculture worldwide. A full characterization of lipid components is critical for selecting...

  8. Effect of photoacclimation on microalgae mass culture productivity

    NARCIS (Netherlands)

    Mooij, de Tim; Nejad, Zeynab Rajabali; Buren, van Lennard; Wijffels, René H.; Janssen, Marcel

    2017-01-01

    Microalgae are capable of adapting their pigmentation to the light regime to which they are exposed. In high density microalgae cultures exposed to sunlight, the high pigment content leads to oversaturation of the photosystems resulting in increased light energy dissipation at the reactor

  9. Techno-economical evaluation of protein extraction for microalgae biorefinery

    NARCIS (Netherlands)

    Sari, Y.W.; Sanders, J.P.M.; Bruins, M.

    2016-01-01

    Due to scarcity of fossil feedstocks, there is an increasing demand for biobased fuels. Microalgae are considered as promising biobased feedstocks. However, microalgae based fuels are not yet produced at large scale at present. Applying biorefinery, not only for oil, but also for other

  10. Assessment of microalgae-influenced biodeterioration of concrete ...

    African Journals Online (AJOL)

    The aim of this study was to isolate microalga involved in the biodeterioration of concrete structures. The growth of algae was monitored between day 1 and 18 using a spectrophotometer (Spectronic 721 model) at varying pH (4.2 and 9.4). To identify the microalgae, aliquots of the isolates was placed on microscope slides ...

  11. Chemical Profiles of Microalgae with Emphasis on Lipids: Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Benemann, J. R.; Tillett, D. M.; Suen, Y.; Hubbard, J.; Tornabene, T. G.

    1986-02-01

    This final report details progress during the third year of this subcontract. The overall objective of this subcontract was two fold: to provide the analytical capability required for selecting microalgae strains with high energy contents and to develop fundamental knowledge required for optimizing the energy yield from microalgae cultures. The progress made towards these objectives during this year is detailed in this report.

  12. Synergistic co-cultivation of activated sludge and microalgae in ...

    African Journals Online (AJOL)

    The influence of inoculation ratios of activated sludge and microalgae were investigated in this study in the aspects of biomass yield, lipid yield and total nitrogen (TN) removal efficiency. It was observed that mixed culture of activated sludge/microalgae with the ratio 1:1 and 1:0.75 achieved a maximum lipid production up to ...

  13. A mathematical model of microalgae growth in cylindrical photobioreactor

    Science.gov (United States)

    Bakeri, Noorhadila Mohd; Jamaian, Siti Suhana

    2017-08-01

    Microalgae are unicellular organisms, which exist individually or in chains or groups but can be utilized in many applications. Researchers have done various efforts in order to increase the growth rate of microalgae. Microalgae have a potential as an effective tool for wastewater treatment, besides as a replacement for natural fuel such as coal and biodiesel. The growth of microalgae can be estimated by using Geider model, which this model is based on photosynthesis irradiance curve (PI-curve) and focused on flat panel photobioreactor. Therefore, in this study a mathematical model for microalgae growth in cylindrical photobioreactor is proposed based on the Geider model. The light irradiance is the crucial part that affects the growth rate of microalgae. The absorbed photon flux will be determined by calculating the average light irradiance in a cylindrical system illuminated by unidirectional parallel flux and considering the cylinder as a collection of differential parallelepipeds. Results from this study showed that the specific growth rate of microalgae increases until the constant level is achieved. Therefore, the proposed mathematical model can be used to estimate the rate of microalgae growth in cylindrical photobioreactor.

  14. Novel approaches of producing bioenergies from microalgae: A recent review.

    Science.gov (United States)

    Tan, Chung Hong; Show, Pau Loke; Chang, Jo-Shu; Ling, Tau Chuan; Lan, John Chi-Wei

    2015-11-01

    Microalgae have caught the world's attention for its potential to solve one of the world's most pressing issues-sustainable green energy. Compared to biofuels supplied by oil palm, rapeseed, soybean and sugar cane, microalgae alone can be manipulated to generate larger amounts of biodiesel, bioethanol, biohydrogen and biomass in a shorter time. Apart from higher productivity, microalgae can also grow using brackish water on non-arable land, greatly reducing the competition with food and cash crops. Hence, numerous efforts have been put into the commercialisation of microalgae-derived biofuel by both the government and private bodies. This paper serves to review conventional and novel methods for microalgae culture and biomass harvest, as well as recent developments in techniques for microalgal biofuel production. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Effects of wastewater microalgae harvesting methods on polyhydroxybutyrate production.

    Science.gov (United States)

    Rahman, Asif; Anthony, Renil J; Sathish, Ashik; Sims, Ronald C; Miller, Charles D

    2014-03-01

    Microalgae have gained considerable attention recently as a sustainable means to produce biofuels and bioproducts. It has previously been demonstrated that single strain microalgae can be harvested and processed through a wet lipid extraction procedure (WLEP). After WLEP processing, acetone, butanol, ethanol, and biodiesel can be produced, and growth of recombinant Escherichia coli can be achieved from the microalgae. This study demonstrates the application of different wastewater microalgae harvesting techniques and processing through WLEP on the production of polyhydroxybutyrate (PHB) by E. coli. The harvesting techniques include: cationic potato starch (CPS), cationic corn starch (CCS), aluminum sulfate, and centrifugation. The microalgae-based media were used to grow E. coli to ∼10(13)CFU/mL and produce approximately 7.8% of dry cell weight as PHB. This study demonstrates the feasibility of harvesting wastewater algae to produce PHB and the potential for bioproduct generation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Peracetic acid is a suitable disinfectant for recirculating fish-microalgae integrated multi-trophic aquaculture systems

    DEFF Research Database (Denmark)

    Liu, Dibo; Behrens, Sascha; Pedersen, Lars-Flemming

    2016-01-01

    culture of a marine microalgae Tetraselmis chuii once per day for four days to four PAA productswith differing hydrogen peroxide (H2O2)/PAA proportions at two concentrations (1 and 2 mg L−1PAA).The H2O2solutions at equivalent total peroxide (H2O2+ PAA) concentrations were tested in parallel. Theresults...... show that the growth and photosynthesis of T. chuii were not affected by three of the PAA prod-ucts (Wofasteril®E400, Wofasteril®E250 and Applichem®150) and equivalent H2O2solutions at bothconcentrations. In contrast, Wofasteril®Lspez and an equivalent H2O2solution at both concentrationscaused...... irreversible culture collapse, photosynthesis dysfunction and irreversible cell damage. In con-clusion, PAA products with low proportions of H2O2are optimal disinfectants for fish-microalgae IMTAsystems....

  17. Culture of microalgae biomass for valorization of table olive processing water; Cultivo de biomasa de microalgas para la valorización del agua de elaboración de las aceitunas de mesa

    Energy Technology Data Exchange (ETDEWEB)

    Contreras, C.G.; Serrano, A.; Ruiz-Filippi, G.; Borja, R.; Fermoso, F.G.

    2016-07-01

    Table olive processing water (TOPW) contains many complex substances, such as phenols, which could be valorized as a substrate for microalgae biomass culture. The aim of this study was to assess the capability of Nannochloropsis gaditana to grow in TOPW at different concentrations (10- 80%) in order to valorize this processing water. Within this range, the highest increment of biomass was determined at percentage of 40% of TOPW, reaching an increment of 0.36 ± 0.05 mg volatile suspended solids (VSS)/L. Components of algal biomass were similar for the experiments at 10-40% of TOPW, where proteins were the major compounds (56-74%). Total phenols were retained in the microalgae biomass (0.020 ± 0.002 g of total phenols/g VSS). Experiments for 80% of TOPW resulted in a low production of microalgae biomass. High organic matter, nitrogen, phosphorus and phenol removal were achieved in all TOPW concentrations. Although high-value products, such as proteins, were obtained and high removal efficiencies of nutrients were determined, microalgae biomass culture should be enhanced to become a suitable integral processing water treatment. [Spanish] El agua resultante del proceso de elaboración de la aceituna de mesa (TOPW) presenta un elevado contenido en sustancias complejas, como fenoles, que podría permitir su uso como sustrato para el cultivo de microalgas. El objetivo de este estudio se centra en evaluar la capacidad de crecimiento de annochloropsis gaditana en TOPW a distintas concentraciones (10-80%) con vistas a la valorización de estas aguas. El mayor incremento de biomasa se obtuvo para un porcentaje del 40% de TOPW, alcanzando un aumento de 0.36 ± 0.50 mg sólidos en suspensión volátiles (SSV)/L. Los componentes presentes en la biomasa han sido similares para los experimentos con 10-40% de TOPW, siendo las proteínas los compuestos mayoritarios en todos los casos (56-74%). Los fenoles totales quedaron retenidos en las microalgas, alcanzando una concentraci

  18. Microalgae for Bioenergy; Key Technology Nodes

    Czech Academy of Sciences Publication Activity Database

    Maléterová, Ywetta; Kaštánek, František; Rousková, Milena; Matějková, Martina; Kaštánek, P.; Šolcová, Olga

    2015-01-01

    Roč. 2015, č. 2015 (2015), s. 597618 ISSN 1537-744X R&D Projects: GA MŠk LJ12002 Institutional support: RVO:67985858 Keywords : microalgae * oil production * water recycling Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 1.219, year: 2013 http://apps.webofknowledge.com/full_record.do?product=UA& search _mode=GeneralSearch&qid=14&SID=V2kH1WLyceq9ctvzW8I&page=1&doc=1

  19. Allelopathy as a potential strategy to improve microalgae cultivation

    Science.gov (United States)

    2013-01-01

    One of the main obstacles for continuous productivity in microalgae cultivation is the presence of biological contaminants capable of eliminating large numbers of cells in a matter of days or even hours. However, a number of strategies are being used to combat and prevent contamination in microalgae cultivation. These strategies include the use of extreme conditions in the culture media such as high salinity and high pH to create an unfavorable environment for the competitive organisms or predators of the microalgae. Numerous studies have explored the potential of naturally occurring bioactive secondary metabolites, which are natural products from plants and microorganisms, as a source of such compounds. Some of these compounds are herbicides, and marine and freshwater microalgae are a source of these compounds. Microalgae produce a remarkable diversity of biologically active metabolites. Results based on the allelopathic potential of algae have only been described for laboratory-scale production and not for algae cultivation on a pilot scale. The adoption of allelopathy on microalgal strains is an unexplored field and may be a novel solution to improve algae production. Here we present information showing the diversity of allelochemicals from microalgae and the use of an allelopathic approach to control microalgae cultivation on a pilot scale based on R&D activities being carried out in Brazil for biodiesel production. PMID:24499580

  20. Emergent Sources of Prebiotics: Seaweeds and Microalgae

    Directory of Open Access Journals (Sweden)

    Maria Filomena de Jesus Raposo

    2016-01-01

    Full Text Available In recent years, scientists have become aware that human microbiota, in general, and gut microbiota, in particular, play a major role in human health and diseases, such as obesity and diabetes, among others. A large number of evidence has come to light regarding the beneficial effects, either for the host or the gut microbiota, of some foods and food ingredients or biochemical compounds. Among these, the most promising seem to be polysaccharides (PS or their derivatives, and they include the dietary fibers. Some of these PS can be found in seaweeds and microalgae, some being soluble fibers, such as alginates, fucoidans, carrageenans and exopolysaccharides, that are not fermented, at least not completely, by colonic microbiota. This review gives an overview of the importance of the dietary fibers, as well as the benefits of prebiotics, to human health. The potential of the PS from marine macro- and microalgae to act as prebiotics is discussed, and the different techniques to obtain oligosaccharides from PS are presented. The mechanisms of the benefits of fiber, in general, and the types and benefits of algal fibers in human health are highlighted. The findings of some recent studies that present the potential effects of prebiotics on animal models of algal biomass and their extracts, as well as oligo- and polysaccharides, are presented. In the future, the possibility of using prebiotics to modulate the microbiome, and, consequently, prevent certain human diseases is foreseen.

  1. MICROALGAE AND CYANOBACTERIA: FOOD FOR THOUGHT(1).

    Science.gov (United States)

    Gantar, Miroslav; Svirčev, Zorica

    2008-04-01

    In non-Western civilizations, cyanobacteria have been part of the human diet for centuries. Today, microalgae and cyanobacteria are either produced in controlled cultivation processes or harvested from the natural habitats and marketed as food supplements around the world. Cyanobacteria produce a vast array of different biologically active compounds, some of which are expected to be used in drug development. The fact that some of the active components from cyanobacteria potentially have anticancer, antimicrobial, antiviral, anti-inflammatory, and other effects is being used for marketing purposes. However, introduction of these products in the form of whole biomass for alimentary purposes raises concerns regarding the potential toxicity and long-term effects on human health. Here, we review data on the use of cyanobacteria and microalgae in human nutrition and searched for available information on legislature that regulates the use of these products. We have found that, although the quality control of these products is most often self-regulated by the manufacturers, different governmental agencies are introducing strict regulations for placing novel products, such as algae and cyanobacteria, on the market. The existing regulations require these products to be tested for the presence of toxins, such as microcystin; however, other, sometimes novel, toxins remain undetected, and their long-term effects on human health remain unknown. © 2008 Phycological Society of America.

  2. Emergent Sources of Prebiotics: Seaweeds and Microalgae

    Science.gov (United States)

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

    2016-01-01

    In recent years, scientists have become aware that human microbiota, in general, and gut microbiota, in particular, play a major role in human health and diseases, such as obesity and diabetes, among others. A large number of evidence has come to light regarding the beneficial effects, either for the host or the gut microbiota, of some foods and food ingredients or biochemical compounds. Among these, the most promising seem to be polysaccharides (PS) or their derivatives, and they include the dietary fibers. Some of these PS can be found in seaweeds and microalgae, some being soluble fibers, such as alginates, fucoidans, carrageenans and exopolysaccharides, that are not fermented, at least not completely, by colonic microbiota. This review gives an overview of the importance of the dietary fibers, as well as the benefits of prebiotics, to human health. The potential of the PS from marine macro- and microalgae to act as prebiotics is discussed, and the different techniques to obtain oligosaccharides from PS are presented. The mechanisms of the benefits of fiber, in general, and the types and benefits of algal fibers in human health are highlighted. The findings of some recent studies that present the potential effects of prebiotics on animal models of algal biomass and their extracts, as well as oligo- and polysaccharides, are presented. In the future, the possibility of using prebiotics to modulate the microbiome, and, consequently, prevent certain human diseases is foreseen. PMID:26828501

  3. Emergent Sources of Prebiotics: Seaweeds and Microalgae.

    Science.gov (United States)

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

    2016-01-28

    In recent years, scientists have become aware that human microbiota, in general, and gut microbiota, in particular, play a major role in human health and diseases, such as obesity and diabetes, among others. A large number of evidence has come to light regarding the beneficial effects, either for the host or the gut microbiota, of some foods and food ingredients or biochemical compounds. Among these, the most promising seem to be polysaccharides (PS) or their derivatives, and they include the dietary fibers. Some of these PS can be found in seaweeds and microalgae, some being soluble fibers, such as alginates, fucoidans, carrageenans and exopolysaccharides, that are not fermented, at least not completely, by colonic microbiota. This review gives an overview of the importance of the dietary fibers, as well as the benefits of prebiotics, to human health. The potential of the PS from marine macro- and microalgae to act as prebiotics is discussed, and the different techniques to obtain oligosaccharides from PS are presented. The mechanisms of the benefits of fiber, in general, and the types and benefits of algal fibers in human health are highlighted. The findings of some recent studies that present the potential effects of prebiotics on animal models of algal biomass and their extracts, as well as oligo- and polysaccharides, are presented. In the future, the possibility of using prebiotics to modulate the microbiome, and, consequently, prevent certain human diseases is foreseen.

  4. 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 towards becoming economically feasible. Thus, it is essential that future research is directed towards improving these processes. This article is protected by copyright. All rights reserved. © 2018 American Institute of Chemical Engineers.

  5. Desempenho de cordeiros confinados, alimentados com dietas à base de torta de girassol

    Directory of Open Access Journals (Sweden)

    Deivison Novaes Rodrigues

    2013-04-01

    Full Text Available O objetivo deste trabalho foi avaliar os efeitos da inclusão da torta de girassol na dieta de cordeiros em confinamento sobre o desempenho produtivo dos animais. Utilizaram-se 40 cordeiros sem raça definida, não castrados, com peso médio inicial de 20,17±2,66 kg, alimentados com 0, 7, 14, 21 e 28% de torta de girassol na dieta (base seca. O experimento foi conduzido em delineamento de blocos ao acaso. A inclusão de torta de girassol na dieta não alterou o consumo médio de matéria seca (883,58 g por dia, a conversão alimentar (4,40 e o consumo médio de água (2,59 L por dia. O aumento dos níveis de torta de girassol diminuiu linearmente o peso final, o ganho de peso total, o ganho de peso diário e a área de olho de lombo. O nível de inclusão de até 28% não afeta o consumo médio de matéria seca e de água, mas reduz o desempenho e a área de olho de lombo. Para obter o menor custo com a dieta, o nível de inclusão da torta de girassol pode atingir até 28% da matéria seca, quando o seu preço representar até 40% do preço da mistura entre milho e farelo de soja.

  6. Consumo e desempenho produtivo de ovinos alimentados com dietas que continham coprodutos do desfibramento do sisal

    Directory of Open Access Journals (Sweden)

    R.D. Santos

    2011-12-01

    Full Text Available Avaliaram-se o desempenho produtivo e o consumo de nutrientes e frações fibrosas em ovinos alimentados com dietas contendo coprodutos do desfibramento do sisal, Agave sisalana. Foram utilizados 24 ovinos, machos, alojados em baias individuais. O delineamento experimental utilizado foi o inteiramente ao acaso, com quatro tratamentos e seis repetições. Os tratamentos consistiram em quatro dietas isoproteicas, em que: i dieta padrão, contendo 38% de volumoso (silagem de milheto e 62% de concentrado (milho, farelo de soja e ureia; ii inclusão de 20% da silagem de mucilagem do sisal em substituição à silagem de milheto; iii inclusão de 20% da silagem de mucilagem associada ao pó da batedeira como aditivo em substituição à silagem de milheto; iv inclusão de 20% do feno da mucilagem em substituição à silagem de milheto. O peso corporal final, os ganhos médio diário e total e a conversão alimentar dos ovinos não foram influenciados pelas dietas avaliadas (P>0,05. Os consumos dos nutrientes, em g/dia e em %PC e g/kg0,75, não sofreram influência das dietas. Os resultados indicam que as dietas à base de coprodutos do sisal podem ser utilizadas como alternativa volumosa, além de possibilitar o aumento da rentabilidade da atividade na região semiárida brasileira.

  7. Cultivo de microalgas Isochrysis galbana y Nannochloropsis sp. para alimentación de larvas de peces marinos

    Directory of Open Access Journals (Sweden)

    María Fernanda Pereira Gutiérrez

    2017-09-01

    Full Text Available En la producción de alimento vivo, representado principalmente por microalgas, se buscan nuevas técnicas de medios de cultivo sustituyendo las fórmulas tradicionales en aras de reducir costos. Teniendo en cuenta esto, se usó un medio no convencional (fertilizantes industriales para producir las microalgas Isochrysis galbana y Nannochloropsis sp. en cultivos estáticos, y se alcanzaron densidades de 7,5 × 106 cel mL–1 de Nannochloropsis sp. en 1000 L y 0,265 × 106 cel mL–1 de I. galbana en 250 L. Hubo un crecimiento exponencial, que se alcanzó entre los tres y los ocho días, en que se duplicaron las densidades iniciales. Se sugiere cosechar en lapsos cortos (hasta cuatro días, debido a la proliferación de contaminantes y la disminución de la calidad de las células con el tiempo. Se concluye que el medio diseñado para el enriquecimiento del cultivo es una alternativa viable para la producción de las microalgas que permite satisfacer la demanda alimenticia en el levante de larvas de peces marinos.

  8. Experimentacion y Optimizacion Conjunta de la Disrupcion Celular de Microalgas y Extraccion Soxhletde Aceite Para Alimentacion y Biocombustibles

    Directory of Open Access Journals (Sweden)

    Angel D González Delgado

    2014-03-01

    Full Text Available La producción de biocombustibles y bioproductos utilizando microalgas puede realizarse con tratamientos térmicos para producir biocrudo, o mediante la extracción y transformación de metabolitos específicos. Esta última alternativa incluye las etapas de cultivo, cosecha, secado, extracción de lípidos y purificación o transformación de los mismos. La factibilidad técnica y económica de la obtención de bioproductos derivados del aceite de microalgas depende en gran medida de la eficiencia de extracción de los lípidos. El objetivo principal de este trabajo es establecer una metodología para la disrupción celular y extracción soxhlet de aceite de microalgas, y determinar su efectividad en tres cepas nativas; Amphiprora, Desmodesmus y Tetraselmis. Se evaluó el efecto de distintos métodos de disrupción celular como MSA, MHA, HA4M Fast, y HA0.5M Slow,solventes como hexano, ciclohexano y metanol, y tiempos de extracción de 4,6 y 8 horas, sobre la cantidad de aceite extraído. La mayor eficiencia de extracción se obtuvo utilizando disrupción celular MSA. El mejor solvente fue hexano y el mejor tiempo de extracción fue de 8 horas.

  9. Anaerobic biodegradation of lipids of the marine microalga Nannochloropsis salina

    NARCIS (Netherlands)

    Sinninghe Damsté, J.S.; Grossi, V.; Blokker, P.

    2001-01-01

    In order to determine the susceptibility to anaerobic biodegradation of the different lipid biomarkers present in a marine microalga containing algaenan, portions of one large batch of cultured Nannochloropsis salina (Eustigmatophyceae) were incubated in anoxic sediment slurries for various times.

  10. Potential biotechnological application of microalgae: a critical review.

    Science.gov (United States)

    Odjadjare, Ejovwokoghene C; Mutanda, Taurai; Olaniran, Ademola O

    2017-02-01

    Microalgae are diverse microorganisms inhabiting a wide range of habitats with only a small fraction being cultivated for human use. Recently, interest in microalgal research has increased in the quest for alternative renewable fuels due to possible depletion of fossil fuels in the near future. However, costly downstream processing has hampered the commercialization of biofuels derived from microalgae. Several value added products of industrial, pharmaceutical and agricultural relevance could be simultaneously derived from microalgae during bioenergy production. Despite these value-added products having the potential to offset the high cost of downstream processing of renewable fuels, their production has not been explored in-depth. This review presents a critical overview of the current state of biotechnological applications of microalgae for human benefit and highlights possible areas for further research and development.

  11. Microalgae as healthy ingredients for functional food: a review.

    Science.gov (United States)

    Matos, J; Cardoso, C; Bandarra, N M; Afonso, C

    2017-08-01

    Microalgae are very interesting and valuable natural sources of highly valuable bioactive compounds, such as vitamins, essential amino acids, polyunsaturated fatty acids, minerals, carotenoids, enzymes and fibre. Due to their potential, microalgae have become some of the most promising and innovative sources of new food and functional products. Moreover, microalgae can be used as functional ingredients to enhance the nutritional value of foods and, thus, to favourably affect human health by improving the well-being and quality of life, but also by curtailing disease and illness risks. This review provides an overview of the current knowledge of the health benefits associated with the consumption of microalgae, bioactive compounds, functional ingredients, and health foods.

  12. 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

  13. Pretreatment of microalgae to improve biogas production: a review.

    Science.gov (United States)

    Passos, Fabiana; Uggetti, Enrica; Carrère, Hélène; Ferrer, Ivet

    2014-11-01

    Microalgae have been intensively studied as a source of biomass for replacing conventional fossil fuels in the last decade. The optimization of biomass production, harvesting and downstream processing is necessary for enabling its full-scale application. Regarding biofuels, biogas production is limited by the characteristics of microalgae, in particular the complex cell wall structure of most algae species. Therefore, pretreatment methods have been investigated for microalgae cell wall disruption and biomass solubilization before undergoing anaerobic digestion. This paper summarises the state of the art of different pretreatment techniques used for improving microalgae anaerobic biodegradability. Pretreatments were divided into 4 categories: (i) thermal; (ii) mechanical; (iii) chemical and (iv) biological methods. According to experimental results, all of them are effective at increasing biomass solubilization and methane yield, pretreatment effect being species dependent. Pilot-scale research is still missing and would help evaluating the feasibility of full-scale implementation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Hydrodynamic study of an internal airlift reactor for microalgae culture.

    Science.gov (United States)

    Rengel, Ana; Zoughaib, Assaad; Dron, Dominique; Clodic, Denis

    2012-01-01

    Internal airlift reactors are closed systems considered today for microalgae cultivation. Several works have studied their hydrodynamics but based on important solid concentrations, not with biomass concentrations usually found in microalgae cultures. In this study, an internal airlift reactor has been built and tested in order to clarify the hydrodynamics of this system, based on microalgae typical concentrations. A model is proposed taking into account the variation of air bubble velocity according to volumetric air flow rate injected into the system. A relationship between riser and downcomer gas holdups is established, which varied slightly with solids concentrations. The repartition of solids along the reactor resulted to be homogenous for the range of concentrations and volumetric air flow rate studied here. Liquid velocities increase with volumetric air flow rate, and they vary slightly when solids are added to the system. Finally, liquid circulation time found in each section of the reactor is in concordance with those employed in microalgae culture.

  15. Phototrophic pigment production with microalgae: biological constraints and opportunities

    NARCIS (Netherlands)

    Mulders, K.J.M.; Lamers, P.P.; Martens, D.E.; Wijffels, R.H.

    2014-01-01

    There is increasing interest in naturally produced colorants, and microalgae represent a bio-technologically interesting source due to their wide range of colored pigments, including chlorophylls (green), carotenoids (red, orange and yellow), and phycobiliproteins (red and blue). However, the

  16. 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

  17. Bioflocculation: An alternative strategy for harvesting of microalgae - An overview.

    Science.gov (United States)

    Ummalyma, Sabeela Beevi; Gnansounou, Edgard; Sukumaran, Rajeev K; Sindhu, Raveendran; Pandey, Ashok; Sahoo, Dinabandhu

    2017-10-01

    Microalgae based research has been extensively progressed for the production of value added products and biofuels. Potential application of microalgae for biofuel is recently gained more attention for possibilities of biodiesel and other high value metabolites. However, high cost of production of biomass associated with harvesting technologies is one of the major bottleneck for commercialization of algae based industrial product. Based on the operation economics, harvesting efficiency, technological possibilities, flocculation of algal biomass is a superior method for harvesting microalgae from the growth medium. In this article, latest trends of microalgal cell harvesting through flocculation are reviewed with emphasis on current progress and prospect in environmental friendly bio-based flocculation approach. Bio-flocculation based microalgae harvesting technologies is a promising strategy for low cost microalgal biomass production for various applications. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Microalgae, a Potential Natural Functional Food Source – a Review

    Directory of Open Access Journals (Sweden)

    Villarruel-López Angélica

    2017-12-01

    Full Text Available Microalgae are a group of microorganisms used in aquaculture. The number of studies regarding their use as a functional food has recently increased due to their nutritional and bioactive compounds such as polysaccharides, fatty acids, bioactive peptides, and pigments. Specific microalgal glucans (polysaccharides can activate the immune system or exert antioxidant and hypocholesterolemic effects. The importance of algal lipids is based on their polyunsaturated fatty acids, their anti-inflammatory effects, their modulation of lipid pathways, and their neuroprotective action. Microalgae peptides can bind or inhibit specific receptors in cardiovascular diseases and cancer, while carotenoids can act as potent antioxidants. The beneficial biological activity will depend on the specific microalga and its chemical constituents. Therefore, knowledge of the composition of microalgae would aid in identifying, selecting, and studying their functional effects.

  19. IMPLEMENTACIÓN DE UN SISTEMA DE ALIMENTACIÓN ININTERRUMPIDA, CON VISUALIZACIÓN DE PARÁMETROS ELÉCTRICOS EN LCD

    Directory of Open Access Journals (Sweden)

    Franklin Giovanni Parra

    2013-07-01

    Full Text Available Este artículo presenta el diseño y la implementación de un sistema de alimentación ininterrumpida (UPS con visualización de parámetros eléctricos (tensión, corriente y potencia en una pantalla de cristal líquido (LCD, realizado mediante procesos lógico-matemáticos programados en un microcontrolador, con el fin de brindar alimentación constante a una carga crítica y a su vez conocer el comportamiento de las variables eléctricas del dispositivo que requiera ser alimentado.

  20. Microalgae-microbial fuel cell: A mini review.

    Science.gov (United States)

    Lee, Duu-Jong; Chang, Jo-Shu; Lai, Juin-Yih

    2015-12-01

    Microalgae-microbial fuel cells (mMFCs) are a device that can convert solar energy to electrical energy via biological pathways. This mini-review lists new research and development works on microalgae processes, microbial fuel cell (MFC) processes, and their combined version, mMFC. The substantial improvement and technological advancement are highlighted, with a discussion on the challenges and prospects for possible commercialization of mMFC technologies. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. POSSIBILITIES OF CARBON DIOXIDE FIXATION BY MICROALGAE IN REFINERY

    OpenAIRE

    Šingliar, Michal; Mikulec, Jozef; Kušnir, Patrik; Polakovičova, Gabriela

    2013-01-01

    Capture and sequestration of carbon dioxide is one of the most critical challenges today for businesses and governments worldwide. Thousands of emitting power plants and industries worldwide face this costly challenge – reduce the CO2 emissions or pay penalties. One possibility for carbon dioxide sequestration is its fixation in microalgae. Microalgae can sequester CO2 from flue gases emitted from fossil fuel-fired refinery plants and units, thereby reducing emissions of a major greenhouse ga...

  2. Harvesting of freshwater microalgae biomass by Scenedesmus sp. as bioflocculant

    Science.gov (United States)

    Rinanti, A.; Purwadi, R.

    2018-01-01

    This study is particularly expected to provide information on the diversity of microalgae as the flocculant agent that gives the highest biomass yield. Bioflocculation was done by using one of the flocculating microalgae i.e. Scenedesmus obliquus to concentrate on non-flocculating microalgae Chlorella vulgaris. The freshwater microalgae S. obliquus tested it ability to harvest other non-flocculating microalgae, increased sedimentation rate in the flocculation process and increased biomass yield. The flocculation of biomass microalgae with chemical flocculant as comparison was done by adding alum (K2SO4·Al2 (SO4)3·24H2O). The addition of alum (K2SO4·Al2 (SO4)3·24H2O) as flocculant at pH 11 and S. obliquus sp. as bioflocculant caused significant alteration of nutrition of microalgae. Overall, the essential content produced by flocculation method with addition of alum or with bioflocculation (%, mg/100 mg dry weight) are lipid 31,64; 38,69, protein 30,79; 38.50%, and chlorophyll 0.6253; 0.8420). Harvesting with bioflocculation methods conducted at the end of the cultivation period increase the amount of biomass significantly and can accelerate the settling time of biomass. Harvesting microalgae cells by bioflocculation method becomes an economically competitive harvesting method compared to alum as a chemical flocculant because of the cheaper cost of flocculant, not toxic so it does not require further water treatment after harvesting due to the use of alum as chemical flocculants.

  3. Biogas from Co-digestion of Sewage Sludge and Microalgae

    OpenAIRE

    Thorin, Eva; Olsson, Jesper; Schwede, Sebastian; Nehrenheim, Emma

    2017-01-01

    Microalgae cultivated in waste water could contribute to increased biomass production at municipal waste watertreatment plants. The biomass could be utilized for biogas production when co-digested with sewage sludge. In thispaper previous published results on co-digestion of sewage sludge and microalgae are summarized and remainingknowledge gaps are identified. The available batch tests in literature mostly concern digestion at mesophilicconditions. Some of those tests indicate a synergetic e...

  4. Biodiesel de microalgas: avanços e desafios

    Directory of Open Access Journals (Sweden)

    André Luiz Custódio Franco

    2013-01-01

    Full Text Available Microalgae biomass has been described by several authors as the raw material with the greatest potential to meet the goals of replacing petroleum diesel by biodiesel while not competing with arable land suitable for food production. Research groups in different countries are seeking the most appropriate production model for productivity, economic viability and environmental sustainability. This review focused on recent advances and challenges of technology for the production of biodiesel from microalgae, including the procedures used to obtain biomass.

  5. Microalgae as Sustainable Renewable Energy Feedstock for Biofuel Production

    Directory of Open Access Journals (Sweden)

    Srikanth Reddy Medipally

    2015-01-01

    Full Text Available The world energy crisis and increased greenhouse gas emissions have driven the search for alternative and environmentally friendly renewable energy sources. According to life cycle analysis, microalgae biofuel is identified as one of the major renewable energy sources for sustainable development, with potential to replace the fossil-based fuels. Microalgae biofuel was devoid of the major drawbacks associated with oil crops and lignocelluloses-based biofuels. Algae-based biofuels are technically and economically viable and cost competitive, require no additional lands, require minimal water use, and mitigate atmospheric CO2. However, commercial production of microalgae biodiesel is still not feasible due to the low biomass concentration and costly downstream processes. The viability of microalgae biodiesel production can be achieved by designing advanced photobioreactors, developing low cost technologies for biomass harvesting, drying, and oil extraction. Commercial production can also be accomplished by improving the genetic engineering strategies to control environmental stress conditions and by engineering metabolic pathways for high lipid production. In addition, new emerging technologies such as algal-bacterial interactions for enhancement of microalgae growth and lipid production are also explored. This review focuses mainly on the problems encountered in the commercial production of microalgae biofuels and the possible techniques to overcome these difficulties.

  6. Microalgae - A promising tool for heavy metal remediation.

    Science.gov (United States)

    Suresh Kumar, K; Dahms, Hans-Uwe; Won, Eun-Ji; Lee, Jae-Seong; Shin, Kyung-Hoon

    2015-03-01

    Biotechnology of microalgae has gained popularity due to the growing need for novel environmental technologies and the development of innovative mass-production. Inexpensive growth requirements (solar light and CO2), and, the advantage of being utilized simultaneously for multiple technologies (e.g. carbon mitigation, biofuel production, and bioremediation) make microalgae suitable candidates for several ecofriendly technologies. Microalgae have developed an extensive spectrum of mechanisms (extracellular and intracellular) to cope with heavy metal toxicity. Their wide-spread occurrence along with their ability to grow and concentrate heavy metals, ascertains their suitability in practical applications of waste-water bioremediation. Heavy metal uptake by microalgae is affirmed to be superior to the prevalent physicochemical processes employed in the removal of toxic heavy metals. In order to evaluate their potential and to fill in the loopholes, it is essential to carry out a critical assessment of the existing microalgal technologies, and realize the need for development of commercially viable technologies involving strategic multidisciplinary approaches. This review summarizes several areas of heavy metal remediation from a microalgal perspective and provides an overview of various practical avenues of this technology. It particularly details heavy metals and microalgae which have been extensively studied, and provides a schematic representation of the mechanisms of heavy metal remediation in microalgae. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. Microalgae as sustainable renewable energy feedstock for biofuel production.

    Science.gov (United States)

    Medipally, Srikanth Reddy; Yusoff, Fatimah Md; Banerjee, Sanjoy; Shariff, M

    2015-01-01

    The world energy crisis and increased greenhouse gas emissions have driven the search for alternative and environmentally friendly renewable energy sources. According to life cycle analysis, microalgae biofuel is identified as one of the major renewable energy sources for sustainable development, with potential to replace the fossil-based fuels. Microalgae biofuel was devoid of the major drawbacks associated with oil crops and lignocelluloses-based biofuels. Algae-based biofuels are technically and economically viable and cost competitive, require no additional lands, require minimal water use, and mitigate atmospheric CO2. However, commercial production of microalgae biodiesel is still not feasible due to the low biomass concentration and costly downstream processes. The viability of microalgae biodiesel production can be achieved by designing advanced photobioreactors, developing low cost technologies for biomass harvesting, drying, and oil extraction. Commercial production can also be accomplished by improving the genetic engineering strategies to control environmental stress conditions and by engineering metabolic pathways for high lipid production. In addition, new emerging technologies such as algal-bacterial interactions for enhancement of microalgae growth and lipid production are also explored. This review focuses mainly on the problems encountered in the commercial production of microalgae biofuels and the possible techniques to overcome these difficulties.

  8. 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.

  9. Microalgae as Sustainable Renewable Energy Feedstock for Biofuel Production

    Science.gov (United States)

    Yusoff, Fatimah Md.; Shariff, M.

    2015-01-01

    The world energy crisis and increased greenhouse gas emissions have driven the search for alternative and environmentally friendly renewable energy sources. According to life cycle analysis, microalgae biofuel is identified as one of the major renewable energy sources for sustainable development, with potential to replace the fossil-based fuels. Microalgae biofuel was devoid of the major drawbacks associated with oil crops and lignocelluloses-based biofuels. Algae-based biofuels are technically and economically viable and cost competitive, require no additional lands, require minimal water use, and mitigate atmospheric CO2. However, commercial production of microalgae biodiesel is still not feasible due to the low biomass concentration and costly downstream processes. The viability of microalgae biodiesel production can be achieved by designing advanced photobioreactors, developing low cost technologies for biomass harvesting, drying, and oil extraction. Commercial production can also be accomplished by improving the genetic engineering strategies to control environmental stress conditions and by engineering metabolic pathways for high lipid production. In addition, new emerging technologies such as algal-bacterial interactions for enhancement of microalgae growth and lipid production are also explored. This review focuses mainly on the problems encountered in the commercial production of microalgae biofuels and the possible techniques to overcome these difficulties. PMID:25874216

  10. Review Paper on Cell Membrane Electroporation of Microalgae using Electric Field Treatment Method for Microalgae Lipid Extraction

    Science.gov (United States)

    Joannes, C.; Sipaut, C. S.; Dayou, J.; Yasir, S. M.; Mansa, R. F.

    2015-04-01

    The paper reviews the recent studies on the lipid extraction of microalgae that mainly highlighted on the cell disruption method using variety of microalgae species. Selection of cell disruption method and devices are crucial in order to achieve the highest extraction percentage of lipid and other valuable intracellular (proteins, carotenoids and chlorophylls) from microalgae cell. Pulsed electric field (PEF) and electrochemical lysis methods were found to be potential for enhancing the extraction efficiencies either conducted in single step extraction or used as pre-treatment followed by conventional extraction method. The PEF technology capable to extract lipid as high as 75%. While, electrochemical lysis treatment capable to extract lipid approximately 93% using Stainless Steel (SS) and Ti/IrO2 as the cathode and anode electrode respectively. PEF technology and electrochemical lysis are still considered to be a new method for microalgae lipid extraction and further investigation can still be done for better improvement of the system.

  11. Variation in lipid extractability by solvent in microalgae. Additional criterion for selecting species and strains for biofuel production from microalgae.

    Science.gov (United States)

    Mendoza, Héctor; Carmona, Laura; Assunção, Patricia; Freijanes, Karen; de la Jara, Adelina; Portillo, Eduardo; Torres, Alicia

    2015-12-01

    The lipid extractability of 14 microalgae species and strains was assessed using organic solvents (methanol and chloroform). The high variability detected indicated the potential for applying this parameter as an additional criterion for microalgae screening in industrial processes such as biofuel production from microalgae. Species without cell walls presented higher extractability than species with cell walls. Analysis of cell integrity by flow cytometry and staining with propidium iodide showed a significant correlation between higher resistance to the physical treatments of cell rupture by sonication and the lipid extractability of the microalgae. The results highlight the cell wall as a determining factor in the inter- and intraspecific variability in lipid extraction treatments. Copyright © 2015. Published by Elsevier Ltd.

  12. Suplementaci??n de la dieta de ovejas lecheras con aceite de girasol y l??pidos marinos para modificar la composici??n de la grasa de la leche: efecto sobre el rendimiento productivo de los animales, la microbiota y las caracter??sticas de la fermentaci??n ruminal y el perfil de ??cidos grasos de la leche y la digesta

    OpenAIRE

    Guti??rrez Toral, Pablo

    2011-01-01

    214 p. Se han realizado cinco experimentos con ovejas, con el objetivo de investigar el efecto de la suplementaci??n con aceite de girasol y, o bien aceite de pescado, o bien microalgas marinas, sobre la composici??n de los ??cidos grasos de la leche y la digesta, la micriobiota, la fermantaci??n ruminal y el rendimiento productivo de los animales

  13. Cultivation of microalgae in industrial wastewaters

    DEFF Research Database (Denmark)

    van Wagenen, Jonathan Myerson

    Microalgae production for the purpose of clearing wastewater has been researched for at least half a century. Such systems have a dual benefit: first, they prevent nutrients from entering water bodies and causing eutrophication; second, they transform sunlight and carbon dioxide into a biomass...... cultivation. When algae are grown within a wastewater treatment plant, the use of the chemical energy stored in the organic carbon dissolved in the wastewater could also be a useful option. Conventional aerobic sewage treatment expends much energy in breaking down the biomass to CO2. However, various...... of the nutritionally important α-Linoleic fatty acid increased when light intensity and dilution rate were higher. Valuable pigments lutein, carotene and other carotenoids were higher in low-light conditions. The results from this thesis demonstrate that industrial wastewater can be a suitable replacement for algae...

  14. Desempenho de bezerros alimentados usando de sucedâneo até 56 dias de idade

    Directory of Open Access Journals (Sweden)

    Silvia Resende de Albuquerque França

    2011-12-01

    Full Text Available Trinta bezerros machos da raça Holandesa foram alojados em piquetes a partir do quinto dia de vida, distribuídos em dois grupos. Todos os animais foram alimentados com concentrado comercial peletizado, tendo o primeiro grupo recebido leite integral (grupo-controle e o outro, sucedâneo formulado com proteínas de soja, de soro de leite e de leite desnatado em pó (grupo tratamento, num único horário de fornecimento, até 56 dias de vida. Os animais tinham acesso ad libitum à água e ao sal mineral. Suas medidas de peso vivo e altura de ísquio foram tomadas semanalmente. O desenvolvimento em estatura não diferiu entre os tratamentos, e o ganho em peso foi inferior para os animais alimentados com sucedâneo. O menor ganho em peso foi influenciado pelo menor consumo de concentrado e de matéria seca da dieta.

  15. Lipid extraction of wet BLT0404 microalgae for biofuel application

    Science.gov (United States)

    Mansur, Dieni; Fitriady, Muhammad Arifuddin; Susilaningsih, Dwi; Simanungkalit, Sabar Pangihutan; Agustian, Egi

    2017-01-01

    Recently, research and development of microalgae for biodiesel production were conducted by researchers in the world. This research becomes popular because of an exponential growth of the microalgae under nutrient limitation. Lipid of microalgae grows faster than oil producing land crops. Therefore, microalgae lipid content could improve the economics of biodiesel production. The aim of this study was to investigate yield of lipid extract and chemicals compounds containing in non-acylglycerol neutral lipid from BLT 0404 microalga. The study was conducted because lipid extraction was an important step for biodiesel as well as biofuel production. The extraction was carried out using polar and non-polar mixture solvents. The polar solvent was methanol and non-polar one was chloroform. Process extraction was conducted under various stirring time between the microalgae and methanol and volume ratio between the methanol and chloroform. Methanol as a polar solvent was able to extract polar lipid (phospholipid and glycolipid) because it removed polar membrane lipid and lipid-associated to polar molecule. Moreover, the non-polar solvent was used for extraction non-acylglycerol neutral lipid (hydrocarbons, sterols, ketones, free fatty acids, carotenes, and chlorophylls) for biofuel production. Under ratio of microalgae: methanol: chloroform of 0.8: 4: 2 that stirring time of the microalgae with methanol was 30 min yielded 58% of total lipid extract. The yield value consisted of 14.5% of non-acylglycerol neutral lipid and 43.5% of polar lipid. The non-acylglycerol neutral lipid will be converted into biofuel. Therefore, analysis of its chemical compounds was required. The non-acylglycerol neutral lipid was analyzed by GCMS and found that the extract contained long chains of hydrocarbon compounds. The hydrocarbons consisted of C18-C30 that high peaks with larger percentage area were C20-C26. The results suggested that stirring between microalgae and methanol for 30 min was

  16. Short-term antioxidative responses of 15 microalgae exposed to excessive irradiance including ultraviolet radiation

    NARCIS (Netherlands)

    Janknegt, Paul J.; De Graaff, C. Marco; Van De Poll, Willem H.; Visser, Ronald J. W.; Rijstenbil, Jan W.; Buma, Anita G. J.

    2009-01-01

    Short-term photosensitivity and oxidative stress responses were compared for three groups of marine microalgae: Antarctic microalgae, temperate diatoms and temperate flagellates. In total, 15 low-light-acclimated species were exposed to simulated surface irradiance including ultraviolet radiation

  17. Estudo comparativo do ciclo evolutivo de Rhodnius neglectus alimentados em pombos ou camundongos

    Directory of Open Access Journals (Sweden)

    Liléia Diotaiuti

    1987-06-01

    Full Text Available Baseados no encontro de 77,2% de reação de precipitina positiva para soro antiave de R. neglectus capturados em palmeiras da periferia de Belo Horizonte, estudamos o ciclo evolutivo de uma colonia recém-estabelecida no laboratório alimentada com sangue de pombo ou camundongo, na expectativa de demonstrarmos maior adaptação deste triatomíneo ao sangue da ave. Para comparação, estudamos o ciclo evolutivo destes insetos numa colônia há muito mantida em insetário. Nossos resultados mostram um desenvolvimento mais rápido da colônia recém- estabelecida, assim como do lote de triatomíneos alimentado em camundongo. Esses achados sugerem menor potencial biológico para triatomíneos criados por longo tempo em insetário em comparação a novas colônias. Sendo as aves os principais habitantes das palmeiras, a aparente preferência alimentar por sangue de aves demonstrada pela reação de precipitina parece ser circunstancial e não seletiva na busca do sangue com o qual o triatomíneo obteria melhor desenvolvimento.Feeding pattems of R. neglectus collected in palm trees around Belo Horizonte (Minas Gerais, Brazil were investigated. Precipitin tests showed 77.2% of avian blood. In view of these results, a new colony of R. neglectus established in the laboratory was fed regularly on pigeons or mice, in order to verify a possible better adaptation of this insect to the avian blood. As a control group a colony of R neglectus which has been maintained for several years in the laboratory was also observed. The results show a better development of the “new" colony in comparison with the old one, and of those bugs nourished with mice blood. Such findings suggest a poorer biological potential for triatomines maintained for long time in artificial conditions, in comparison with those living in the natural environment. As birds are the main vertebrate inhabitants of palm trees (the natural ecotope of R neglectus, the apparent feeding preference of

  18. Cationic Starch Synthesis, Development, and Evaluation for Harvesting Microalgae for Wastewater Treatment

    OpenAIRE

    Anthony, Renil John

    2013-01-01

    In the quest for a feedstock for the production of biofuels, microalgae are showing potential. High photosynthetic efficiency, combined with high lipid content and low fresh water requirement, has contributed to the 'biofuels feedstock' status of microalgae. In some communities, microalgae have also been cultivated in wastewater in facultative lagoons to remove phosphorus and nitrogen through the growth of microalgae. With such systems in place, complete biological wastewater treatment can be...

  19. Cultivo de las microalgas dulceacuícolas Kirchneriella obesa, Scenedesmus quadricauda y Chlorococcum infusorium empleando tres medios de cultivo

    Directory of Open Access Journals (Sweden)

    A. A. Ortega-Salas

    2012-01-01

    Full Text Available Se cultivaron las microalgas dulceacuícolas Kirchneriella obesa (G. S. West Schmidle 1893, Scenedesmus quadricauda (Chodat, Turpin Bréb 1835 y Chlorococcum infusorium (Schrank Meneghini 1842, con el propósito comparar las tasas de crecimiento y su rendimiento en tres medios de cultivo, el F/2 de Guillard, Fert I y Fert II. El agua utilizada se pasó en filtros de cinco, uno y 0.45 mm, y se trató con luz ultravioleta. La temperatura varió de 24 a 25°C. Se cultivaron en un sistema de volumen creciente a partir de recipientes de 62.5 mL, duplicando el medio de cultivo cada 24 h, con el fin de completar 32 L en nueve días. Cada 24 h se obtuvieron tres muestras de 1 a 10 mL del cultivo, se preservaron en una solución de lugol y se calculó la concentración de las microalgas cada 24 h. El número total de células de las tres especies aumentó de manera exponencial hasta el final de los experimentos en los medios de cultivo F/2 y Fert I; esto no fue así con el medio Fert II, en el cual la tasa de duplicación y el número total de divisiones fueron más bajas. El medio F/2 y el Fert I ofrecieron mejores resultados que el Fert II. Los medios Fert I y Fert II tienen un valor económico más bajo que el medio F/2. El crecimiento y el rendimiento fueron mejores con el medio F/2, seguido por FI y FII.

  20. Neutral lipid accumulation at elevated temperature in conditional mutants of two microalgae species

    DEFF Research Database (Denmark)

    Yao, Shuo; Brandt, Anders Bøving; Egsgaard, Helge

    2012-01-01

    Triacylglycerols, an energy storage compound in microalgae, are known to be accumulated after nitrogen starvation of microalgae cells. Microalgae could be of importance for future biodiesel production due to their fast growth rate and high oil content. In collections of temperature sensitive muta...

  1. Effect of Lignocellulose Related Compounds on Microalgae Growth and Product Biosynthesis: A Review

    OpenAIRE

    Krystian Miazek; Claire Remacle; Aurore Richel; Dorothee Goffin

    2014-01-01

    Microalgae contain valuable compounds that can be harnessed for industrial applications. Lignocellulose biomass is a plant material containing in abundance organic substances such as carbohydrates, phenolics, organic acids and other secondary compounds. As growth of microalgae on organic substances was confirmed during heterotrophic and mixotrophic cultivation, lignocellulose derived compounds can become a feedstock to cultivate microalgae and produce target compounds. In this review, differe...

  2. Microalgas, produtos e aplicações Microalgae, products and applications

    Directory of Open Access Journals (Sweden)

    Roberto Bianchini Derner

    2006-12-01

    Full Text Available Nos últimos anos, muito interesse tem sido focado no potencial biotecnológico das microalgas, principalmente devido à identificação de diversas substâncias sintetizadas por estes organismos. A imensa biodiversidade e conseqüente variabilidade na composição bioquímica da biomassa obtida das culturas microalgais, aliadas ao emprego de melhoramento genético e ao estabelecimento de tecnologia de cultivo em grande escala, vêm permitindo que determinadas espécies sejam comercialmente utilizadas. Nesse sentido, cultivos de microalgas têm sido realizados visando à produção de biomassa tanto para uso na elaboração de alimentos quanto para a obtenção de compostos naturais com alto valor no mercado mundial. Dentre os inúmeros compostos extraídos, ou com potencial de exploração comercial, podem ser relacionados ácidos graxos poliinsaturados, carotenóides, ficobilinas, polissacarídeos, vitaminas, esteróis e diversos compostos bioativos naturais (antioxidantes, redutores do colesterol etc., os quais podem ser empregados especialmente no desenvolvimento de alimentos funcionais, por suas propriedades nutricionais e farmacêuticas.In recent years, much interest has been focused on the biotechnological potential of microalgae, mainly due the identification of several substances synthesized by these organisms. The great biodiversity and consequent variability in the biochemical composition of the biomass obtained from the microalgal cultures, allied to the genetic improvement and to the establishment of technology in massive production, have allowed various species to be commercially cultivated. In this sense, microalgae cultivations have been developed aiming at the biomass production not only for use in the food elaboration but also for the obtainment of natural compounds with high value in the world market. Among the main extracted substances, or with potential of commercial exploration, can be related polyunsaturated fatty acids

  3. Nutrient and media recycling in heterotrophic microalgae cultures.

    Science.gov (United States)

    Lowrey, Joshua; Armenta, Roberto E; Brooks, Marianne S

    2016-02-01

    In order for microalgae-based processes to reach commercial production for biofuels and high-value products such as omega-3 fatty acids, it is necessary that economic feasibility be demonstrated at the industrial scale. Therefore, process optimization is critical to ensure that the maximum yield can be achieved from the most efficient use of resources. This is particularly true for processes involving heterotrophic microalgae, which have not been studied as extensively as phototrophic microalgae. An area that has received significant conceptual praise, but little experimental validation, is that of nutrient recycling, where the waste materials from prior cultures and post-lipid extraction are reused for secondary fermentations. While the concept is very simple and could result in significant economic and environmental benefits, there are some underlying challenges that must be overcome before adoption of nutrient recycling is viable at commercial scale. Even more, adapting nutrient recycling for optimized heterotrophic cultures presents some added challenges that must be identified and addressed that have been largely unexplored to date. These challenges center on carbon and nitrogen recycling and the implications of using waste materials in conjunction with virgin nutrients for secondary cultures. The aim of this review is to provide a foundation for further understanding of nutrient recycling for microalgae cultivation. As such, we outline the current state of technology and practical challenges associated with nutrient recycling for heterotrophic microalgae on an industrial scale and give recommendations for future work.

  4. Applications of microfluidics in microalgae biotechnology: A review.

    Science.gov (United States)

    Juang, Yi-Je; Chang, Jo-Shu

    2016-03-01

    Microalgae have been one of the important sources for biofuel production owing to their competitive advantages such as no need to tap into the global food supply chain, higher energy density, and absorbing carbon dioxide to mitigate global warming. One of the key factors to ensure successful biofuel production is that it requires not only bioprospecting of the microalgae with high lipid content, high growth rate and tolerance to environmental parameters but also on-site monitoring of the cultivation process and optimization of the culturing conditions. However, as the conventional techniques usually involve in complicated procedures, or are time-consuming or labor intensive, microfluidics technology offers an attractive alternative to resolve these issues. In this review, applications of microfluidics to bioprospecting in microalgae biotechnology were discussed such as cell identification, cell sorting/screening, cell culturing and cell disruption. In addition, utilization of microalgae in micro-sized fuel cells and microfluidic platforms for biosensing was addressed. This review reports the recent studies and offers a look into how microfluidics is exploited to tackle the issues encountered in the microalgae biotechnology. Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Influence of Microalgae onto submerged surfaces on Fouling

    Science.gov (United States)

    Kong, M.; Eom, C.; Yoon, B.; Yoon, H.; Kim, B.; Chung, K.

    2012-12-01

    Lots of algae together with organic matter deposited on the submerged surface can be easily observed occurring in the shallower water along the coast. This is mainly because only those organisms with the ability to adapt to the new situations created by man can firmly adhere enough to avoid being washed off. Chemical and microbiological characteristics of the fouling microalgae developed on various surfaces in contact with the seawater were made. The microbial compositions of the microalgae formed on the submerged surfaces were tested for. The quantities of the diverse microalgae in the samples developed on the prohibiting submerged surface were larger when there was no concern about materials for special selection for fouling. To confirm formation of microalgae on adsorbents was done SEM-EDS (Scanning Electron Microscope-Spectrometer) analysis. Microbial identified using optical microscope. In addition to, we quantified attaching microalgae as pass time. Experiment results, ten species which are Nitzshhia sp., Eucampia sp., Coscinodiscus sp., Licmophora sp., Rhizosolenia sp., Cylindrotheca sp., Striateela sp., Thalassionema sp., Guinardia sp., and Helicostomella sp. discovered to reservoir formed biofouling. They showed the important role microbial activity in fouling and corrosion of the surfaces in contact with the any seawater.

  6. Fuels from microalgae: Technology status, potential, and research requirements

    Energy Technology Data Exchange (ETDEWEB)

    Neenan, B.; Feinberg, D.; Hill, A.; McIntosh, R.; Terry, K.

    1986-08-01

    Although numerous options for the production of fuels from microalgae have been proposed, our analysis indicates that only two qualify for extensive development - gasoline and ester fuel. In developing the comparisons that support this conclusion, we have identified the major areas of microalgae production and processing that require extensive development. Technology success requires developing and testing processes that fully utilize the polar and nonpolar lipids produced by microalgae. Process designs used in these analyses were derived from fragmented, preliminary laboratory data. These results must be substantiated and integrated processes proposed, tested, and refined to be able to evaluate the commercial feasibility from microalgae. The production of algal feedstocks for processing to gasoline or ester fuel requires algae of high productivity and high lipid content that efficiently utilize saline waters. Species screening and development suggest that algae can achieve required standards taken individually, but algae that can meet the integrated requirements still elude researchers. Effective development of fuels from microalgae technology requires that R and D be directed toward meeting the integrated standards set out in the analysis. As technology analysts, it is inappropriate for us to dictate how the R and D effort should proceed to meet these standards. We end our role by noting that alternative approaches to meeting the feasibility targets have been identified, and it is now the task of program managers and scientists to choose the appropriate approach to assure the greatest likelihood of realizing a commercially viable technology. 70 refs., 39 figs., 35 tabs.

  7. Low-cost harvesting of microalgae biomass from water

    Directory of Open Access Journals (Sweden)

    Bejor, E.S.

    2013-03-01

    Full Text Available Microalgae harvesting is known to be a major problem in the water industry. This is attributed to the minute nature of the algae cells and the often low concentration of the species in water and wastewater. While various chemical and mechanical harvesting techniques have been developed for algae harvesting, their application have been limited by prohibitive costs. There is also the disadvantage of not utilising the harvested microalgae as feedstock when it has accumulated significant amounts of chemicals (coagulants employed during the harvesting operation. This work investigates the low cost harvesting of microalgae biomass from water using physical (non-chemical method. Four fabric filters: stretch-cotton, polyester-linen, satin-polyester and silk were investigated to determine their microalgae harvesting efficiencies using filtration method on three algae communities with cell size of 2- 20 µm. For the three algae communities investigated, stretch-cotton filter showed a harvesting efficiency of 66- 93%, followed by polyester-linen (54- 90%, while satin-polyester and silk fabrics achieved harvesting efficiencies of 43- 71% and 27- 75% respectively. The research revealed that for wastewater generation of 1500m3/day and algae concentration of 200mg/l, microalgae harvesting cost per sq. meter per kg of algae per cubic meter would be ≤ £0.15 using stretch cotton filter

  8. Isolation, identification and characterization of an electrogenic microalgae strain.

    Directory of Open Access Journals (Sweden)

    Yicheng Wu

    Full Text Available Extracellular electron transfer involving microbes is important as it closely reflects the ability of cells to communicate with the environment. However, there are few reports on electron transfer mechanisms of pure microalgae and a lack of any model alga to study the transfer processes. In the present study, nine green microalgae species were isolated from wastewater and characterized in terms of their ability to transfer electrons between cells and an electrode. One species showed direct electron transfer via membrane-associated proteins and indirect electron transfer via secreted oxygen. The microalga was identified as Desmodesmus sp. based on phylogenetic analysis and electron microscopy. Electrochemical tests demonstrated that Desmodesmus sp. was able to act as a cathodic microorganism. Stable current densities of -0.24, 35.54 and 170 mA m(-2 were achieved at potentials of +0.2, -0.2 and -0.4 V, respectively, under illumination. Dissolved oxygen concentration measurement showed gradients within the microalgae biofilm: 18.3 mg L(-1 in light decreasing to 4.29 mg L(-1 in the dark. This study diversified the exoelectrogen library and provided a potential model microalga to explore the associated mechanism of extracellular electron transfer.

  9. Extracellular Metabolites from Industrial Microalgae and Their Biotechnological Potential

    Directory of Open Access Journals (Sweden)

    Lu Liu

    2016-10-01

    Full Text Available Industrial microalgae, as a big family of promising producers of renewable biomass feedstock, have been commercially exploited for functional food, living feed and feed additives, high-value chemicals in nutraceuticals, cosmeceuticals, and chemical reagents. Recently, microalgae have also been considered as a group that might play an important role in biofuel development and environmental protection. Almost all current products of industrial microalgae are derived from their biomass; however, large amounts of spent cell-free media are available from mass cultivation that is mostly unexploited. In this contribution we discuss that these media, which may contain a remarkable diversity of bioactive substances are worthy to be recovered for further use. Obviously, the extracellular metabolites from industrial microalgae have long been neglected in the development of production methods for valuable metabolites. With the advances in the last ten years, more and more structures and properties from extracellular metabolites have been identified, and the potential utilization over wide fields is attracting attention. Some of these extracellular metabolites can be potentially used as drugs, antioxidants, growth regulators or metal chelators. The purpose of this review is to provide an overview of the known extracellular metabolites from industrial microalgae which might be of commercial interest. The attention mainly focuses on the reports of extracellular bioactive metabolites and their potential application in biotechnology.

  10. Extracellular Metabolites from Industrial Microalgae and Their Biotechnological Potential.

    Science.gov (United States)

    Liu, Lu; Pohnert, Georg; Wei, Dong

    2016-10-20

    Industrial microalgae, as a big family of promising producers of renewable biomass feedstock, have been commercially exploited for functional food, living feed and feed additives, high-value chemicals in nutraceuticals, cosmeceuticals, and chemical reagents. Recently, microalgae have also been considered as a group that might play an important role in biofuel development and environmental protection. Almost all current products of industrial microalgae are derived from their biomass; however, large amounts of spent cell-free media are available from mass cultivation that is mostly unexploited. In this contribution we discuss that these media, which may contain a remarkable diversity of bioactive substances are worthy to be recovered for further use. Obviously, the extracellular metabolites from industrial microalgae have long been neglected in the development of production methods for valuable metabolites. With the advances in the last ten years, more and more structures and properties from extracellular metabolites have been identified, and the potential utilization over wide fields is attracting attention. Some of these extracellular metabolites can be potentially used as drugs, antioxidants, growth regulators or metal chelators. The purpose of this review is to provide an overview of the known extracellular metabolites from industrial microalgae which might be of commercial interest. The attention mainly focuses on the reports of extracellular bioactive metabolites and their potential application in biotechnology.

  11. Monitoring Growth and Lipid Production of Some Egyptian Microalgae

    International Nuclear Information System (INIS)

    El-Baghdady, K.Z.; Zakaria, A.E.; Mousa, L.A.; Sadek, H.N.; Abd El Fatah, H.M.

    2016-01-01

    Microalgae bio diesel is a green and renewable energy resource. This study aims to examine growth and lipid production by various isolates of icroalgae using different growth media and lipid extraction techniques. Ten microalgae isolates were isolated from different samples collected from Egypt. The purified isolates were identified microscopically as: Lyngbya confervoides, Phormidium bohneri, Oscillatoria pseudogeminata, Amorphonostoc sp., Nostoc paludosum, Anabaena sphaerica related to cyanobacteria (blue green algae) and Chlorella vulgaris, Chlorella ellipsoidea, Scened esmusacutus acutus, Chlamydomonas globose related to green algae. These organisms were cultivated on two media: Bold's Basal Medium(BBM medium) and Blue Green Medium (BG-11 medium) to examine the favorite medium which supports the growth of each isolate In order to examine lipid production potentials by cyanobacterial isolates and green microalgae, two solvent systems were applied for lipid extraction, the first was (Chloroform - methanol 1:1 ) and the second was (Hexane-ethanol 1:1). Chlorella vulgaris and Anabaena sphaerica were selected as models of green microalgae and cyanobacteria espectively. Hexane-ethanol solvent system revealed higher lipid extraction capacity as compared to Chloroform- methanol system. A comparison between ten organisms for lipid production was carried out by the selected solvent mixture. The percentages of lipid to dry weight produced by Oscillatoria pseudogeminata and Chlamydomonas globose were 19.8% and14 .6% respectively recording the highest lipid to dry weight percentage. They can be considered as a promising lipid producing microalgae

  12. [A novel flat plate photobioreactor for microalgae cultivation].

    Science.gov (United States)

    Zhang, Qinghua; Yan, Chenghu; Xue, Shengzhang; Wu, Xia; Wang, Zhihui; Cong, Wei

    2015-02-01

    Flashing light effect on microalgae could significantly improve the light efficiency and biomass productivity of microalgae. In this paper, the baffles were introduced into the traditional flat plate photobioreactor so as to enhance the flashing light effect of microalgae. Making Chlorella sp. as the model microalgae, the effect of light intensity and inlet velocity on the biomass concentration of Chlorella sp. and light efficiency were evaluated. The results showed that, when the inlet velocity was 0.16 m/s, with the increase of light intensity, the cell dry weight of Chlorella sp. increased and light efficiency decreased. With increasing the inlet velocity, the cell dry weight of Chlorella sp. and light efficiency both increased under the condition of 500 μmol/(m2 x s) light intensity. The cell dry weight of Chlorella sp. cultivated in the novel flat plate photobioreactor was 39.23% higher than that of the traditional one, which showed that the flashing light effect of microalgae could be improved in the flat plate photobioreactor with inclined baffles built-in.

  13. Extracellular Metabolites from Industrial Microalgae and Their Biotechnological Potential

    Science.gov (United States)

    Liu, Lu; Pohnert, Georg; Wei, Dong

    2016-01-01

    Industrial microalgae, as a big family of promising producers of renewable biomass feedstock, have been commercially exploited for functional food, living feed and feed additives, high-value chemicals in nutraceuticals, cosmeceuticals, and chemical reagents. Recently, microalgae have also been considered as a group that might play an important role in biofuel development and environmental protection. Almost all current products of industrial microalgae are derived from their biomass; however, large amounts of spent cell-free media are available from mass cultivation that is mostly unexploited. In this contribution we discuss that these media, which may contain a remarkable diversity of bioactive substances are worthy to be recovered for further use. Obviously, the extracellular metabolites from industrial microalgae have long been neglected in the development of production methods for valuable metabolites. With the advances in the last ten years, more and more structures and properties from extracellular metabolites have been identified, and the potential utilization over wide fields is attracting attention. Some of these extracellular metabolites can be potentially used as drugs, antioxidants, growth regulators or metal chelators. The purpose of this review is to provide an overview of the known extracellular metabolites from industrial microalgae which might be of commercial interest. The attention mainly focuses on the reports of extracellular bioactive metabolites and their potential application in biotechnology. PMID:27775594

  14. Microalgae cultivation in sugarcane vinasse: Selection, growth and biochemical characterization.

    Science.gov (United States)

    Santana, Hugo; Cereijo, Carolina R; Teles, Valérya C; Nascimento, Rodrigo C; Fernandes, Maiara S; Brunale, Patrícia; Campanha, Raquel C; Soares, Itânia P; Silva, Flávia C P; Sabaini, Priscila S; Siqueira, Félix G; Brasil, Bruno S A F

    2017-03-01

    Sugarcane ethanol is produced at large scale generating wastes that could be used for microalgae biomass production in a biorefinery strategy. In this study, forty microalgae strains were screened for growth in sugarcane vinasse at different concentrations. Two microalgae strains, Micractinium sp. Embrapa|LBA32 and C. biconvexa Embrapa|LBA40, presented vigorous growth in a light-dependent manner even in undiluted vinasse under non-axenic conditions. Microalgae strains presented higher biomass productivity in vinasse-based media compared to standard Bold's Basal Medium in cultures performed using 15L airlift flat plate photobioreactors. Chemical composition analyses showed that proteins and carbohydrates comprise the major fractions of algal biomass. Glucose was the main monosaccharide detected, ranging from 46% to 76% of the total carbohydrates content according to the strain and culture media used. This research highlights the potential of using residues derived from ethanol plants to cultivate microalgae for the production of energy and bioproducts. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. BIOREMOVAL OF LEAD IN INDUSTRIAL WASTEWATER BY MICROALGAE

    Directory of Open Access Journals (Sweden)

    M. RANITHA

    2016-07-01

    Full Text Available The removal of heavy metals from our environment especially wastewater is now shifting from the use of conventional removal method such as chemical precipitation, coagulation and membrane filtration to the use of bioremoval method. The presence of heavy metals in the environment is of major concern because of their toxicity, bioaccumulating tendency, and threat to human life and the environment. In recent years, many low cost sorbents such as microalgae, fungi bacteria and lignocellulosic agricultural by-products have been investigated for their biosorption capacity towards heavy metals. In this project, the focus is on bioremoval of heavy metals in wastewater using marine microalgae. The study will be emphasize on the efficiency of two marine microalgae named Nannochloropsis oculata and Tetraselmis chuii in treating the Lead (Pb content in industrial wasterwater. An experiment on the effect of various Pb concentration (10/20/40/60/80/100mg/L towards the microalgae has been studied. The obtained result showed that the content of chlorophyll-A in the microalgae sample, after 7 days of exposures to Pb, decreased as the Pb concentration increased. Besides that, Tetraselmis chuii was found to be more sensitive compared to Nannochloropsis oculata where both were able to tolerate the Pb concentration of up to only 20mg/L and 60mg/L, respectively.

  16. Acidified-flocculation process for harvesting of microalgae: Coagulant reutilization and metal-free-microalgae recovery.

    Science.gov (United States)

    Kim, Dong-Yeon; Lee, Kyubock; Lee, Jiye; Lee, Young-Hee; Han, Jong-In; Park, Ji-Yeon; Oh, You-Kwan

    2017-09-01

    Chemical flocculation is considered to be an overall low-cost and up-scalable process for harvesting of microalgae. In this study a new flocculation approach utilizing metal coagulant (Fe 2 (SO 4 ) 3 ) and sulfuric acid (H 2 SO 4 ) was introduced for harvesting of Chlorella sp. KR-1, which overcome two main issues of contamination and reuse of coagulant. Reduction of pH successfully released precipitates attached to the microalgae, and the remaining acidic solution containing recovered ferric ions could be reused for harvesting up to three times with high, better-than 98% efficiencies. Moreover, the acid-treated microalgal biomass could be directly used for lipid extraction without additional catalyst. High extraction yields of around 32% were achieved with FAME conversion efficiencies of around 90%. The integrated approach devised in the present study is expected to make the best use of the age-old yet effective harvesting means of flocculation, which can be a practical and economical option in microalgal biorefinery. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Safety assessment of the microalgae Nannochloropsis oculata

    Directory of Open Access Journals (Sweden)

    Michael L. Kagan

    2015-01-01

    Full Text Available Nannochloropsis oculata is a marine-water microalgae that is considered to be a good source of omega-3 fatty acids, specifically eicosapentaenoic acid (EPA, utilized in the production of an omega-3 oil for use as a dietary supplement. This study investigates the safety of N. oculata in male and female Sprague-Dawley rats administered a 0 or 10 mL/kg bw/rat N. oculata (10E8 viable cells/mL suspension by oral gavage once daily for 14 consecutive days. No mortalities occurred and no signs of toxicity were observed during the study. No treatment-related effects were seen for body weight, food consumption, urinalysis, clinical chemistry, hematology, gross pathology, organ weights, or histopathology. Although statistically significant effects were noted for some endpoints, none were considered to be of toxicological significance. The N. oculata suspension was concluded to have no toxicity in rats, confirming that the algal strain used in the production of omega-3 oil is not pathogenic when administered orally to rats.

  18. Growth of microalgae in autotrophic stationary systems

    Directory of Open Access Journals (Sweden)

    Paulo Cunha

    2008-06-01

    Full Text Available In this paper we evaluate the growth of nine marine microalgae species (Nannochloropsis oculata, Thalassiosira pseudonana, Phaeodactylum tricornutum, Isochrysis galbana, Tetraselmis suecica, Tetraselmis chuii, Chaetoceros muelleri, Thalassiosira fluviatilis and Isochrysis sp. and one freshwater species (Chlorella vulgaris under stationary autotrophy conditions, using erlenmeyers fl asks with 800mL of culture medium exposed to constant light intensities providing a photon flux density of about 150μmol.m-2.s-1 and 25±2oC temperature and constant air flow. The experiment was carried out in a controlled environment considering a block delineating randomized over time with three replicates. The Nannochloropsis oculata showed the highest value of maximum cellular density, but with a longer period of time and a lower growth rate. This was probably due to its tiny cell size, demanding a large number of cells per volume to attain its optimum conditions for light, nutrients, water and atmospheric carbon dioxide. In addition, in spite of showing one of the lowest values of maximum cellular density, Thalassiosira fluviatilis was the species that reached its maximum in a short period of time at the highest growth rate. Chlorella vulgaris was the only freshwater species tested and it showed the poorest performance for all the variables analyzed in the current study.

  19. Safety assessment of the microalgae Nannochloropsis oculata.

    Science.gov (United States)

    Kagan, Michael L; Matulka, Ray A

    2015-01-01

    Nannochloropsis oculata is a marine-water microalgae that is considered to be a good source of omega-3 fatty acids, specifically eicosapentaenoic acid (EPA), utilized in the production of an omega-3 oil for use as a dietary supplement. This study investigates the safety of N. oculata in male and female Sprague-Dawley rats administered a 0 or 10 mL/kg bw/rat N. oculata (10E8 viable cells/mL) suspension by oral gavage once daily for 14 consecutive days. No mortalities occurred and no signs of toxicity were observed during the study. No treatment-related effects were seen for body weight, food consumption, urinalysis, clinical chemistry, hematology, gross pathology, organ weights, or histopathology. Although statistically significant effects were noted for some endpoints, none were considered to be of toxicological significance. The N. oculata suspension was concluded to have no toxicity in rats, confirming that the algal strain used in the production of omega-3 oil is not pathogenic when administered orally to rats.

  20. Nitrogen Removal from Landfill Leachate by Microalgae

    Science.gov (United States)

    Pereira, Sérgio F. L.; Gonçalves, Ana L.; Moreira, Francisca C.; Silva, Tânia F. C. V.; Vilar, Vítor J. P.; Pires, José C. M.

    2016-01-01

    Landfill leachates result from the degradation of solid residues in sanitary landfills, thus presenting a high variability in terms of composition. Normally, these effluents are characterized by high ammoniacal-nitrogen (N–NH4+) concentrations, high chemical oxygen demands and low phosphorus concentrations. The development of effective treatment strategies becomes difficult, posing a serious problem to the environment. Phycoremediation appears to be a suitable alternative for the treatment of landfill leachates. In this study, the potential of Chlorella vulgaris for biomass production and nutrients (mainly nitrogen and phosphorus) removal from different compositions of a landfill leachate was evaluated. Since microalgae also require phosphorus for their growth, different loads of this nutrient were evaluated, giving the following N:P ratios: 12:1, 23:1 and 35:1. The results have shown that C. vulgaris was able to grow in the different leachate compositions assessed. However, microalgal growth was higher in the cultures presenting the lowest N–NH4+ concentration. In terms of nutrients uptake, an effective removal of N–NH4+ and phosphorus was observed in all the experiments, especially in those supplied with phosphorus. Nevertheless, N–NO3− removal was considered almost negligible. These promising results constitute important findings in the development of a bioremediation technology for the treatment of landfill leachates. PMID:27869676

  1. Microalgae as bioreactors for bioplastic production

    Directory of Open Access Journals (Sweden)

    Steinbüchel Alexander

    2011-10-01

    Full Text Available Abstract Background Poly-3-hydroxybutyrate (PHB is a polyester with thermoplastic properties that is naturally occurring and produced by such bacteria as Ralstonia eutropha H16 and Bacillus megaterium. In contrast to currently utilized plastics and most synthetic polymers, PHB is biodegradable, and its production is not dependent on fossil resources making this bioplastic interesting for various industrial applications. Results In this study, we report on introducing the bacterial PHB pathway of R. eutropha H16 into the diatom Phaeodactylum tricornutum, thereby demonstrating for the first time that PHB production is feasible in a microalgal system. Expression of the bacterial enzymes was sufficient to result in PHB levels of up to 10.6% of algal dry weight. The bioplastic accumulated in granule-like structures in the cytosol of the cells, as shown by light and electron microscopy. Conclusions Our studies demonstrate the great potential of microalgae like the diatom P. tricornutum to serve as solar-powered expression factories and reveal great advantages compared to plant based production systems.

  2. Microalgae as bioreactors for bioplastic production.

    Science.gov (United States)

    Hempel, Franziska; Bozarth, Andrew S; Lindenkamp, Nicole; Klingl, Andreas; Zauner, Stefan; Linne, Uwe; Steinbüchel, Alexander; Maier, Uwe G

    2011-10-17

    Poly-3-hydroxybutyrate (PHB) is a polyester with thermoplastic properties that is naturally occurring and produced by such bacteria as Ralstonia eutropha H16 and Bacillus megaterium. In contrast to currently utilized plastics and most synthetic polymers, PHB is biodegradable, and its production is not dependent on fossil resources making this bioplastic interesting for various industrial applications. In this study, we report on introducing the bacterial PHB pathway of R. eutropha H16 into the diatom Phaeodactylum tricornutum, thereby demonstrating for the first time that PHB production is feasible in a microalgal system. Expression of the bacterial enzymes was sufficient to result in PHB levels of up to 10.6% of algal dry weight. The bioplastic accumulated in granule-like structures in the cytosol of the cells, as shown by light and electron microscopy. Our studies demonstrate the great potential of microalgae like the diatom P. tricornutum to serve as solar-powered expression factories and reveal great advantages compared to plant based production systems.

  3. Nitrogen Removal from Landfill Leachate by Microalgae.

    Science.gov (United States)

    Pereira, Sérgio F L; Gonçalves, Ana L; Moreira, Francisca C; Silva, Tânia F C V; Vilar, Vítor J P; Pires, José C M

    2016-11-17

    Landfill leachates result from the degradation of solid residues in sanitary landfills, thus presenting a high variability in terms of composition. Normally, these effluents are characterized by high ammoniacal-nitrogen (N-NH₄⁺) concentrations, high chemical oxygen demands and low phosphorus concentrations. The development of effective treatment strategies becomes difficult, posing a serious problem to the environment. Phycoremediation appears to be a suitable alternative for the treatment of landfill leachates. In this study, the potential of Chlorella vulgaris for biomass production and nutrients (mainly nitrogen and phosphorus) removal from different compositions of a landfill leachate was evaluated. Since microalgae also require phosphorus for their growth, different loads of this nutrient were evaluated, giving the following N:P ratios: 12:1, 23:1 and 35:1. The results have shown that C. vulgaris was able to grow in the different leachate compositions assessed. However, microalgal growth was higher in the cultures presenting the lowest N-NH₄⁺ concentration. In terms of nutrients uptake, an effective removal of N-NH₄⁺ and phosphorus was observed in all the experiments, especially in those supplied with phosphorus. Nevertheless, N-NO₃ - removal was considered almost negligible. These promising results constitute important findings in the development of a bioremediation technology for the treatment of landfill leachates.

  4. Nitrogen Removal from Landfill Leachate by Microalgae

    Directory of Open Access Journals (Sweden)

    Sérgio F. L. Pereira

    2016-11-01

    Full Text Available Landfill leachates result from the degradation of solid residues in sanitary landfills, thus presenting a high variability in terms of composition. Normally, these effluents are characterized by high ammoniacal-nitrogen (N–NH4+ concentrations, high chemical oxygen demands and low phosphorus concentrations. The development of effective treatment strategies becomes difficult, posing a serious problem to the environment. Phycoremediation appears to be a suitable alternative for the treatment of landfill leachates. In this study, the potential of Chlorella vulgaris for biomass production and nutrients (mainly nitrogen and phosphorus removal from different compositions of a landfill leachate was evaluated. Since microalgae also require phosphorus for their growth, different loads of this nutrient were evaluated, giving the following N:P ratios: 12:1, 23:1 and 35:1. The results have shown that C. vulgaris was able to grow in the different leachate compositions assessed. However, microalgal growth was higher in the cultures presenting the lowest N–NH4+ concentration. In terms of nutrients uptake, an effective removal of N–NH4+ and phosphorus was observed in all the experiments, especially in those supplied with phosphorus. Nevertheless, N–NO3− removal was considered almost negligible. These promising results constitute important findings in the development of a bioremediation technology for the treatment of landfill leachates.

  5. Antioxidant activity of the microalga Spirulina maxima

    Directory of Open Access Journals (Sweden)

    M.S. Miranda

    1998-08-01

    Full Text Available Spirulina maxima, which is used as a food additive, is a microalga rich in protein and other essential nutrients. Spirulina contains phenolic acids, tocopherols and ß-carotene which are known to exhibit antioxidant properties. The aim of the present study was to evaluate the antioxidant capacity of a Spirulina extract. The antioxidant activity of a methanolic extract of Spirulina was determined in vitro and in vivo. The in vitro antioxidant capacity was tested on a brain homogenate incubated with and without the extract at 37oC. The IC50 (concentration which causes a 50% reduction of oxidation of the extract in this system was 0.18 mg/ml. The in vivo antioxidant capacity was evaluated in plasma and liver of animals receiving a daily dose of 5 mg for 2 and 7 weeks. Plasma antioxidant capacity was measured in brain homogenate incubated for 1 h at 37oC. The production of oxidized compounds in liver after 2 h of incubation at 37oC was measured in terms of thiobarbituric acid reactant substances (TBARS in control and experimental groups. Upon treatment, the antioxidant capacity of plasma was 71% for the experimental group and 54% for the control group. Data from liver spontaneous peroxidation studies were not significantly different between groups. The amounts of phenolic acids, a-tocopherol and ß-carotene were determined in Spirulina extracts. The results obtained indicate that Spirulina provides some antioxidant protection for both in vitro and in vivo systems.

  6. The Water to Water Cycles in Microalgae.

    Science.gov (United States)

    Curien, Gilles; Flori, Serena; Villanova, Valeria; Magneschi, Leonardo; Giustini, Cécile; Forti, Giorgio; Matringe, Michel; Petroutsos, Dimitris; Kuntz, Marcel; Finazzi, Giovanni

    2016-07-01

    In oxygenic photosynthesis, light produces ATP plus NADPH via linear electron transfer, i.e. the in-series activity of the two photosystems: PSI and PSII. This process, however, is thought not to be sufficient to provide enough ATP per NADPH for carbon assimilation in the Calvin-Benson-Bassham cycle. Thus, it is assumed that additional ATP can be generated by alternative electron pathways. These circuits produce an electrochemical proton gradient without NADPH synthesis, and, although they often represent a small proportion of the linear electron flow, they could have a huge importance in optimizing CO 2 assimilation. In Viridiplantae, there is a consensus that alternative electron flow comprises cyclic electron flow around PSI and the water to water cycles. The latter processes include photosynthetic O 2 reduction via the Mehler reaction at PSI, the plastoquinone terminal oxidase downstream of PSII, photorespiration (the oxygenase activity of Rubisco) and the export of reducing equivalents towards the mitochondrial oxidases, through the malate shuttle. In this review, we summarize current knowledge about the role of the water to water cycles in photosynthesis, with a special focus on their occurrence and physiological roles in microalgae. © 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.

  7. Gold nanoparticles produced in a microalga

    International Nuclear Information System (INIS)

    Luangpipat, Tiyaporn; Beattie, Isabel R.; Chisti, Yusuf; Haverkamp, Richard G.

    2011-01-01

    An efficient biological route to production of gold nanoparticles which allows the nanoparticles to be easily recovered remains elusive. Live cells of the green microalga Chlorella vulgaris were incubated with a solution of gold chloride and harvested by centrifugation. Nanoparticles inside intact cells were identified by transmission electron microscopy and confirmed to be metallic gold by synchrotron based X-ray powder diffraction and X-ray absorption spectroscopy. These intracellular gold nanoparticles were 40–60 nm in diameter. At a concentration of 1.4% Au in the alga, a better than 97% recovery of the gold from solution was achieved. A maximum of 4.2% Au in the alga was obtained. Exposure of C. vulgaris to solutions containing dissolved salts of palladium, ruthenium, and rhodium also resulted in the production of the corresponding nanoparticles within the cells. These were surmised to be also metallic, but were produced at a much lower intracellular concentration than achieved with gold. Iridium was apparently toxic to the alga. No nanoparticles were observed using platinum solutions. C. vulgaris provides a possible route to large scale production of gold nanoparticles.

  8. Microalgae Culture Collection, 1985-1986

    Energy Technology Data Exchange (ETDEWEB)

    1986-01-01

    The SERI Microalgae Culture Collection was established in support of the US Department of Energy's Biofuels Program to provide a repository for strains identified or developed for mass culture biomass production and to make these strains readily available to the research community. The strains in the collection have been selected for their potential in biomass fuel applications, and many produce significant quantities of cellular storage lipids. The Culture Collection Catalog lists 20 strains of ten species. Many have been tested in outdoor mass culture systems, and several have demonstrated excellent performance as biomass producers, with yields of up to 40 grams of organic matter per square meter per day. The majority of strains added to the collection this year have been isolated from inland saline waters, although marine species are included as well. We believe that the strains in this collection can provide a source of extremely useful organisms, both for laboratory experimentation and for mass culture research. 98 refs., 31 figs., 52 tabs.

  9. Microalgae culture collection, 1986-1987

    Energy Technology Data Exchange (ETDEWEB)

    Barclay, W.; Johansen, J.; Chelf, P.; Nagle, N.; Roessler, P.; Lemke, P.

    1986-12-01

    The SERI Microalgae Culture Collection provides a repository for strains identified or developed for mass culture biomass production and makes these strains readily available to the research community. The strains in the collection have been selected for their potential in biomass fuel applications, and many produce significant quantities of cellular storage lipids. All of the newly added strains have been recently isolated by SERI and its subcontractors in organized screening programs. Many have been tested in outdoor mass culture systems, and several have demonstrated excellent performance as biomass producers. The strains added to the collection this year have been isolated from inland saline waters and marine waters. We believe that the strains in this collection can provide a source of extremely useful organisms, both for laboratory experimentation and for mass culture research. Most of the strains are currently nonaxenic. Again this year, cultures will be shipped free of charge to interested researchers. An important function of the culture collection catalog, in addition to listing the available strains, is to provide culture and performance data for each of the organisms. By collecting a summary of the requirements and characteristics of these organisms, we hope to allow requestors of cultures to begin productive research with a minimum of preliminary work on culture techniques.

  10. Advances in Microalgae-Derived Phytosterols for Functional Food and Pharmaceutical Applications.

    Science.gov (United States)

    Luo, Xuan; Su, Peng; Zhang, Wei

    2015-07-09

    Microalgae contain a variety of bioactive lipids with potential applications in aquaculture feed, biofuel, food and pharmaceutical industries. While microalgae-derived polyunsaturated fatty acid (PUFA) and their roles in promoting human health have been extensively studied, other lipid types from this resource, such as phytosterols, have been poorly explored. Phytosterols have been used as additives in many food products such as spread, dairy products and salad dressing. This review focuses on the recent advances in microalgae-derived phytosterols with functional bioactivities and their potential applications in functional food and pharmaceutical industries. It highlights the importance of microalgae-derived lipids other than PUFA for the development of an advanced microalgae industry.

  11. Bioactivity and Applications of Sulphated Polysaccharides from Marine Microalgae

    Directory of Open Access Journals (Sweden)

    Rui Manuel Santos Costa de Morais

    2013-01-01

    Full Text Available Marine microalgae have been used for a long time as food for humans, such as Arthrospira (formerly, Spirulina, and for animals in aquaculture. The biomass of these microalgae and the compounds they produce have been shown to possess several biological applications with numerous health benefits. The present review puts up-to-date the research on the biological activities and applications of polysaccharides, active biocompounds synthesized by marine unicellular algae, which are, most of the times, released into the surrounding medium (exo- or extracellular polysaccharides, EPS. It goes through the most studied activities of sulphated polysaccharides (sPS or their derivatives, but also highlights lesser known applications as hypolipidaemic or hypoglycaemic, or as biolubricant agents and drag-reducers. Therefore, the great potentials of sPS from marine microalgae to be used as nutraceuticals, therapeutic agents, cosmetics, or in other areas, such as engineering, are approached in this review.

  12. Bioelectrochemical systems using microalgae - A concise research update.

    Science.gov (United States)

    Saratale, Rijuta Ganesh; Kuppam, Chandrasekar; Mudhoo, Ackmez; Saratale, Ganesh Dattatraya; Periyasamy, Sivagurunathan; Zhen, Guangyin; Koók, László; Bakonyi, Péter; Nemestóthy, Nándor; Kumar, Gopalakrishnan

    2017-06-01

    Excess consumption of energy by humans is compounded by environmental pollution, the greenhouse effect and climate change impacts. Current developments in the use of algae for bioenergy production offer several advantages. Algal biomass is hence considered a new bio-material which holds the promise to fulfil the rising demand for energy. Microalgae are used in effluents treatment, bioenergy production, high value added products synthesis and CO 2 capture. This review summarizes the potential applications of algae in bioelectrochemically mediated oxidation reactions in fully biotic microbial fuel cells for power generation and removal of unwanted nutrients. In addition, this review highlights the recent developments directed towards developing different types of microalgae MFCs. The different process factors affecting the performance of microalgae MFC system and some technological bottlenecks are also addressed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Ultrasonic assisted biodiesel production of microalgae by direct transesterification

    Science.gov (United States)

    Kalsum, Ummu; Mahfud, Mahfud; Roesyadi, Achmad

    2017-03-01

    Microalgae are considered as the third generation source of biofuel and an excellent candidate for biofuel production to replace the fossil energy. The use of ultrasonic in producing biodiesel by direct transesterification of Nannochloropsis occulata using KOH as catalyst and methanol as a solvent was investigated. The following condition were determined as an optimum by experimental evaluates:: 1: 15 microalga to methanol (molar ratio); 3% catalyst concentration at temperature 40°C after 30 minute of ultrasonication. The highest yield of biodiesel produced was 30.3%. The main components of methyl ester from Nannochloropsis occulata were palmitic (C16 :0),, oleic (C18:1), stearic (C18;0), arahidic (C20:0) and myristic (C14:0). This stated that the application of ultrasounic for direct transesterificaiton of microalgae effectively reduced the reaction time compared to the reported values of conventional heating systems.

  14. Microalga propels along vorticity direction in a shear flow

    Science.gov (United States)

    Chengala, Anwar; Hondzo, Miki; Sheng, Jian

    2013-05-01

    Using high-speed digital holographic microscopy and microfluidics, we discover that, when encountering fluid flow shear above a threshold, unicellular green alga Dunaliella primolecta migrates unambiguously in the cross-stream direction that is normal to the plane of shear and coincides with the local fluid flow vorticity. The flow shear drives motile microalgae to collectively migrate in a thin two-dimensional horizontal plane and consequently alters the spatial distribution of microalgal cells within a given suspension. This shear-induced algal migration differs substantially from periodic rotational motion of passive ellipsoids, known as Jeffery orbits, as well as gyrotaxis by bottom-heavy swimming microalgae in a shear flow due to the subtle interplay between torques generated by gravity and viscous shear. Our findings could facilitate mechanistic solutions for modeling planktonic thin layers and sustainable cultivation of microalgae for human nutrition and bioenergy feedstock.

  15. A Holistic Approach to Managing Microalgae for Biofuel Applications

    Directory of Open Access Journals (Sweden)

    Pau Loke Show

    2017-01-01

    Full Text Available Microalgae contribute up to 60% of the oxygen content in the Earth’s atmosphere by absorbing carbon dioxide and releasing oxygen during photosynthesis. Microalgae are abundantly available in the natural environment, thanks to their ability to survive and grow rapidly under harsh and inhospitable conditions. Microalgal cultivation is environmentally friendly because the microalgal biomass can be utilized for the productions of biofuels, food and feed supplements, pharmaceuticals, nutraceuticals, and cosmetics. The cultivation of microalgal also can complement approaches like carbon dioxide sequestration and bioremediation of wastewaters, thereby addressing the serious environmental concerns. This review focuses on the factors affecting microalgal cultures, techniques adapted to obtain high-density microalgal cultures in photobioreactors, and the conversion of microalgal biomass into biofuels. The applications of microalgae in carbon dioxide sequestration and phycoremediation of wastewater are also discussed.

  16. Microalgae as source of biofuel: technology and prospective

    Science.gov (United States)

    Ferraro, Angelo

    2017-12-01

    Microalgae are autotrophic organisms found in solitary cells or in groups of single cells connected together. Their natural environment are typically freshwater and marine systems. Microalgae produce, via photosynthesis, approximately one-half of oxygen generated on earth while simultaneously consume carbon dioxide (CO2). Among the technologies being examined to produce green fuels (e.g. biodiesel, bioethanol and syngas), microalgae are viewed by many in the scientific community as having the greatest potential to become economically viable fuels. Nevertheless, to reach economic parity with fossil fuels there are still several challenges to be tackle. These include improving harvesting and oil extraction processes as well as increasing biomass productivity and oil content. All of these challenges can be impacted by genetic, molecular, and ultimately synthetic biology techniques.

  17. Cultivation Of Microalgae (Chlorella vulgaris For Biodiesel Production

    Directory of Open Access Journals (Sweden)

    Blinová Lenka

    2015-06-01

    Full Text Available Production of biofuel from renewable sources is considered to be one of the most sustainable alternatives to petroleum sourced fuels. Biofuels are also viable means of environmental and economic sustainability. Biofuels are divided into four generations, depending on the type of biomass used for biofuels production. At present, microalgae are presented as an ideal third generation biofuel feedstock because of their rapid growth rate. They also do not compete with food or feed crops, and can be produced on non-arable land. Cultivation conditions (temperature, pH, light, nutrient quantity and quality, salinity, aerating are the major factors that influence photosynthesis activity and behaviour of the microalgae growth rate. In this paper, we present an overview about the effect of cultivation conditions on microalgae growth.

  18. Cultivation Of Microalgae (Chlorella vulgaris) For Biodiesel Production

    Science.gov (United States)

    Blinová, Lenka; Bartošová, Alica; Gerulová, Kristína

    2015-06-01

    Production of biofuel from renewable sources is considered to be one of the most sustainable alternatives to petroleum sourced fuels. Biofuels are also viable means of environmental and economic sustainability. Biofuels are divided into four generations, depending on the type of biomass used for biofuels production. At present, microalgae are presented as an ideal third generation biofuel feedstock because of their rapid growth rate. They also do not compete with food or feed crops, and can be produced on non-arable land. Cultivation conditions (temperature, pH, light, nutrient quantity and quality, salinity, aerating) are the major factors that influence photosynthesis activity and behaviour of the microalgae growth rate. In this paper, we present an overview about the effect of cultivation conditions on microalgae growth.

  19. A Holistic Approach to Managing Microalgae for Biofuel Applications.

    Science.gov (United States)

    Show, Pau Loke; Tang, Malcolm S Y; Nagarajan, Dillirani; Ling, Tau Chuan; Ooi, Chien-Wei; Chang, Jo-Shu

    2017-01-22

    Microalgae contribute up to 60% of the oxygen content in the Earth's atmosphere by absorbing carbon dioxide and releasing oxygen during photosynthesis. Microalgae are abundantly available in the natural environment, thanks to their ability to survive and grow rapidly under harsh and inhospitable conditions. Microalgal cultivation is environmentally friendly because the microalgal biomass can be utilized for the productions of biofuels, food and feed supplements, pharmaceuticals, nutraceuticals, and cosmetics. The cultivation of microalgal also can complement approaches like carbon dioxide sequestration and bioremediation of wastewaters, thereby addressing the serious environmental concerns. This review focuses on the factors affecting microalgal cultures, techniques adapted to obtain high-density microalgal cultures in photobioreactors, and the conversion of microalgal biomass into biofuels. The applications of microalgae in carbon dioxide sequestration and phycoremediation of wastewater are also discussed.

  20. Bioactivity and Applications of Sulphated Polysaccharides from Marine Microalgae

    Science.gov (United States)

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

    2013-01-01

    Marine microalgae have been used for a long time as food for humans, such as Arthrospira (formerly, Spirulina), and for animals in aquaculture. The biomass of these microalgae and the compounds they produce have been shown to possess several biological applications with numerous health benefits. The present review puts up-to-date the research on the biological activities and applications of polysaccharides, active biocompounds synthesized by marine unicellular algae, which are, most of the times, released into the surrounding medium (exo- or extracellular polysaccharides, EPS). It goes through the most studied activities of sulphated polysaccharides (sPS) or their derivatives, but also highlights lesser known applications as hypolipidaemic or hypoglycaemic, or as biolubricant agents and drag-reducers. Therefore, the great potentials of sPS from marine microalgae to be used as nutraceuticals, therapeutic agents, cosmetics, or in other areas, such as engineering, are approached in this review. PMID:23344113

  1. Heterotrophic cultivation of microalgae for pigment production: A review.

    Science.gov (United States)

    Hu, Jianjun; Nagarajan, Dillirani; Zhang, Quanguo; Chang, Jo-Shu; Lee, Duu-Jong

    Pigments (mainly carotenoids) are important nutraceuticals known for their potent anti-oxidant activities and have been used extensively as high end health supplements. Microalgae are the most promising sources of natural carotenoids and are devoid of the toxic effects associated with synthetic derivatives. Compared to photoautotrophic cultivation, heterotrophic cultivation of microalgae in well-controlled bioreactors for pigments production has attracted much attention for commercial applications due to overcoming the difficulties associated with the supply of CO 2 and light, as well as avoiding the contamination problems and land requirements in open autotrophic culture systems. In this review, the heterotrophic metabolic potential of microalgae and their uses in pigment production are comprehensively described. Strategies to enhance pigment production under heterotrophic conditions are critically discussed and the challenges faced in heterotrophic pigment production with possible alternative solutions are presented. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Microalgae Isolation and Selection for Prospective Biodiesel Production

    Directory of Open Access Journals (Sweden)

    Peer M. Schenk

    2012-06-01

    Full Text Available Biodiesel production from microalgae is being widely developed at different scales as a potential source of renewable energy with both economic and environmental benefits. Although many microalgae species have been identified and isolated for lipid production, there is currently no consensus as to which species provide the highest productivity. Different species are expected to function best at different aquatic, geographical and climatic conditions. In addition, other value-added products are now being considered for commercial production which necessitates the selection of the most capable algae strains suitable for multiple-product algae biorefineries. Here we present and review practical issues of several simple and robust methods for microalgae isolation and selection for traits that maybe most relevant for commercial biodiesel production. A combination of conventional and modern techniques is likely to be the most efficient route from isolation to large-scale cultivation.

  3. Sustainability and economic evaluation of microalgae grown in brewery wastewater.

    Science.gov (United States)

    Mata, Teresa M; Mendes, Adélio M; Caetano, Nídia S; Martins, António A

    2014-09-01

    This article evaluates the sustainability and economic potential of microalgae grown in brewery wastewater for biodiesel and biomass production. Three sustainability and two economic indicators were considered in the evaluation within a life cycle perspective. For the production system the most efficient process units were selected. Results show that harvesting and oil separation are the main process bottlenecks. Microalgae with higher lipid content and productivity are desirable for biodiesel production, although comparable to other biofuel's feedstock concerning sustainability. However, improvements are still needed to reach the performance level of fossil diesel. Profitability reaches a limit for larger cultivation areas, being higher when extracted biomass is sold together with microalgae oil, in which case the influence of lipid content and areal productivity is smaller. The values of oil and/or biomass prices calculated to ensure that the process is economically sound are still very high compared with other fuel options, especially biodiesel. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Microalgae biorefinery symbiosis: screening, production, and process analytical technology

    DEFF Research Database (Denmark)

    Podevin, Michael Paul Ambrose

    advances in hardware and software can significantly improve microalgal bioprocess models and automation, by manipulating large, time-resolute data sets, so-called “big data,” which can be acquired through high-selectivity vibrational spectroscopy, such as mid-infrared (MIR), near-infrared (NIR), or Raman...... on the unaugmented WW. Moreover, it was demonstrated that microalgae could continue to grow in adverse environmental conditions at large-scales. The success of the in vivo fluorescence microplate assay and the complexity of these outdoor reactions demonstrate the value of pursuing real-time data of microalgae ¬in...... vibrational spectroscopies. These large, real-time data sets can now be used to create adaptive models from artificial intelligence/machine learning tools or “black-box” models, to automate large-scale, outdoor PBRs treating WW. With microalgae, now entering into a new paradigm of food, feed, pharmaceuticals...

  5. Engineering fatty acid biosynthesis in microalgae for sustainable biodiesel.

    Science.gov (United States)

    Blatti, Jillian L; Michaud, Jennifer; Burkart, Michael D

    2013-06-01

    Microalgae are a promising feedstock for biodiesel and other liquid fuels due to their fast growth rate, high lipid yields, and ability to grow in a broad range of environments. However, many microalgae achieve maximal lipid yields only under stress conditions hindering growth and providing compositions not ideal for biofuel applications. Metabolic engineering of algal fatty acid biosynthesis promises to create strains capable of economically producing fungible and sustainable biofuels. The algal fatty acid biosynthetic pathway has been deduced by homology to bacterial and plant systems, and much of our understanding is gleaned from basic studies in these systems. However, successful engineering of lipid metabolism in algae will necessitate a thorough characterization of the algal fatty acid synthase (FAS) including protein-protein interactions and regulation. This review describes recent efforts to engineer fatty acid biosynthesis toward optimizing microalgae as a biodiesel feedstock. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. Investigation of microalgae growth on electrospun nanofiber mats

    Directory of Open Access Journals (Sweden)

    Christina Großerhode

    2017-08-01

    Full Text Available Due to their large inner surface, nanofiber mats are often used in tissue engineering and examined with respect to cell adhesion, e.g., for cultivation of fibroblasts. The combination of different polymers with a large contact area, however, could also be used for growth of different plants including green microalgae. Here, the cultivation of the microalga Chlamydomonas reinhardtii on different polymer substrates was examined. We investigated growth on two nanofiber mats consisting of polyamide (PA6 and polyacrylonitrile (PAN and a polypropylene (PP microfiber mat as substrates, compared with a pure multi-well plate. It was found that the algae were able to grow on all textile mats without change in morphology, indicating that all polymers were non-toxic to the cells. Thus, these nonwovens might be suitable filters for the separation of microalgae in biotechnological processes.

  7. Proteinograma sérico de bezerros recém-nascidos alimentados com colostro de vacas com mastite

    Directory of Open Access Journals (Sweden)

    Guilherme Gonçalves Fabretti Santos

    2013-06-01

    Full Text Available O objetivo do presente estudo foi o de avaliar o proteinograma sérico de bezerros alimentados com colostro oriundo de vacas sadias (n = 10, com mastite assintomática (n = 10 e mastite clínica (n =10 . As vacas foram alocadas em seus respectivos grupos de acordo com o exame macroscópico da secreção colostral, contagem de células somáticas, CMT e isolamento microbiano. As amostras de sangue dos conceptos foram colhidas logo após o nascimento, 24 e 48 horas após a ingestão do colostro dos quartos infectados e dos sadios. Foi avaliada a concentração de proteína total pelo método do biureto e as concentrações de imunoglobulina A (IgA, imunoglobulina G (IgG, transferrina, albumina e haptoglobina por meio da eletrofoerese em gel de poliacrilamida contendo dodecil sulfato de sódio (SDS-PAGE. Não foram observadas diferenças entre os grupos nas concentrações de albumina, proteína total e IgA. Os bezerros alimentados com colostro de vacas com mastite assintomática e clínica apresentaram teores de haptoglobina superiores aos animais sadios. As concentrações de IgG e transferrina foram significativamente inferiores nos bezerros tratados com colostro de vacas com mastite clínica. Concluiu-se que a ingestão de colostro de quartos sadios e infectados de vacas que pariram com mastite (GII e GIII não resulta em falha de transferência da imunidade passiva.

  8. Lipids rich in ω-3 polyunsaturated fatty acids from microalgae.

    Science.gov (United States)

    Santos-Sánchez, N F; Valadez-Blanco, R; Hernández-Carlos, B; Torres-Ariño, A; Guadarrama-Mendoza, P C; Salas-Coronado, R

    2016-10-01

    Despite microalgae recently receiving enormous attention as a potential source of biodiesel, their use is still not feasible as an alternative to fossil fuels. Recently, interest in microalgae has focused on the production of bioactive compounds such as polyunsaturated fatty acids (PUFA), which provide microalgae a high added value. Several considerations need to be assessed for optimizing PUFA production from microalgae. Firstly, a microalgae species that produces high PUFA concentrations should be selected, such as Nannochloropsis gaditana, Isochrysis galbana, Phaeodactylum tricornutum, and Crypthecodinium cohnii, with marine species gaining more attention than do freshwater species. Closed cultivation processes, e.g., photobioreactors, are the most appropriate since temperature, pH, and nutrients can be controlled. An airlift column with LEDs or optical fibers to distribute photons into the culture media can be used at small scale to produce inoculum, while tubular and flat panels are used at commercial scale. Depending on the microalgae, a temperature range from 15 to 28 °C and a pH from 7 to 8 can be employed. Relevant conditions for PUFA production are medium light irradiances (50-300 μmol photons m(-2) s(-1)), air enriched with (0-1 % (v/v) CO2, as well as nitrogen and phosphorous limitation. For research purposes, the most appropriate medium for PUFA production is Bold's Basal, whereas mixotrophic cultivation using sucrose or glucose as the carbon source has been reported for industrial processes. For cell harvesting, the use of tangential flow membrane filtration or disk stack centrifugation is advisable at commercial scale. Current researches on PUFA extraction have focused on the use of organic solvents assisted with ultrasound or microwaves, supercritical fluids, and electroporation or are enzyme assisted. Commercial-scale extraction involves mainly physical methods such as bead mills and expeller presses. All these factors should be taken into

  9. Biogas Production From Cassava Starch Effluent Using Microalgae As Biostabilisator

    Directory of Open Access Journals (Sweden)

    B. Budiyono

    2011-07-01

    Full Text Available The rapid growing of Indonesian population is emerging several critical national issues i.e. energy, food, environmental, water, transportation, as well as law and human right. As an agricultural country, Indonesia has abundant of biomass wastes such as agricultural wastes include the cassava starch wastes. The problem is that the effluent from cassava starch factories is released directly into the river before properly treatment. It has been a great source of pollution and has caused environmental problems to the nearby rural population. The possible alternative to solve the problem is by converting waste to energy biogas in the biodigester. The main problem of the biogas production of cassava starch effluent is acid forming-bacteria quickly produced acid resulting significantly in declining pH below the neutral pH and diminishing growth of methane bacteria. Hence, the only one of the method to cover this problem is by adding microalgae as biostabilisator of pH. Microalgae can also be used as purifier agent to absorb CO2.The general objective of this research project was to develop an integrated process of biogas production and purification from cassava starch effluent by using biostabilisator agent microalgae. This study has been focused on the used of urea, ruminant, yeast, microalgae, the treatment of gelled and ungelled feed for biogas production, pH control during biogas production using buffer Na2CO3, and feeding management in the semi-continuous process of biogas production. The result can be concluded as follows: i The biogas production increased after cassava starch effluent and yeast was added, ii Biogas production with microalgae and cassava starch effluent, yeast, ruminant bacteria, and urea were 726.43 ml/g total solid, iii Biogas production without  microalgae was 189 ml/g total solid.

  10. Non-photoautotrophic cultivation of microalgae: an overview

    Directory of Open Access Journals (Sweden)

    Elisangela Andrade Angelo

    2014-12-01

    Full Text Available Microalgae are a heterogeneous group of microorganisms that produces biomass from which can be extracted various products such as proteins, carbohydrates, pigments and oils with profile containing saturated fatty acids, polyunsaturated and monounsaturated. These microorganisms have different forms of energetic metabolism, especially the photoautotrophic, heterotrophic, and mixotrophic photoautotrophic. Understanding these metabolic forms allows to apply microalgae strategies of cultivation aiming to increase algal biomass production, and its co-products in large scales. Traditionally, the microalgae cultivation is done by exploiting their photoautotrophic metabolism. However, studies have point out some advantages in the production of biomass of these microorganisms by using other metabolic pathways. Thus, this review aims to present an overview of the forms of non-photoautotrophic microalgae metabolism and considerations on the different systems of biomass production of these microorganisms. In the heterotrophic metabolism, sources of carbon that have stood out the most for microalgae are: glucose, glycerol and acetic acid. Nevertheless, there are several studies that present alternative sources of culture medium, such as agro-industrial and sanitary waste. The mixotrophic can be defined as the metabolism when photosynthesis and oxidation of external organic carbon take place at the same time. In the photoherotrophic metabolism is the light energy source and the organic compound is a carbon source. The non-photoautotrophic cultivation systems are high potential, mainly for increasing production with better productivity and scaling up. However, it should be noted that information about these microalgae cultivation systems on a large scale for a competitive production is scarce.

  11. Batch anaerobic co-digestion of waste activated sludge and microalgae (Chlorella sorokiniana) at mesophilic temperature.

    Science.gov (United States)

    Beltrán, Carolina; Jeison, David; Fermoso, Fernando G; Borja, Rafael

    2016-08-23

    The microalgae Chlorella sorokiniana are used as co-substrate for waste activated sludge (WAS) anaerobic digestion. The specific objective of this research was to evaluate the feasibility of improving methane production from anaerobic digestion of WAS in co-digestion with this microalga, based on an optimized mixture percentage. Thus, the anaerobic co-digestion of both substrates aims to overcome the drawbacks of the anaerobic digestion of single WAS, simultaneously improving its management. Different co-digestion mixtures (0% WAS-100% microalgae; 25% WAS-75% microalgae; 50% WAS-50% microalgae; 75% WAS-25% microalgae; 100% WAS-0% microalgae) were studied. The highest methane yield (442 mL CH4/g VS) was obtained for the mixture with 75% WAS and 25% microalgae. This value was 22% and 39% higher than that obtained in the anaerobic digestion of the sole substrates WAS and microalgae, respectively, as well as 16% and 25% higher than those obtained for the co-digestion mixtures with 25% WAS and 75% microalgae and 50% WAS and 50% microalgae, respectively. The kinetic constant of the process increased 42%, 42% and 12%, respectively, for the mixtures with 25%, 50% and 75% of WAS compared to the substrate without WAS. Anaerobic digestion of WAS, together with C. sorokiniana, has been clearly improved by ensuring its viability, suitability and efficiency.

  12. Effects of bacterial communities on biofuel-producing microalgae: stimulation, inhibition and harvesting.

    Science.gov (United States)

    Wang, Hui; Hill, Russell T; Zheng, Tianling; Hu, Xiaoke; Wang, Bin

    2016-01-01

    Despite the great interest in microalgae as a potential source of biofuel to substitute for fossil fuels, little information is available on the effects of bacterial symbionts in mass algal cultivation systems. The bacterial communities associated with microalgae are a crucial factor in the process of microalgal biomass and lipid production and may stimulate or inhibit growth of biofuel-producing microalgae. In addition, we discuss here the potential use of bacteria to harvest biofuel-producing microalgae. We propose that aggregation of microalgae by bacteria to achieve >90% reductions in volume followed by centrifugation could be an economic approach for harvesting of biofuel-producing microalgae. Our aims in this review are to promote understanding of the effects of bacterial communities on microalgae and draw attention to the importance of this topic in the microalgal biofuel field.

  13. Mitigación de la toxicidad anaerobia de lixiviados mediante mezclas con agua residual doméstica

    Directory of Open Access Journals (Sweden)

    Patricia Torres

    2010-01-01

    Full Text Available Los lixiviados contienen compuestos originalmente presentes en los residuos depositados en el relleno así como los formados en los procesos de degradación; cuando presentan altos contenidos de material orgánico y alta relación DBO5/DQO, el tratamiento biológico tiene gran potencial de aplicación; sin embargo, los altos niveles de nitrógeno y otros compuestos pueden ser inhibitorios o tóxicos para el proceso biológico. La evaluación de la toxicidad anaerobia permite determinar la magnitud y tipo de inhibición causada sobre los microorganismos encargados de la transformación final a metano y se determina comparando la Actividad Metanogénica Específica (AME del lodo control alimentado únicamente con sustrato, con la AME del lodo alimentado con el mismo sustrato más el compuesto tóxico. Dado el creciente interés en el cotratamiento de lixiviados con aguas residuales domésticas (ARD, se evaluó en escala de laboratorio la toxicidad anaerobia de lixiviados puros y mezclados con ARD para establecer el potencial efecto tóxico del lixiviado sobre la digestión anaerobia. En los ensayos usando lixiviado puro, se presentó una elevada reducción de la AME, identificándose dos tipos de inhibición: metabólica y fisiológica. En los ensayos usando mezclas de lixiviado y ARD (5 y 10%, el porcentaje de inhibición se redujo sustancialmente, alcanzándose condiciones de sustratos no tóxicos. Los resultados sugieren la potencialidad de aplicación del cotratamiento con ARD como una estrategia adecuada de manejo de lixiviados.

  14. USE OF BACTERIA AND MICROALGAE IN SYNTHESIS OF NANOPARTICLES

    Directory of Open Access Journals (Sweden)

    Inga Zinicovscaia

    2012-12-01

    Full Text Available A critical need in the field of nanotechnology is the development of a reliable and eco-friendly process for synthesis of metallic nanoparticles. A number of different organisms, including bacteria, microalgae, yeast and fungi, have shown their ability to produce metal nanoparticles. But they have some drawbacks in providing better control over size distribution, shape and crystallinity. This review article presents an overview of microorganisms (bacteria and microalga capable of producing silver and gold nanoparticles. This article is an extended abstract of a communication presented at the Conference Ecological Chemistry 2012

  15. Terpenes as Green Solvents for Extraction of Oil from Microalgae

    Directory of Open Access Journals (Sweden)

    Celine Dejoye Tanzi

    2012-07-01

    Full Text Available Herein is described a green and original alternative procedure for the extraction of oil from microalgae. Extractions were carried out using terpenes obtained from renewable feedstocks as alternative solvents instead of hazardous petroleum solvents such as n-hexane. The described method is achieved in two steps using Soxhlet extraction followed by the elimination of the solvent from the medium using Clevenger distillation in the second step. Oils extracted from microalgae were compared in terms of qualitative and quantitative determination. No significant difference was obtained between each extract, allowing us to conclude that the proposed method is green, clean and efficient.

  16. Terpenes as green solvents for extraction of oil from microalgae.

    Science.gov (United States)

    Dejoye Tanzi, Celine; Abert Vian, Maryline; Ginies, Christian; Elmaataoui, Mohamed; Chemat, Farid

    2012-07-09

    Herein is described a green and original alternative procedure for the extraction of oil from microalgae. Extractions were carried out using terpenes obtained from renewable feedstocks as alternative solvents instead of hazardous petroleum solvents such as n-hexane. The described method is achieved in two steps using Soxhlet extraction followed by the elimination of the solvent from the medium using Clevenger distillation in the second step. Oils extracted from microalgae were compared in terms of qualitative and quantitative determination. No significant difference was obtained between each extract, allowing us to conclude that the proposed method is green, clean and efficient.

  17. Potency of Microalgae as Biodiesel Source in Indonesia

    Directory of Open Access Journals (Sweden)

    H Hadiyanto

    2012-04-01

    Full Text Available Within 20 years, Indonesia should find another energy alternative to substitutecurrent fossil oil. Current use of renewable energy is only 5% and need to be improved up to 17%of our energy mix program. Even though, most of the area in Indonesia is covered by sea, howeverthe utilization of microalgae as biofuel production is still limited. The biodiesel from currentsources (Jatropha, palm oil, and sorghum is still not able to cover all the needs if the fossil oilcannot be explored anymore. In this paper, the potency of microalgae in Indonesia was analysed asthe new potential of energy (biodiesel sources.

  18. Biofuel production from microalgae as feedstock: current status and potential.

    Science.gov (United States)

    Han, Song-Fang; Jin, Wen-Biao; Tu, Ren-Jie; Wu, Wei-Min

    2015-06-01

    Algal biofuel has become an attractive alternative of petroleum-based fuels in the past decade. Microalgae have been proposed as a feedstock to produce biodiesel, since they are capable of mitigating CO2 emission and accumulating lipids with high productivity. This article is an overview of the updated status of biofuels, especially biodiesel production from microalgae including fundamental research, culture selection and engineering process development; it summarizes research on mathematical and life cycle modeling on algae growth and biomass production; and it updates global efforts of research and development and commercialization attempts. The major challenges are also discussed.

  19. A quick colorimetric method for total lipid quantification in microalgae.

    Science.gov (United States)

    Byreddy, Avinesh R; Gupta, Adarsha; Barrow, Colin J; Puri, Munish

    2016-06-01

    Discovering microalgae with high lipid productivity are among the key milestones for achieving sustainable biodiesel production. Current methods of lipid quantification are time intensive and costly. A rapid colorimetric method based on sulfo-phospho-vanillin (SPV) reaction was developed for the quantification of microbial lipids to facilitate screening for lipid producing microalgae. This method was successfully tested on marine thraustochytrid strains and vegetable oils. The colorimetric method results correlated well with gravimetric method estimates. The new method was less time consuming than gravimetric analysis and is quantitative for lipid determination, even in the presence of carbohydrates, proteins and glycerol. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Microalgae: An alternative as sustainable source of biofuels?

    International Nuclear Information System (INIS)

    Amaro, Helena M.; Macedo, Ângela C.; Malcata, F. Xavier

    2012-01-01

    In recent decades, the world has been confronted with an energy crisis associated with irreversible depletion of traditional sources of fossil fuels, coupled with atmospheric accumulation of greenhouse gases that cause global warming. The urgent need to replace traditional fuels led to emergence of biodiesel and biohydrogen as interesting alternatives, both of which can be obtained via microalga-mediated routes. Microalgae are ubiquitous eukaryotic microorganisms, characterized by a remarkable metabolic plasticity. Their oil productivities are much higher than those of higher terrestrial plants, and they do not require high quality agricultural land. Microalgae may indeed be cultivated in brackish and wastewaters that provide suitable nutrients (e.g. NH 4 + ,NO 3 − andPO 4 3− ), at the expense of only sunlight and atmospheric CO 2 . On the other hand, metabolic engineering permits release of molecular hydrogen also via photosynthetic routes, which will easily be converted to electricity in fuel cells or mechanical power in explosion engines, with only water vapor as exhaust product in both cases. However, large-scale implementation of microalga-based systems to manufacture biodiesel and biohydrogen has been economically constrained by their still poor volumetric efficiencies, which imply excessively high costs when compared with current petrofuel prices. Technological improvements are accordingly critical, both on the biocatalyst and the bioreactor levels. The current bottlenecks that have apparently precluded full industrial exploitation of microalgae cells are critically discussed here, viz. those derived from the scarce knowledge on the mechanisms that control regulation of gene expression, the reduced number of species subjected to successful genetic transformation, the relatively low cell density attainable, the poor efficiency in harvesting, and the difficulties in light capture and use. Therefore, this paper provides an overview of the feasibility of

  1. Percepción materna de leche insuficiente y lactogénesis II: Factores de riesgo en el postparto temprano y relación con el abandono prematuro de la lactancia.

    OpenAIRE

    Oliva Pérez, José

    2017-01-01

    Antecedentes: La lactancia materna es la alimentación idónea para cualquier neonato, recomendándose de manera exclusiva hasta los 6 meses de edad, y hasta los dos años o más junto con alimentación complementaria. Este tipo de alimentación aporta conocidos beneficios dosis dependiente al lactante y también a la madre. A pesar de las recomendaciones internacionales, a nivel mundial sólo el 37% de los bebés menores de 6 meses son alimentados con lactancia materna exclusiva, y en España el 28...

  2. Producción de moina sp alimentada con chlorella spp. cultivada con riles orgánicos de la industria pesquera cubana.

    OpenAIRE

    Romero, Teresita de J.; Manso, B.M.; López, R.; Martínez, F.C.; Moreno, M.

    2010-01-01

    El incremento sustancial de la acuicultura cubana y la carencia de algunos fertilizantes usados para fines de cultivo fitoplantónico, que finalmente pasan a nutrir especies zooplanctónicas como el cladócero Moina, ha dado pauta para realizar el presente estudio, referido al cultivo de dicha especie con la microalga Chlorella spp. desarrollada previamente con riles orgánicos de la industria pesquera. Se realizaron dos tandas experimentales: 1) en acuarios de 50 L de capacidad efect...

  3. IDENTIFICACIÓN DE MICROALGAS OLEAGINOSAS EN EL ÁREA DE CONCESIÓN PARA CONSERVACIÓN, CUENCA ALTA DEL RÍO ITAYA. LORETO-PERÚ

    Directory of Open Access Journals (Sweden)

    Marianela Cobos Ruiz

    2012-12-01

    Full Text Available Las microalgas oleaginosas constituyen una nueva alternativa para la producción de biodiesel, por su alta eficiencia fotobiosintética de triglicéridos y presentan productividades mayores de 10 a 100 veces que los cultivos convencionales. Además que actúan como sumideros de CO2 y pueden usar aguas servidas para producir biodiesel. Sin embargo, los estudios sobre identificación de este tipo de microalgas en la amazonía son escasos. El objetivo del presente trabajo de investigación fue identificar especies de microalgas oleaginosas con potencial aplicación para la producción de biodiesel que se encuentran en ambientes acuáticos del Área de Concesión para Conservación de la Universidad Científica del Perú (UCP. La colecta de las muestras se realizó del 27/06/12 al 03/07/12 entre las 12 y 15 h utilizando red planctónica tipo cono y como preservante formol al 3%. La identificación microscópica se realizó en el Laboratorio de Ciencias Básicas de la UCP. La densidad de las microalgas fue realizada en base a su conteo en cámaras de Neubauer  y Sedgwick-Rafter. Los resultados muestran la presencia de 20 especies de microalgas, de las cuales cinco son microalgas oleaginosas. Correspondiente a las del género Chlorella quienes presentaron la mayor densidad promedio (6x104 células/ml en las tres cochas evaluadas.

  4. Effects of short-term sediment nutrient enrichment and grazer (Neritina reclivata removal on sediment microalgae in a shallow eutrophic estuary (Alabama, USA

    Directory of Open Access Journals (Sweden)

    Just Cebrian

    2012-12-01

    sedimentary areas studied. Our findings contrast with the results of past work in sediments with well-lit and nutrient poor conditions, or sediments with high densities of other snail grazers. In conjunction this and other investigations indicate that the response of sediment microalgae to nutrient enrichment and modified grazer abundance depends to a large extent on the initial levels of nutrient availability and grazing before the system is altered.El caracol Neritina reclivata está presente en los sistemas tropicales y subtropicales del Golfo de México, sin embargo, su impacto en los sedimentos de microalgas ha sido poco estudiado. Muchos de los sistemas costeros de todo el mundo están siendo eutrofizados debido a actividades humanas, y al parecer van a seguir siendo eutrofizados en mayor grado en el futuro. La exploración de los efectos individuales y combinados de un mayor enriquecimiento de nutrientes y la herviboría por este caracol en microalgas de sedimentos en estos sistemas eutróficos es una cuestión importante para la comprensión y el manejo de estos sistemas. Aquí se examinan los efectos a corto plazo del enriquecimiento de nutrientes y herviboría del caracol de olivo sobre la biomasa y composición de microalgas de sedimentos en un estuario eutrófico superficial (Weeks Bay. Alabama, USA del norte del Golfo de México. Para esto se llevaron a cabo una serie de experimentos factoriales añadiendo o no nutrientes y removiendo o no el caracol, para un total de cuatro tratamientos en cada experimento: ambiente con herviboría sin nutrimentos añadidos, ambiente con herviboría y nutrimentos añadidos, ambiente sin herviboría sin nutrimentos añadidos, y ambiente sin herviboría con nutrimentos añadidos. No se encontró ningún impacto significativo por la adición de nutrimentos en ninguno de los ocho experimentos a corto plazo (i.e. cuatro días. Los impactos debidos al caracol fueron menores, sólo se encontró un decrecimiento en la biomasa por

  5. Consumo e digestibilidade aparente dos nutrientes em ovinos alimentados com dietas contendo diferentes quantidades de farelo de linhaça

    OpenAIRE

    Danieli Perez Fernandes; Paulo de Figueiredo Vieira; Carlos Henrique Silveira Rabelo; Flávio Henrique Silveira Rabelo; Flávio Moreno Salvador; Adauton Vilela de Rezende; Ricardo Andrade Reis

    2013-01-01

    Objetivou-se com este trabalho avaliar o consumo e digestibilidade aparente dos nutrientes emovinos alimentados com dietas contendo diferentes quantidades de farelo de linhaça. Avaliaramsequatro dietas: silagem de milho exclusiva - SM; SM + concentrado; SM + concentrado + 5% defarelo de linhaça - FL; SM + concentrado +10% de FL. O consumo de matéria seca (MS) aumentounas dietas contendo concentrado quando comparado à dieta com silagem de milho exclusiva(P

  6. Laboratory sulfurisation of the marine microalga Nannochloropsis salina

    NARCIS (Netherlands)

    Sinninghe Damsté, J.S.; Gelin, F.; Kok, M.D.; Leeuw, J.W. de

    1998-01-01

    To understand more fully the mode of preservation of organic matter in marine sediments, laboratory sulfurisation of intact cells of the cultured microalga Nannochloropsis salina was performed using inorganic polysulfides in seawater at 50°C. Solvent extractable and non-extractable materials were

  7. Adhesion of Chlamydomonas microalgae to surfaces is switchable by light

    Science.gov (United States)

    Kreis, Christian Titus; Le Blay, Marine; Linne, Christine; Makowski, Marcin Michal; Bäumchen, Oliver

    2018-01-01

    Microalgae are photoactive microbes that live in liquid-infused environments, such as soil, temporary pools and rocks, where they encounter and colonize a plethora of surfaces. Their photoactivity manifests itself in a variety of processes, including light-directed motility (phototaxis), the growth of microalgal populations, and their photosynthetic machinery. Although microbial responses to light have been widely recognized, any influence of light on cell-surface interactions remains elusive. Here, we reveal that the unspecific adhesion of microalgae to surfaces can be reversibly switched on and off by light. Using a micropipette force spectroscopy technique, we measured in vivo single-cell adhesion forces and show that the microalga's flagella provide light-switchable adhesive contacts with the surface. This light-induced adhesion to surfaces is an active and completely reversible process that occurs on a timescale of seconds. Our results suggest that light-switchable adhesiveness is a natural functionality of microalgae to regulate the transition between the planktonic and the surface-associated state, which yields an adhesive adaptation to optimize the photosynthetic efficiency in conjunction with phototaxis.

  8. A techno-economic analysis of biodiesel production from microalgae

    NARCIS (Netherlands)

    Olivieri, G.; Guida, T.; Salatino, P.; Marzocchella, A.

    2013-01-01

    The preliminary assessment of a cost-effective flow-sheet for the production of biodiesel from microalgae lipid fraction was carried out. The study was based on approximated cost-estimation methods integrated with the simulation software Aspen Plus (R). Several scenarios were investigated to compare

  9. Visual Simulation of Microalgae Growth in Bioregenerative Life Support System

    Science.gov (United States)

    Zhao, Ming

    Bioregenerative life support system is one of the key technologies for future human deep space exploration and long-term space missions. BLSS use biological system as its core unit in combination with other physical and chemical equipments, under the proper control and manipulation by crew to complete a specific task to support life. Food production, waste treatment, oxygen and water regeneration are all conducted by higher plants or microalgae in BLSS, which is the most import characteristic different from other kinds of life support systems. Microalgae is light autotrophic micro-organisms, light undoubtedly is the most import factor which limits its growth and reproduction. Increasing or decreasing the light intensity changes the growth rate of microalgae, and then regulates the concentration of oxygen and carbon dioxide in the system. In this paper, based on the mathematical model of microalgae which grew under the different light intensity, three-dimensional visualization model was built and realized through using 3ds max, Virtools and some other three dimensional software, in order to display its change and impacting on oxygen and carbon dioxide intuitively. We changed its model structure and parameters, such as establishing closed-loop control system, light intensity, temperature and Nutrient fluid’s velocity and so on, carried out computer virtual simulation, and observed dynamic change of system with the aim of providing visualization support for system research.

  10. Combustion of Microalgae Oil and Ethanol Blended with Diesel Fuel

    Directory of Open Access Journals (Sweden)

    Saddam H. Al-lwayzy

    2015-12-01

    Full Text Available Using renewable oxygenated fuels such as ethanol is a proposed method to reduce diesel engine emission. Ethanol has lower density, viscosity, cetane number and calorific value than petroleum diesel (PD. Microalgae oil is renewable, environmentally friendly and has the potential to replace PD. In this paper, microalgae oil (10% and ethanol (10% have been mixed and added to (80% diesel fuel as a renewable source of oxygenated fuel. The mixture of microalgae oil, ethanol and petroleum diesel (MOE20% has been found to be homogenous and stable without using surfactant. The presence of microalgae oil improved the ethanol fuel demerits such as low density and viscosity. The transesterification process was not required for oil viscosity reduction due to the presence of ethanol. The MOE20% fuel has been tested in a variable compression ratio diesel engine at different speed. The engine test results with MOE20% showed a very comparable engine performance of in-cylinder pressure, brake power, torque and brake specific fuel consumption (BSFC to that of PD. The NOx emission and HC have been improved while CO and CO2 were found to be lower than those from PD at low engine speed.

  11. Technical Note: Development of a Photobioreactor for Microalgae ...

    African Journals Online (AJOL)

    In view of the technical and biological limitations of open pond systems, a study was conducted to develop a cost-effective experimental photobioreactor that would permit efficient cultivation of microalgae for biodiesel production. The photobioreactor was developed using low cost materi- als, cylindrical translucent tubes ...

  12. Evaluation of the Antioxidant Activity of Cell Extracts from Microalgae

    Directory of Open Access Journals (Sweden)

    F. Xavier Malcata

    2013-04-01

    Full Text Available A growing market for novel antioxidants obtained from non-expensive sources justifies educated screening of microalgae for their potential antioxidant features. Characterization of the antioxidant profile of 18 species of cyanobacteria (prokaryotic microalgae and 23 species of (eukaryotic microalgae is accordingly reported in this paper. The total antioxidant capacity, accounted for by both water- and lipid-soluble antioxidants, was evaluated by the (radical cation ABTS method. For complementary characterization of cell extracts, a deoxyribose assay was carried out, as well as a bacteriophage P22/Salmonella-mediated approach. The microalga Scenedesmus obliquus strain M2-1 exhibited the highest (p > 0.05 total antioxidant capacity (149 ± 47 AAU of intracellular extracts. Its scavenger activity correlated well with its protective effects against DNA oxidative damage induced by copper(II-ascorbic acid; and against decay in bacteriophage infection capacity induced by H2O2. Finally, performance of an Ames test revealed no mutagenic effects of the said extract.

  13. Lichen microalgae are sensitive to environmental concentrations of atrazine.

    Science.gov (United States)

    Traba, Helena Moreno; Domínguez-Morueco, Noelia; Barreno, Eva; Catalá, Myriam

    2017-04-03

    The identification of new organisms for environmental toxicology bioassays is currently a priority, since these tools are strongly limited by the ecological relevance of taxa used to study global change. Lichens are sensitive bioindicators of air quality and their microalgae are an untapped source for new low-cost miniaturized bioassays with ecological importance. In order to increase the availability of a wider range of taxa for bioassays, the sensitivity of two symbiotic lichen microalgae, Asterochloris erici and Trebouxia sp. TR9, to atrazine was evaluated. To achieve this goal, axenic cultures of these phycobionts in suspension were exposed to a range of environmental concentrations of the herbicide atrazine, a common water pollutant. Optical density and chlorophyll autofluorescence were used as endpoints of ecotoxicity and ecophysiology on cell suspensions. Results show that lichen microalgae show high sensitivity to very low doses of atrazine, being higher in Asterochloris erici than in Trebouxia sp. TR9. We conclude that environmental concentrations of atrazine could modify population dynamics probably through a shift in reproduction strategies of these organisms. This seminal work is a breakthrough in the use of lichen microalgae in the assessment of micropollution effects on biodiversity.

  14. Evaluation of microalgae production coupled with wastewater treatment

    DEFF Research Database (Denmark)

    De Francisci, Davide; Su, Yixi; Iital, Arvo

    2018-01-01

    In the present study the feasibility of microalgae production coupled with wastewater treatment was assessed. Continuous cultivation of Chlorella sorokiniana with wastewater was tested in lab-scale flat panel photobioreactors. Biomass productivity was determined for four dilution rates (4.32 d-1, 3...

  15. Hazard and risk of herbicides for marine microalgae

    NARCIS (Netherlands)

    Sjollema, S.B.; Martínez-García, G.; van der Geest, H.G.; Kraak, M.H.S.; Booij, P.; Vethaak, A.D.; Admiraal, W.

    2014-01-01

    Due to their specific effect on photosynthesis, herbicides pose a potential threat to coastal and estuarine microalgae. However, comprehensive understanding of the hazard and risk of these contaminants is currently lacking. Therefore the aim of the present study was to investigate the toxic effects

  16. Hazard and risk of herbicides for marine microalgae

    International Nuclear Information System (INIS)

    Sjollema, Sascha B.; MartínezGarcía, Gema; Geest, Harm G. van der; Kraak, Michiel H.S.; Booij, Petra; Vethaak, A. Dick; Admiraal, Wim

    2014-01-01

    Due to their specific effect on photosynthesis, herbicides pose a potential threat to coastal and estuarine microalgae. However, comprehensive understanding of the hazard and risk of these contaminants is currently lacking. Therefore the aim of the present study was to investigate the toxic effects of four ubiquitous herbicides (atrazine, diuron, Irgarol ® 1051 and isoproturon) and herbicide mixtures on marine microalgae. Using a Pulse Amplitude Modulation (PAM) fluorometry based bioassay we demonstrated a clear species and herbicide specific toxicity and showed that the current environmental legislation does not protect algae sufficiently against diuron and isoproturon. Although a low actual risk of herbicides in the field was demonstrated, monitoring data revealed that concentrations occasionally reach potential effect levels. Hence it cannot be excluded that herbicides contribute to observed changes in phytoplankton species composition in coastal waters, but this is likely to occur only occasionally. - Highlights: • The hazard of herbicides for microalgae is compound and species specific. • In general a low risk although occasional potential effect levels are reached. • Current legislation does not protect marine microalgae sufficiently. - The hazard of herbicides in the coastal waters is compound and species specific and although the general risk in the field is low, occasionally potential effect levels are reached

  17. Rapid biodiesel production using wet microalgae via microwave irradiation

    International Nuclear Information System (INIS)

    Wahidin, Suzana; Idris, Ani; Shaleh, Sitti Raehanah Muhamad

    2014-01-01

    Highlights: • Lipid was directly extracted from wet microalgae using microwave irradiation. • The microwave irradiation and water bath-assisted solvent extraction are applied. • Cell walls are significantly disrupted under microwave irradiation. • Highly disrupted cell walls led to higher biodiesel yield in microwave irradiation. • Microwave irradiation is a promising direct technique with high biodiesel yields. - Abstract: The major challenges for industrial commercialized biodiesel production from microalgae are the high cost of downstream processing such as dewatering and drying, utilization of large volumes of solvent and laborious extraction processes. In order to address these issues the microwave irradiation method was used to produce biodiesel directly from wet microalgae biomass. This alternative method of biodiesel production from wet microalgae biomass is compared with the conventional water bath-assisted solvent extraction. The microwave irradiation extracted more lipids and high biodiesel conversion was obtained compared to the water bath-assisted extraction method due to the high cell disruption achieved and rapid transesterification. The total content of lipid extracted from microwave irradiation and water bath-assisted extraction were 38.31% and 23.01% respectively. The biodiesel produced using microwave irradiation was higher (86.41%) compared to the conventional method. Thus microwave irradiation is an attractive and promising technology to be used in the extraction and transesterification process for efficient biodiesel production

  18. Potential of sponges and microalgae for marine biotechnology

    NARCIS (Netherlands)

    Wijffels, R.H.

    2008-01-01

    Marine organisms can be used to produce several novel products that have applications in new medical technologies, in food and feed ingredients and as biofuels. In this paper two examples are described: the development of marine drugs from sponges and the use of microalgae to produce bulk chemicals

  19. Isolation of microalgae species from arid environments and ...

    African Journals Online (AJOL)

    sunny t

    2015-05-06

    May 6, 2015 ... Twenty-five (25) strains of microalgae were isolated and screened for growth, lipid accumulation and biodiesel production from .... tubes arranged in parallel with maximum light intensity of 5000 lux. The photoperiod was ... pumping times was 4, and injection port dwell time was 0.3 s. There was no terminal ...

  20. Cultivation of freshwater microalgae in biodiesel wash water.

    Science.gov (United States)

    Sassi, Patrícia Giulianna Petraglia; Calixto, Clediana Dantas; da Silva Santana, Jordana Kaline; Sassi, Roberto; Costa Sassi, Cristiane Francisca; Abrahão, Raphael

    2017-08-01

    Biodiesel wash water is a contaminating industrial effluent that must be treated prior to disposal. The use of this effluent as a low-cost alternative cultivation medium for microalgae could represent a viable supplementary treatment. We cultivated 11 microalgae species with potential use for biodiesel production to assess their growth capacities in biodiesel industrial washing waters. Only Monoraphidium contortum, Ankistrodesmus sp., Chlorococcum sp., and one unidentified Chlorophyceae species grew effectively in that effluent. M. contortum showed the highest growth capacity and had the second highest fatty acid content (267.9 mg g -1 of DW), predominantly producing palmitic (20.9%), 7,10,13-hexadecatrienoic (14%), oleic (16.2%), linoleic (10.5%), and linolenic acids (23.2%). In the second phase of the experiment, the microalgae were cultivated in biodiesel wash water at 75% of its initial concentration as well as in WC (control) medium. After 21 days of cultivation, 25.8 and 7.2% of the effluent nitrate and phosphate were removed, respectively, and the chemical oxygen demand was diminished by 31.2%. These results suggest the possibility of cultivating biodiesel producing microalgae in industrial wash water effluents.

  1. Micro-algae: the Rise of Next Generation Biofuels

    CSIR Research Space (South Africa)

    Moodley, G

    2015-03-01

    Full Text Available stream_source_info Moodley_2015.pdf.txt stream_content_type text/plain stream_size 1163 Content-Encoding UTF-8 stream_name Moodley_2015.pdf.txt Content-Type text/plain; charset=UTF-8 Chapter 5 Micro-algae: the Rise...

  2. Extremophilic micro-algae and their potential contribution in biotechnology.

    Science.gov (United States)

    Varshney, Prachi; Mikulic, Paulina; Vonshak, Avigad; Beardall, John; Wangikar, Pramod P

    2015-05-01

    Micro-algae have potential as sustainable sources of energy and products and alternative mode of agriculture. However, their mass cultivation is challenging due to low survival under harsh outdoor conditions and competition from other, undesired, species. Extremophilic micro-algae have a role to play by virtue of their ability to grow under acidic or alkaline pH, high temperature, light, CO2 level and metal concentration. In this review, we provide several examples of potential biotechnological applications of extremophilic micro-algae and the ranges of tolerated extremes. We also discuss the adaptive mechanisms of tolerance to these extremes. Analysis of phylogenetic relationship of the reported extremophiles suggests certain groups of the Kingdom Protista to be more tolerant to extremophilic conditions than other taxa. While extremophilic microalgae are beginning to be explored, much needs to be done in terms of the physiology, molecular biology, metabolic engineering and outdoor cultivation trials before their true potential is realized. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Biomass of Microalgae as a Source of Renewable Energy

    Directory of Open Access Journals (Sweden)

    Głowacka Natalia

    2017-05-01

    Full Text Available Algae represent a potential source of energy via anaerobic digestion. The aim of the study was to obtain the possible potential of green microalgae, which could replace the commonly used corn silage for the production of biogas in the future. The intensive construction of new biogas plants stations across Europe and the lack of arable land suitable for the cultivation of biomass for energy purposes are the fundamental reasons behind looking for the alternative raw materials for energy production as a substitute for commonly used input materials. When comparing green microalgae with conventional crops the high productivity potential (high oil content as well as the possibility of their production during the whole year can be noticed. It is necessary to find the effective way to produce biomass from green microalgae, proper for energy conversion, while ensuring the economic and environmental aspects. The interim research results mentioned in this article indicate that microalgae present appropriate alternative material for the process of anaerobic digestion.

  4. Potentials of Microalgae Biodiesel Production in Nigeria | Ogbonna ...

    African Journals Online (AJOL)

    There is high potential for largescale production of biodiesel from microalgae in Nigeria. Establishment of biodiesel production industries in Nigeria will have positive effects on socio-economic development of the country. It has been estimated that Nigeria currently needs about 27 thousand barrels of biodiesel per day to be ...

  5. Isolation of microalgae species from arid environments and ...

    African Journals Online (AJOL)

    Twenty-five (25) strains of microalgae were isolated and screened for growth, lipid accumulation and biodiesel production from arid environments of North East Nigeria. Isolates that produced biomass concentration (≥ 1.50 g L-1 cell dry weight), accumulated high concentrations of lipids (≥ 18% of the cell biomass) and ...

  6. 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

  7. MICROALGAE AS AN ALTERNATIVE TO BIOFUELS PRODUCTION. PART 1: BIOETHANOL

    Directory of Open Access Journals (Sweden)

    Maiara Priscilla de Souza

    2013-02-01

    Full Text Available The demand from the energy sector is one of the culminating factors to do researches that enable innovations in the biotechnology sector and to boost biofuel production. The variability of the existing feedstocks provides benefits to energy production, however, we must choose the ones that present plausible characteristics depending on the type of product that we want to obtained. In this context, it is noted that the microalgae have suitable characteristics to producing different types of fuels, depending on the type of treatment are subjected, the species being analyzed as well as the biochemical composition of the biomass. Bioethanol production from microalgae is a promising and growing energy alternative under a view that biomass of these microorganisms has an enormous biodiversity and contain high levels of carbohydrates, an indispensable factor for the bioconversion of microalgae in ethanol. Due to these factors, there is a constant search for more viable methods for pretreatment of biomass, hydrolysis and fermentation, having as one of the major aspects the approach of effectives methodologies in the ambit of quality and yield of ethanol. Therefore, we have to search to increase the interest in the developing of biofuels reconciling with the importance of using microalgae, analyzing whether these micro-organisms are capable of being used in bioethanol production.

  8. Microalgae respond differently to nitrogen availability during culturing

    Indian Academy of Sciences (India)

    2015-04-17

    Apr 17, 2015 ... Variations in the exogenous nitrogen level are known to significantly affect the physiological status and metabolism of microalgae. However, responses of red, green and yellow-green algae to nitrogen (N) availability have not been compared yet. Porphyridium cruentum, Scenedesmus incrassatulus and ...

  9. Membrane technology in microalgae cultivation and harvesting: a review.

    Science.gov (United States)

    Bilad, M R; Arafat, Hassan A; Vankelecom, Ivo F J

    2014-11-15

    Membrane processes have long been applied in different stages of microalgae cultivation and processing. These processes include microfiltration, ultrafiltration, dialysis, forward osmosis, membrane contactors and membrane spargers. They are implemented in many combinations, both as a standalone and as a coupled system (in membrane biomass retention photobioreactors (BR-MPBRs) or membrane carbonation photobioreactors (C-MPBRs). To provide sufficient background on these applications, an overview of membrane materials and membrane processes of interest in microalgae cultivation and processing is provided in this work first. Afterwards, discussion about specific aspects of membrane applications in microbial cultivation and harvesting is provided, including membrane fouling. Many of the membrane processes were shown to be promising options in microalgae cultivation. Yet, significant process optimizations are still required when they are applied to enable microalgae biomass bulk production to become competitive as a raw material for biofuel production. Recent developments of the coupled systems (BR-MPBR and C-MPBR) bring significant promises to improve the volumetric productivity of a cultivation system and the efficiency of inorganic carbon capture, respectively. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. High Lipid Induction in Microalgae for Biodiesel Production

    Directory of Open Access Journals (Sweden)

    Peer M. Schenk

    2012-05-01

    Full Text Available Oil-accumulating microalgae have the potential to enable large-scale biodiesel production without competing for arable land or biodiverse natural landscapes. High lipid productivity of dominant, fast-growing algae is a major prerequisite for commercial production of microalgal oil-derived biodiesel. However, under optimal growth conditions, large amounts of algal biomass are produced, but with relatively low lipid contents, while species with high lipid contents are typically slow growing. Major advances in this area can be made through the induction of lipid biosynthesis, e.g., by environmental stresses. Lipids, in the form of triacylglycerides typically provide a storage function in the cell that enables microalgae to endure adverse environmental conditions. Essentially algal biomass and triacylglycerides compete for photosynthetic assimilate and a reprogramming of physiological pathways is required to stimulate lipid biosynthesis. There has been a wide range of studies carried out to identify and develop efficient lipid induction techniques in microalgae such as nutrients stress (e.g., nitrogen and/or phosphorus starvation, osmotic stress, radiation, pH, temperature, heavy metals and other chemicals. In addition, several genetic strategies for increased triacylglycerides production and inducibility are currently being developed. In this review, we discuss the potential of lipid induction techniques in microalgae and also their application at commercial scale for the production of biodiesel.

  11. Cultivation of microalgae on artificial light comes at a cost

    NARCIS (Netherlands)

    Blanken, W.M.; Cuaresma Franco, M.; Wijffels, R.H.; Janssen, M.G.J.

    2013-01-01

    Microalgae are potential producers of bulk food and feed compounds, chemicals, and biofuels. To produce these bulk products competitively, it is important to keep costs of raw material low. Light energy can be provided by sun or lamps. Sunlight is free and abundant. Disadvantages of sunlight,

  12. Cultivation of microalgae in a high irradiance area

    NARCIS (Netherlands)

    Cuaresma, M.

    2011-01-01


    Microalgae are a promising source of high-value products (i.e. carotenoids, ω-3 fatty acids), as well as feedstocks for food, bulk chemicals and biofuels. Industrial production is, however, still limited because the technology needs further development. One of the main bottlenecks is the

  13. Photoacclimation state determines the photobehaviour of motile microalgae

    DEFF Research Database (Denmark)

    Ezequiel, João; Laviale, Martin; Frankenbach, Silja

    2015-01-01

    High productivity in intertidal microphytobenthic communities is achieved despite exposure to extreme and dynamic conditions (e.g. light, salinity, temperature). As an adaptation to this hostile environment, most of the microalgae species inhabiting fine-sediment habitats are motile, being able...

  14. Horizontal or vertical photobioreactors? How to improve microalgae photosynthetic efficiency

    NARCIS (Netherlands)

    Cuaresma, M.; Janssen, M.G.J.; Vilchez, C.; Wijffels, R.H.

    2011-01-01

    The productivity of a vertical outdoor photobioreactor was quantitatively assessed and compared to a horizontal reactor. Daily light cycles in southern Spain were simulated and applied to grow the microalgae Chlorella sorokiniana in a flat panel photobioreactor. The maximal irradiance around noon

  15. Continuous culture methodology for the screening of microalgae for oil.

    Science.gov (United States)

    Del Río, Esperanza; Armendáriz, Ana; García-Gómez, Elena; García-González, Mercedes; Guerrero, Miguel G

    2015-02-10

    A basic criterion in the selection of microalgae suitable as source of oil for biodiesel should be their actual capacity to produce lipids or, more properly, the fatty acid yield. Performance assessment of 10 preselected microalgae under both batch and continuous culture points to the latter approach as the most adequate for evaluating fatty acid productivity. Differences were patent in continuous culture among strains that otherwise had analogous oil accumulation potential under batch culture. Some promising strains under batch culture (like Muriella aurantiaca and Monoraphidium braunii) exhibited, however, values for actual fatty acid productivity lower than 40 mgL(-1)d(-1) in continuous regime. The analysis performed in photochemostat under continuous culture regime revealed the great potential of Chlorococcum olefaciens, Pseudokirchneriella subcapitata and Scenedesmus almeriensis as oil producing microalgae. Fatty acid productivity levels over 90 mgL(-1)d(-1) were recorded for the latter strains under moderate nitrogen limitation, conditions which led to an enrichment in saturated and monounsaturated fatty acids, a more suitable profile as raw material for biodiesel. The continuous culture methodology employed represents a sound procedure for screening microalgae for biofuel production, providing a reliable evaluation of their fatty acid production capacity, under conditions close to those of outdoor production systems. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Optimizing Carbon Dioxide Utilization for Microalgae Biofilm Cultivation

    NARCIS (Netherlands)

    Blanken, W.M.; Schaap, S.; Theobald, S.; Rinzema, A.; Wijffels, R.H.; Janssen, M.G.J.

    2017-01-01

    The loss of carbon dioxide (CO2) to the environment
    during microalgae cultivation is undesirable for both environmental
    and economic reasons. In this study, a phototrophic biofilm growth
    model was developed and validated with the objective to maximize
    both CO2 utilization efficiency

  17. Opportunities to improve the areal oil productivity of microalgae

    NARCIS (Netherlands)

    Breuer, G.; Lamers, P.P.; Janssen, M.G.J.; Wijffels, R.H.; Martens, D.E.

    2015-01-01

    Microalgae are often considered as a promising alternative source of vegetable oils. These oils can be used for food and biofuel applications. Productivities that are projected for large-scale microalgal oil production are, however, often poorly supported by scientific evidence and based on too

  18. Physicochemical approach to freshwater microalgae harvesting with magnetic particles

    Czech Academy of Sciences Publication Activity Database

    Procházková, G.; Podolová, N.; Šafařík, Ivo; Zachleder, Vilém; Brányik, T.

    2013-01-01

    Roč. 112, DEC 2013 (2013), s. 213-218 ISSN 0927-7765 R&D Projects: GA ČR(CZ) GAP503/10/1270 Institutional support: RVO:67179843 ; RVO:61388971 Keywords : microalgae * cell adhesion * magnetic beads * surface interactions * XDLVO theory Subject RIV: EH - Ecology, Behaviour; EI - Biotechnology ; Bionics (MBU-M) Impact factor: 4.287, year: 2013

  19. Insecticides induced biochemical changes in freshwater microalga Chlamydomonas mexicana.

    Science.gov (United States)

    Kumar, Muthukannan Satheesh; Kabra, Akhil N; Min, Booki; El-Dalatony, Marwa M; Xiong, Jiuqiang; Thajuddin, Nooruddin; Lee, Dae Sung; Jeon, Byong-Hun

    2016-01-01

    The effect of insecticides (acephate and imidacloprid) on a freshwater microalga Chlamydomonas mexicana was investigated with respect to photosynthetic pigments, carbohydrate and protein contents, fatty acids composition and induction of stress indicators including proline, superoxide dismutase (SOD) and catalase (CAT). C. mexicana was cultivated with 1, 5, 10, 15, 20 and 25 mg L(-1) of acephate and imidacloprid. The microalga growth increased with increasing concentrations of both insecticides up to 15 mg L(-1), beyond which the growth declined compared to control condition (without insecticides). C. mexicana cultivated with 15 mg L(-1) of both insecticides for 12 days was used for further analysis. The accumulation of photosynthetic pigments (chlorophyll and carotenoids), carbohydrates and protein was decreased in the presence of both insecticides. Acephate and imidacloprid induced the activities of superoxide dismutase (SOD) and catalase (CAT) and increased the concentration of proline in the microalga, which play a defensive role against various environmental stresses. Fatty acid analysis revealed that the fraction of polyunsaturated fatty acids decreased on exposure to both insecticides. C. mexicana also promoted 25 and 21% removal of acephate and imidacloprid, respectively. The biochemical changes in C. mexicana on exposure to acephate and imidacloprid indicate that the microalga undergoes an adaptive change in response to the insecticide-induced oxidative stress.

  20. Prospective of biodiesel production utilizing microalgae as the cell ...

    African Journals Online (AJOL)

    Microalgae are sunlight-driven miniature factories that convert atmospheric CO2 to polar and neutral lipids which after esterification can be utilized as an alternative source of petroleum. Further, other metabolic products such as bioethanol and biohydrogen produced by algal cells are also being considered for the same ...

  1. Improving microalgae for biotechnology - From genetics to synthetic biology

    Czech Academy of Sciences Publication Activity Database

    Hlavová, Monika; Turóczy, Zoltán; Bišová, Kateřina

    2015-01-01

    Roč. 33, č. 6 (2015), s. 1194-1203 ISSN 0734-9750 R&D Projects: GA MŠk EE2.3.30.0059; GA MŠk ED2.1.00/03.0110 Institutional support: RVO:61388971 Keywords : Microalgae * Genetics * Mutagenesis Subject RIV: EE - Microbiology, Virology Impact factor: 9.848, year: 2015

  2. Current status and perspectives of genome editing technology for microalgae.

    Science.gov (United States)

    Jeon, Seungjib; Lim, Jong-Min; Lee, Hyung-Gwan; Shin, Sung-Eun; Kang, Nam Kyu; Park, Youn-Il; Oh, Hee-Mock; Jeong, Won-Joong; Jeong, Byeong-Ryool; Chang, Yong Keun

    2017-01-01

    Genome editing techniques are critical for manipulating genes not only to investigate their functions in biology but also to improve traits for genetic engineering in biotechnology. Genome editing has been greatly facilitated by engineered nucleases, dubbed molecular scissors, including zinc-finger nuclease (ZFN), TAL effector endonuclease (TALEN) and clustered regularly interspaced palindromic sequences (CRISPR)/Cas9. In particular, CRISPR/Cas9 has revolutionized genome editing fields with its simplicity, efficiency and accuracy compared to previous nucleases. CRISPR/Cas9-induced genome editing is being used in numerous organisms including microalgae. Microalgae have been subjected to extensive genetic and biological engineering due to their great potential as sustainable biofuel and chemical feedstocks. However, progress in microalgal engineering is slow mainly due to a lack of a proper transformation toolbox, and the same problem also applies to genome editing techniques. Given these problems, there are a few reports on successful genome editing in microalgae. It is, thus, time to consider the problems and solutions of genome editing in microalgae as well as further applications of this exciting technology for other scientific and engineering purposes.

  3. Cultivation of micro-algae in closed tubular reactor

    Energy Technology Data Exchange (ETDEWEB)

    Gudin, C.; Bernard, A.; Chaumont, D.

    1983-11-01

    A description is presented of the three culture pilot utilities in activity under natural light, including glass tubular solar collector (30 mm diameter) in which the microalgae culture circulates. The utility is controled automatically (thermal regulation, gaseous transfers, continuous culture organization). The tests were conducted for the production of polysaccharides (Porphyridium cruentum, chlamydomonas mexicana) or hydrocarbons (Botriococcus braunii).

  4. Microalgae for the production of bulk chemicals and biofuels

    NARCIS (Netherlands)

    Wijffels, R.H.; Barbosa, M.J.; Eppink, M.H.M.

    2010-01-01

    The feasibility of microalgae production for biodiesel was discussed. Although algae are not yet produced at large scale for bulk applications, there are opportunities to develop this process in a sustainable way. It remains unlikely, however, that the process will be developed for biodiesel as the

  5. Edible oils from microalgae: insights in TAG accumulation

    NARCIS (Netherlands)

    Klok, A.J.; Lamers, P.P.; Martens, D.E.; Draaisma, R.B.; Wijffels, R.H.

    2014-01-01

    Microalgae are a promising future source for sustainable edible oils. To make microalgal oil a cost-effective alternative for common vegetable oils, increasing TAG productivity and TAG content are of high importance. Fulfilling these targets requires proper understanding of lipid metabolism in

  6. Biodiesel Production from Microalgae by Extraction – Transesterification Method

    Directory of Open Access Journals (Sweden)

    Nguyen Thi Phuong Thao

    2013-11-01

    Full Text Available The environmental impact of using petroleum fuels has led to a quest to find a suitable alternative fuel source. In this study, microalgae were explored as a highly potential feedstock to produce biodiesel fuel. Firstly, algal oil is extracted from algal biomass by using organic solvents (n–hexan.  Lipid is contained in microalgae up to 60% of their weight. Then, Biodiesel is created through a chemical reaction known as transesterification between algal oil and alcohol (methanol with strong acid (such as H2SO4 as the catalyst. The extraction – transesterification method resulted in a high biodiesel yield (10 % of algal biomass and high FAMEs content (5.2 % of algal biomass. Biodiesel production from microalgae was studied through experimental investigation of transesterification conditions such as reaction time, methanol to oil ration and catalyst dosage which are deemed to have main impact on reaction conversion efficiency. All the parameters which were characterized for purified biodiesel such as free glycerin, total glycerin, flash point, sulfur content were analyzed according to ASTM standardDoi: http://dx.doi.org/10.12777/wastech.1.1.6-9Citation:  Thao, N.T.P., Tin, N.T., and Thanh, B.X. 2013. Biodiesel Production from Microalgae by Extraction – Transesterification Method. Waste Technology 1(1:6-9. Doi: http://dx.doi.org/10.12777/wastech.1.1.6-9

  7. Microalgae harvesting via co-culture with filamentous fungus

    Science.gov (United States)

    Gultom, Sarman Oktovianus

    Microalgae harvesting is a labor- and energy-intensive process. For instance, classical harvesting technologies such as chemical addition and mechanical separation are economically prohibiting for biofuel production. Newer approaches to harvest microalgae have been developed in order to decrease costs. Among these new methods, fungal co-pelletization seems to be a promising technology. By co-culturing filamentous fungi with microalgae, it is possible to form pellets, which can easily be separated. In this study, different parameters for the cultivation of filamentous fungus (Aspergillus niger) and microalgae (Chlorella vulgaris) to efficiently form cell pellets were evaluated under heterotrophic and phototrophic conditions, including organic carbon source (glucose, glycerol and sodium acetate) concentration, pH, initial concentration of fungal spores, initial concentration of microalgal cells, concentration of ionic strength (Calcium and Magnesium) and concentration of salinity (NaCl). In addition, zeta-potential measurements were carried out in order to get a better understanding of the mechanism of attraction. It was found that 2 g/L of glucose, a fungus to microalgae ratio of 1:300, and uncontrolled pH (around 7) are the best culturing conditions for co-pelletization. Under these conditions, it was possible to achieve a high harvesting performance (>90%). In addition, it was observed that most pellets formed in the co-culture were spherical with an average diameter of 3.5 mm and in concentrations of about 5 pellets per mL of culture media. Under phototrophic conditions, co-pelletization required the addition of glucose as organic carbon source to sustain the growth of fungi and to allow the harvesting of microalgae. Zeta-potential measurements indicated that (i) both microalgae and fungi have low zeta-potential values regardless of the pH on the bulk (i.e. <-10 mV) (ii) fungi can have a positive electric charge at low pH (ie. pH=3). These values suggest that it

  8. Effect of microalgae storage conditions on methane yields.

    Science.gov (United States)

    Barreiro-Vescovo, Santiago; de Godos, Ignacio; Tomás-Pejó, Elia; Ballesteros, Mercedes; González-Fernández, Cristina

    2018-03-10

    During the last decade, a lot of research has been focused on identifying the methane yields achievable when using microalgae biomass (fresh and pretreated) as a substrate in anaerobic digestion. Encountered differences are frequently attributed to the different microalgae strains (cell walls and macromolecular profiles) or the different metabolic activities of anaerobic sludge used as inoculum. Nevertheless, under the hypothesis that the state of microalgae upon biomass storage may also play a significant role, this study was designed to evaluate the effect of biomass processing and storage on methane yields and hydrolysis kinetics in batch mode assays. Slight changes in the macromolecular profile distribution of the different tested biomass were observed. Regardless of the time that the biomass was stored, results revealed that frozen biomass doubled the hydrolysis constant and enhanced methane yield by 1.56-fold compared to fresh microalgae biomass (82.4 mL CH 4  g COD in -1 ). Similar enhancement was obtained with the freeze-dried biomass, and slightly lower values were obtained (1.34-fold) for the biomass kept at 4 °C longer than a week. Likewise, the semi-continuously operated reactor fed with microalgae biomass stored for 28 days at 4 °C did not show any effect in terms of methane production, although nitrogen mineralization was higher than expected. Remarkably, the initial stage of the biomass should be carefully considered for comparison purposes with the available literature on batch mode assays. This study highlights the importance of considering how the biomass is stored before the anaerobic digestion process to avoid misleading conclusions.

  9. Toxicity of silver and gold nanoparticles on marine microalgae.

    Science.gov (United States)

    Moreno-Garrido, Ignacio; Pérez, Sara; Blasco, Julián

    2015-10-01

    The increased use of nanomaterials in several novel industrial applications during the last decade has led to a rise in concerns about the potential toxic effects of released engineered nanoparticles (NPs) into the environment, as their potential toxicity to aquatic organisms is just beginning to be recognised. Toxicity of metallic nanoparticles to aquatic organisms, including microalgae, seems to be related to their physical and chemical properties, as well as their behaviour in the aquatic media where processes of dissolution, aggregation and agglomeration can occur. Although the production of these particles has increased considerably in recent years, data on their toxicity on microalgae, especially those belonging to marine or estuarine environments remain scarce and scattered. The literature shows a wide variation of results on toxicity, mainly due to the different methodology used in bioassays involving microalgae. These can range for up to EC50 data, in the case of AgNPs, representing five orders of magnitude. The importance of initial cellular density is also addressed in the text, as well as the need for keeping test conditions as close as possible to environmental conditions, in order to increase their environmental relevance. This review focuses on the fate and toxicity of silver, gold, and gold-silver alloy nanoparticles on microalgae, as key organisms in aquatic ecosystems. It is prompted by their increased production and use, and taking into account that oceans and estuaries are the final sink for those NPs. The design of bioassays and further research in the field of microalgae nanoecotoxicology is discussed, with a brief survey on newly developed technology of green (algae mediated) production of Ag, Au and Ag-Au bimetallic NPs, as well as some final considerations about future research on this field. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. From transient response of a compact photobioreactor for microalgae cultivation

    Energy Technology Data Exchange (ETDEWEB)

    Dilay, Emerson; Ribeiro, Robert Luis Lara; Pulliam, Raevon; Mariano, Andre Bellin [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil). Nucleo de Pesquisa e Desenvolvimento em Energia Auto-Sustentavel; Ordonez, Juan Carlos [Florida State University, Tallahassee, FL (United States). Dept. of Mechanical Engineering and Center for Advanced Power Systems], E-mail: ordonez@caps.fsu.edu; Vargas, Jose Viriato Coelho [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil). Dept. de Engenharia Mecanica

    2010-07-01

    Biofuels from microalgae are currently the subject of funded scientific research in many countries due to their high productivity of oil when compared with other crops. Microalgae can also be used in many important applications such as to obtain compounds of interest for food, chemicals, and pharmaceuticals. The high productivity of microalgae when compared with other crops is achieved because agricultural land is not mandatory for their cultivation, since they can be grown in open ponds, sea or vertical photo bioreactors. In this paper, a mathematical model is introduced for assessing the transient microalgae growth as a function of variable light intensity, temperature and environmental conditions in the daily cycle. Photo bioreactor geometry is considered as well. Light intensity is obtained from sun position, photo bioreactor geometry, and the installation location in the world. The photo bioreactor was discretized in space by the the volume element method. Balances of energy and species together with thermodynamics, heat transfer and chemistry empirical and theoretical correlations are applied to each volume element. Therefore, a system of ordinary differential equations with respect to time only is capable of delivering temperatures and concentrations as functions of space and time, even with a coarse mesh. The numerical results are capable of predicting the transient and steady state photo bioreactor biomass production with low computational time. Microalgae specific growth rate as a function of average light intensity inside the tubes and time was calculated. As a result, the model is expected to be a useful tool for simulation, design, and optimization of compact photo bioreactors. (author)

  11. Techno-economical evaluation of protein extraction for microalgae biorefinery

    Science.gov (United States)

    Sari, Y. W.; Sanders, J. P. M.; Bruins, M. E.

    2016-01-01

    Due to scarcity of fossil feedstocks, there is an increasing demand for biobased fuels. Microalgae are considered as promising biobased feedstocks. However, microalgae based fuels are not yet produced at large scale at present. Applying biorefinery, not only for oil, but also for other components, such as carbohydrates and protein, may lead to the sustainable and economical microalgae-based fuels. This paper discusses two relatively mild conditions for microalgal protein extraction, based on alkali and enzymes. Green microalgae (Chlorella fusca) with and without prior lipid removal were used as feedstocks. Under mild conditions, more protein could be extracted using proteases, with the highest yields for microalgae meal (without lipids). The data on protein extraction yields were used to calculate the costs for producing 1 ton of microalgal protein. The processing cost for the alkaline method was € 2448 /ton protein. Enzymatic method performed better from an economic point of view with € 1367 /ton protein on processing costs. However, this is still far from industrially feasible. For both extraction methods, biomass cost per ton of produced product were high. A higher protein extraction yield can partially solve this problem, lowering processing cost to €620 and 1180 /ton protein product, using alkali and enzyme, respectively. Although alkaline method has lower processing cost, optimization appears to be better achievable using enzymes. If the enzymatic method can be optimized by lowering the amount of alkali added, leading to processing cost of € 633/ton protein product. Higher revenue can be generated when the residue after protein extraction can be sold as fuel, or better as a highly digestible feed for cattle.

  12. Incorporation of lutein and docosahexaenoic acid from dietary microalgae into the retina in quail.

    Science.gov (United States)

    Schnebelen-Berthier, Coralie; Acar, Niyazi; Pouillart, Philippe; Thabuis, Clementine; Rodriguez, Bertrand; Depeint, Flore; Clerc, Elise; Mathiaud, Adeline; Bourdillon, Anne; Baert, Blandine; Bretillon, Lionel; Lecerf, Jean-Michel

    2015-03-01

    Lutein and docosahexaenoic acid (DHA) are associated with the prevention of age-related macular degeneration (AMD). Since microalgae are potent natural sources of these nutrients, their nutritional value should be evaluated based on the bioavailability of lutein and DHA for the retina via the plasmatic compartment. In this study, quail were fed for 5 months either with a diet supplemented or deprived with microalgae rich in lutein and DHA. In the microalgae-fed group, the retinal concentrations of lutein and zeaxanthin gradually increased whereas in plasma, these compounds started to increase from the first month of supplementation. We also observed a significant increase in retinal and plasmatic levels of DHA in the microalgae-fed group. In conclusion, the plasmatic and retinal contents of lutein and DHA were significantly increased in quail fed with lutein- and DHA-rich microalgae. Food fortification with microalgae may be an innovative way to increase lutein and DHA consumption in humans.

  13. Current developments in high-throughput analysis for microalgae cellular contents.

    Science.gov (United States)

    Lee, Tsung-Hua; Chang, Jo-Shu; Wang, Hsiang-Yu

    2013-11-01

    Microalgae have emerged as one of the most promising feedstocks for biofuels and bio-based chemical production. However, due to the lack of effective tools enabling rapid and high-throughput analysis of the content of microalgae biomass, the efficiency of screening and identification of microalgae with desired functional components from the natural environment is usually quite low. Moreover, the real-time monitoring of the production of target components from microalgae is also difficult. Recently, research efforts focusing on overcoming this limitation have started. In this review, the recent development of high-throughput methods for analyzing microalgae cellular contents is summarized. The future prospects and impacts of these detection methods in microalgae-related processing and industries are also addressed. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Control of predators in industrial scale microalgae cultures with Pulsed Electric Fields.

    Science.gov (United States)

    Rego, D; Redondo, L M; Geraldes, V; Costa, L; Navalho, J; Pereira, M T

    2015-06-01

    This work describes the utilization of Pulsed Electric Fields to control the protozoan contamination of a microalgae culture, in an industrial 2.7 m(3) microalgae photobioreactor. The contaminated culture was treated with Pulsed Electric Fields, PEF, for 6h with an average of 900 V/cm, 65 μs pulses of 50 Hz. Working with recirculation, all the culture was uniformly exposed to the PEF throughout the assay. The development of the microalgae and protozoan populations was followed and the results showed that PEF is effective on the selective elimination of protozoa from microalgae cultures, inflicting on the protozoa growth halt, death or cell rupture, without affecting microalgae productivity. Specifically, the results show a reduction of the active protozoan population of 87% after 6h treatment and 100% after few days of normal cultivation regime. At the same time, microalgae growth rate remained unaffected. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Application of agar liquid-gel transition in cultivation and harvesting of microalgae for biodiesel production.

    Science.gov (United States)

    Kumar, Vinod; Nanda, Manisha; Verma, Monu

    2017-11-01

    In order to increase microalgal biomass productivity efficient cultivation and harvesting methods are needed against the available traditional methods. The present study focuses on the same by harvesting microalgae using agar gel. Agar medium containing bold's basal medium (BBM) undergoes a thermoreversible gel transition. As compared to the traditional protocols, this gel is used to cultivate microalgae without even affecting the total productivity. To develop the gel for microalgae cultivation, agar was boiled in BBM. Then the agar was cooled to 35°C and microalgae culture was added to it. After seeding the microalgae the temperature of the agar was further decreased by 10°C to induce gelation. Instead of isolated cells microalgae were grown in clusters within the agar gel. Microalgal clusters gravimetrically settle at the bottom within 2h. In this method agar can be reused. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Inmovilización de las microalgas Scenedesmus ovalternus (Scenedesmaceae y Chlorella vulgaris (Chlorellaceae en esferas de alginato de calcio.

    Directory of Open Access Journals (Sweden)

    Mario Andres Forero-Cujiño

    2016-05-01

    Full Text Available En este trabajo se describe la técnica de inmovilización de microalgas en esferas de alginato de calcio. Se emplearon las especies Scenedesmus ovalternus y Chlorella vulgaris, se determinó la estabilidad de las esferas, la cinética de crecimiento y la concentración de las microalgas en el interior de las esferas. Chlorella vulgaris alcanzó mayores densidades poblacionales y tasas de crecimiento más altas cuando se inmovilizó en concentraciones del 10 % v/v con el alginato (1,31*106 cél/ml. Para Scenedesmus ovalternus se observó una mayor densidad poblacional y una mayor tasa de crecimiento cuando se inmovilizó en concentraciones del 20 % v/v (7,06*105 cél/ml. Estos resultados son útiles para aplicaciones prácticas de las algas encapsuladas, tales como el biomonitoreo o la biorremediación.

  17. Las microalgas de Tillandsia multicaulis Steud. (Bromeliaceae de la Reserva Ecológica “La Martinica”, Veracruz

    Directory of Open Access Journals (Sweden)

    Brisceida Hernández-Rodríguez

    2014-01-01

    Full Text Available Las bromelias tienen la capacidad de retener agua en las axilas de las hojas lo que es conocido como tanques o fitotelmata; mantienen cadenas tróficas complejas con todo tipo de organismos, desde bacterias hasta vertebrados pequeños. En este trabajo, presentamos la primera aproximación a las microalgas que viven en las cisternas de una especie de bromelia en la Reserva Ecológica “La Martinica” en Banderilla, Veracruz. Las recolecciones se estudiaron en material preservado y en cultivos. Se obtuvieron cerca de 60 algas pertenecientes a las Cyanoprokariota, Euglenophyta, Cryptophyta, Chlorophyta y Bacillariophyta, sin embargo, solo se lograron identificar 16 especies. Se concluye que los tanques de Tillandsia multicaulis brindan las condiciones adecuadas para el desarrollo de microalgas y que la ubicación y la morfología de la bromelia influyen en la distribución de este grupo biológico. La escasez de individuos en las muestras analizadas no permitió una identificación precisa de todas las especies. En los cultivos aparecieron especies no observadas en el material preservado, lo que indica una flora mucho más rica de la que puede observarse directamente.

  18. Effects of Fluctuating Environments on the Selection of High Yielding Microalgae

    Energy Technology Data Exchange (ETDEWEB)

    Benemann, J. R.; Tillett, D. M.

    1987-02-27

    Microalgae have the potential of producing biomass with a high content of lipids at high productivities using seawater or saline ground water resources. Microalgal lipids are similar to vegetable oils and suitable for processing to liquid fuels. Engineering cost analysis studies have concluded that, at a favorable site, microalgae cultivation for fuel production could be economically viable. The major uncertainties involve the microalgae themselves: biomass and lipid productivity and culture stability.

  19. Chitosan and Its Derivatives Applied in Harvesting Microalgae for Biodiesel Production: An Outlook

    OpenAIRE

    Guanyi Chen; Liu Zhao; Yun Qi; Yuan-Lu Cui

    2014-01-01

    Although oil-accumulating microalgae are a promising feedstock for biodiesel production, large-scale biodiesel production is not yet economically feasible. As harvesting accounts for an important part of total production cost, mass production of microalgae biodiesel requires an efficient low-energy harvesting strategy so as to make biodiesel production economically attractive. Chitosan has emerged as a favorable flocculating agent in harvesting of microalgae. The aim of this paper is to revie...

  20. Effect of Metals, Metalloids and Metallic Nanoparticles on Microalgae Growth and Industrial Product Biosynthesis: A Review

    OpenAIRE

    Miazek, Krystian; Iwanek, Waldemar; Remacle, Claire; Richel, Aurore; Goffin, Dorothée

    2015-01-01

    Microalgae are a source of numerous compounds that can be used in many branches of industry. Synthesis of such compounds in microalgal cells can be amplified under stress conditions. Exposure to various metals can be one of methods applied to induce cell stress and synthesis of target products in microalgae cultures. In this review, the potential of producing diverse biocompounds (pigments, lipids, exopolymers, peptides, phytohormones, arsenoorganics, nanoparticles) from microalgae cultures...

  1. Isolation and Fatty Acid Profile of Selected Microalgae Strains from the Red Sea for Biofuel Production

    OpenAIRE

    Hugo Pereira; Luísa Barreira; Luísa Custódio; Salman Alrokayan; Fouzi Mouffouk; João Varela; Khalid M. Abu-Salah; Radhouan Ben-Hamadou

    2013-01-01

    The isolation of lipid-rich autochthonous strains of microalgae is a crucial stage for the development of a microalgae-based biofuel production plant, as these microalgae already have the necessary adaptations to withstand competition, predation and the temperatures observed at each production site. This is particularly important in extreme climates such as in Saudi Arabia. Resorting to fluorescence activated cell sorting (FACS) we screened for and isolated several microalgal strains from sam...

  2. Examination of Triacylglycerol Biosynthetic Pathways via De Novo Transcriptomic and Proteomic Analyses in an Unsequenced Microalga

    Science.gov (United States)

    2011-10-17

    using a variety of water sources, including fresh, brackish, saline, and waste water [1,4,5]. At current production levels, oleaginous microalgae also...underpinnings of microalgal biology than any other microalga to date. However, this species lacks the intrinsic high-lipid productivity of many oleaginous...Examination of Triacylglycerol Biosynthetic Pathways via De Novo Transcriptomic and Proteomic Analyses in an Unsequenced Microalga Michael T

  3. Diseño de una crema para masajes con extracto de spirulina cubana Design of Cuban spirulin extract-derived massage cream

    OpenAIRE

    Ivone Almirall Díaz; Tania Fernández Cárdenas; Hilda Ma González San Miguel; Mayelín Díaz González

    2005-01-01

    La spirulina constituye la microalga de mayor uso en Cuba y una de las más importantes en el ámbito mundial por su alto contenido proteico y poseer una excelente mezcla de vitaminas, minerales y agentes antioxidantes que protegen al organismo contra la acción nociva de los radicales libres. Por estas razones se ha incursionado en la elaboración de productos cosméticos destinados al cuidado de la piel con la utilización del principio bioactivo del extracto hidroalcohólico de esta microalga. Se...

  4. Transgene expression in microalgae – from tools to applications

    Directory of Open Access Journals (Sweden)

    Lior eDoron

    2016-04-01

    Full Text Available Microalgae comprise a biodiverse group of photosynthetic organisms that reside in water sources and sediments. The green microalgae Chlamydomonas reinhardtii was adopted as a useful model organism for studying various physiological systems. Its ability to grow under both photosynthetic and heterotrophic conditions allows efficient growth of non-photosynthetic mutants, making Chlamydomonas a useful genetic tool to study photosynthesis. In addition, this green alga can grow as haploid or diploid cells, similar to yeast, providing a powerful genetic system. As a result, easy and efficient transformation systems have been developed for Chlamydomonas, targeting both the chloroplast and nuclear genomes. Since microalgae comprise a rich repertoire of species that offer variable advantages for biotech and biomed industries, gene transfer technologies were further developed for many microalgae to allow for the expression of foreign proteins of interest. Expressing foreign genes in the chloroplast enables the targeting of foreign DNA to specific sites by homologous recombination. Chloroplast transformation also allows for the introduction of genes encoding several enzymes from a complex pathway, possibly as an operon. Expressing foreign proteins in the chloroplast can also be achieved by introducing the target gene into the nuclear genome, with the protein product bearing a targeting signal that directs import of the transgene-product into the chloroplast, like other endogenous chloroplast proteins. Integration of foreign genes into the nuclear genome is mostly random, resulting in large variability between different clones, such that extensive screening is required. The use of different selection modalities is also described, with special emphasis on the use of herbicides and metabolic markers which are considered to be friendly to the environment, as compared to drug-resistance genes that are commonly used. Finally, despite the development of a wide

  5. Effect of Metals, Metalloids and Metallic Nanoparticles on Microalgae Growth and Industrial Product Biosynthesis: A Review

    Directory of Open Access Journals (Sweden)

    Krystian Miazek

    2015-10-01

    Full Text Available Microalgae are a source of numerous compounds that can be used in many branches of industry. Synthesis of such compounds in microalgal cells can be amplified under stress conditions. Exposure to various metals can be one of methods applied to induce cell stress and synthesis of target products in microalgae cultures. In this review, the potential of producing diverse biocompounds (pigments, lipids, exopolymers, peptides, phytohormones, arsenoorganics, nanoparticles from microalgae cultures upon exposure to various metals, is evaluated. Additionally, different methods to alter microalgae response towards metals and metal stress are described. Finally, possibilities to sustain high growth rates and productivity of microalgal cultures in the presence of metals are discussed.

  6. Microalgae community shifts during the biogas upgrading in an alkaline open photobioreactor.

    Science.gov (United States)

    Granada-Moreno, C I; Aburto-Medina, A; de Los Cobos Vasconcelos, D; González-Sánchez, A

    2017-10-01

    To achieve the functional specialization of a microalgae community through operational tuning of an open photobioreactor used for biogas upgrading under alkaline conditions. An open photobioreactor was inoculated with an indigenous microalgae sample from the Texcoco Soda Lake. A microalgae community was adapted to fix CO 2 from synthetic biogas through different culture conditions reaching a maximum of 220 mg CO 2  l -1 per day. Picochlorum sp. and Scenedesmus sp. were identified as the prominent microalgae genera by molecular fingerprinting (partial sequencing of 16S rRNA and 18S rRNA genes) but only the first was detected by microscopy screening. Changes in the microalgae community profile were monitored by a range-weighted richness index, reaching the lowest value when biogas was upgraded. A robust microalgae community in the open photobioreactor was obtained after different culture conditions. The specialization of microalgae community for CO 2 fixation under H 2 S presence was driven by biogas upgrading conditions. The alkaline conditions enhance the CO 2 absorption from biogas and could optimize specialized microalgae communities in the open photobioreactor. Denaturing gradient gel electrophoresis fingerprinting and richness index comparison are useful methods for the evaluation of microalgae community shifts and photosynthetic activity performance, particularly in systems intended for CO 2 removal from biogas where the CO 2 assimilation potential can be related to the microbial richness. © 2017 The Society for Applied Microbiology.

  7. Potential of microalgae in the bioremediation of water with chloride content

    OpenAIRE

    Ramírez, M. E.; Vélez, Y. H.; Rendón, L.; Alzate, E.

    2017-01-01

    Abstract In this work it was carried out the bioremediation of water containing chlorides with native microalgae (MCA) provided by the Centre for study and research in biotechnology (CIBIOT) at Universidad Pontificia Bolivariana. Microalgae presented an adaptation to the water and so the conditions evaluated reaching a production of CO2 in mg L-1 of 53.0, 26.6, 56.0, 16.0 and 30.0 and chloride removal efficiencies of 16.37, 26.03, 40.04, 25.96 and 20.25% for microalgae1, microalgae2, microalg...

  8. A Method for Microalgae Proteomics Analysis Based on Modified Filter-Aided Sample Preparation.

    Science.gov (United States)

    Li, Song; Cao, Xupeng; Wang, Yan; Zhu, Zhen; Zhang, Haowei; Xue, Song; Tian, Jing

    2017-11-01

    With the fast development of microalgal biofuel researches, the proteomics studies of microalgae increased quickly. A filter-aided sample preparation (FASP) method is widely used proteomics sample preparation method since 2009. Here, a method of microalgae proteomics analysis based on modified filter-aided sample preparation (mFASP) was described to meet the characteristics of microalgae cells and eliminate the error caused by over-alkylation. Using Chlamydomonas reinhardtii as the model, the prepared sample was tested by standard LC-MS/MS and compared with the previous reports. The results showed mFASP is suitable for most of occasions of microalgae proteomics studies.

  9. Simulation of temperature effect on microalgae culture in a tubular photo bioreactor for local solar irradiance

    Science.gov (United States)

    Shahriar, M.; Deb, Ujjwal Kumar; Rahman, Kazi Afzalur

    2017-06-01

    Microalgae based biofuel is now an emerging source of renewable energy alternative to the fossil fuel. This paper aims to present computational model of microalgae culture taking effect of solar irradiance and corresponding temperature in a photo bioreactor (PBR). As microalgae is a photosynthetic microorganism, so irradiance of sunlight is one of the important limiting factors for the proper growth of microalgae cells as temperature is associated with it. We consider the transient behaviour of temperature inside the photo bioreactor for a microalgae culture. The optimum range of temperature for outdoor cultivation of microalgae is about 16-35°c and out of this range the cell growth inhibits. Many correlations have already been established to investigate the heat transfer phenomena inside a tubular PBR. However, none of them are validated yet numerically by using a user defined function in a simulated model. A horizontal tubular PBR length 20.5m with radius 0.05m has taken account to investigate the temperature effect for the growth of microalgae cell. As the solar irradiance varies at any geographic latitude for a year so an empirical relation is established between local solar irradiance and temperature to simulate the effect. From our simulation, we observed that the growth of microalgae has a significant effect of temperature and the solar irradiance of our locality is suitable for the culture of microalgae.

  10. Detection of viability of micro-algae cells by optofluidic hologram pattern.

    Science.gov (United States)

    Wang, Junsheng; Yu, Xiaomei; Wang, Yanjuan; Pan, Xinxiang; Li, Dongqing

    2018-03-01

    A rapid detection of micro-algae activity is critical for analysis of ship ballast water. A new method for detecting micro-algae activity based on lens-free optofluidic holographic imaging is presented in this paper. A compact lens-free optofluidic holographic imaging device was developed. This device is mainly composed of a light source, a small through-hole, a light propagation module, a microfluidic chip, and an image acquisition and processing module. The excited light from the light source passes through a small hole to reach the surface of the micro-algae cells in the microfluidic chip, and a holographic image is formed by the diffraction light of surface of micro-algae cells. The relation between the characteristics in the hologram pattern and the activity of micro-algae cells was investigated by using this device. The characteristics of the hologram pattern were extracted to represent the activity of micro-algae cells. To demonstrate the accuracy of the presented method and device, four species of micro-algae cells were employed as the test samples and the comparison experiments between the alive and dead cells of four species of micro-algae were conducted. The results show that the developed method and device can determine live/dead microalgae cells accurately.

  11. Effect of Metals, Metalloids and Metallic Nanoparticles on Microalgae Growth and Industrial Product Biosynthesis: A Review.

    Science.gov (United States)

    Miazek, Krystian; Iwanek, Waldemar; Remacle, Claire; Richel, Aurore; Goffin, Dorothee

    2015-10-09

    Microalgae are a source of numerous compounds that can be used in many branches of industry. Synthesis of such compounds in microalgal cells can be amplified under stress conditions. Exposure to various metals can be one of methods applied to induce cell stress and synthesis of target products in microalgae cultures. In this review, the potential of producing diverse biocompounds (pigments, lipids, exopolymers, peptides, phytohormones, arsenoorganics, nanoparticles) from microalgae cultures upon exposure to various metals, is evaluated. Additionally, different methods to alter microalgae response towards metals and metal stress are described. Finally, possibilities to sustain high growth rates and productivity of microalgal cultures in the presence of metals are discussed.

  12. Desenvolvimento de bezerros leiteiros alimentados com silagem de leite de transição: I - Trato digestivo

    Directory of Open Access Journals (Sweden)

    R.A. Azevedo

    2014-04-01

    Full Text Available Avaliou-se o desenvolvimento do trato digestivo de bezerros Holandeses aleitados com silagem de leite de transição. Foram utilizados 18 animais, com peso corporal inicial médio de 36,50kg (±4,03, alimentados individualmente em baias com concentrado, feno de Cynodon sp., água e suplemento mineral oferecidos ad libitum. O delineamento experimental foi inteiramente ao acaso, com três tratamentos e seis repetições. Os tratamentos consistiram em leite integral e silagem de leite de transição diluída em água ou misturada em leite, correspondendo a quatro litros diários divididos em duas refeições, durante 59 dias. Aos 60 dias, os bezerros foram abatidos e realizaram-se pesagens do trato digestivo e medidas histológicas das papilas ruminais. O sistema de aleitamento não interferiu nos consumos de concentrado e matéria seca total e no desenvolvimento de papilas ruminais (P>0,05. A silagem de leite de transição diluída em água resultou em menor peso corporal, menor peso corporal vazio e absoluto do abomaso e maior desenvolvimento intestinal. O aleitamento com silagem misturada em leite não comprometeu o desenvolvimento corporal e do trato digestivo até 60 dias de idade, representando alternativa ao aleitamento com leite.

  13. Larvicultura de Rhamdia quelen (Pisces, Pimelodidae con proteína vegetal y animal, suplementadas con plancton

    Directory of Open Access Journals (Sweden)

    Germán Castañeda A.

    2011-12-01

    Full Text Available Objetivo. Determinar el efecto de dietas con diferentes proporciones de fuentes proteicas animales y vegetales suplementadas con plancton sobre el crecimiento y sobrevivencia en larvas de Rhamdia quelen. Materiales y métodos. Fueron formuladas dos dietas experimentales, dieta-1 con 70% de proteína de origen vegetal (torta de soya y dieta-2 con 70% de proteína proveniente de animales (corazón bovino yharina de pescado; se utilizaron cuatro protocolos de alimentación (cinco réplicas por tratamiento: dieta-1 + plancton filtrado en tamiz de 50-200 micras (T1, dieta-2 + plancton filtrado en tamiz de 50-200 micras (T2, dieta-1 (T3, dieta-2 (T4. Las larvas fueron manejadas a una densidad de 20 animales L-1 suministrando alimentohasta aparente saciedad diariamente a las 07:00, 11:00, 16:00 y 21:00 horas; la suplementación con plancton se realizó a las 11:00 y 21:00 horas. Resultados. Entre T1 y T2 no se observaron diferencias estadísticas (p>0.05 en peso final (21.89 ± 15.17mg vs 20.37 ± 10.37mg, longitud total (13.41±2.34mm vs 13.39±1.99 mm, factor de condición (K (0.80±0.13 vs 0.78±0.13 y sobrevivencia (46.6±2.68% vs36.0±7.41%; las diferencias entre T3 y T4 tampoco fueron significativas (3.35±1.40 mg vs 2.98±1.48 mg; 7.54±0.91mm vs 7.33±0.96mm; 0.75±0.13 vs 0.71±0.12; 33.6±9.07% vs 24.8±6.76%, respectivamente; hubo diferencias significativas (p<0.05 entre los grupos suplementados con plancton y los alimentados solo con ración. Conclusiones. La suplementación con plancton fue más efectiva que elofrecimiento solo de ración. La inclusión del 62.9% de torta de soya en la formulación (T1, aparentemente no afectó el crecimiento ni la sobrevivencia.

  14. Anaerobic digestate as substrate for microalgae culture: the role of ammonium concentration on the microalgae productivity.

    Science.gov (United States)

    Uggetti, Enrica; Sialve, Bruno; Latrille, Eric; Steyer, Jean-Philippe

    2014-01-01

    In spite of the increasing interest received by microalgae as potential alternatives for biofuel production, the technology is still not industrially viable. The utilization of digestate as carbon and nutrients source can enhance microalgal growth reducing costs and environmental impacts. This work assesses microalgal growth utilizing the liquid phase of anaerobic digestate effluent as substrate. The effect of inoculum/substrate ratio on microalgal growth was studied in a laboratory batch experiment conduced in 0.5L flasks. Results suggested that digestate may be an effective substrate for microalgal growth promoting biomass production up to 2.6 gTSS/L. Microalgal growth rate was negatively affected by a self-shading phenomenon, while biomass production was positively correlated with the inoculum and substrate concentrations. Thus, the increasing of both digestate and microalgal initial concentration may reduce the initial growth rate (μ from 0.9 to 0.04 d(-1)) but significantly enhances biomass production (from 0.1 to 2.6 gTSS/L). Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Microalgae for economic applications: advantages and perspectives for bioethanol.

    Science.gov (United States)

    Simas-Rodrigues, Cíntia; Villela, Helena D M; Martins, Aline P; Marques, Luiza G; Colepicolo, Pio; Tonon, Angela P

    2015-07-01

    Renewable energy has attracted significant interest in recent years as a result of sustainability, environmental impact, and socio-economic considerations. Given existing technological knowledge and based on projections relating to biofuels derived from microalgae, microalgal feedstock is considered to be one of the most important renewable energy sources potentially available for industrial production. Therefore, this review examines microalgal bioethanol technology, which converts biomass from microalgae to fuel, the chemical processes involved, and possible ways of increasing the bioethanol yield, such as abiotic factors and genetic manipulation of fermenting organisms. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  16. Nutritional Evaluation of Australian Microalgae as Potential Human Health Supplements

    Science.gov (United States)

    Kent, Megan; Welladsen, Heather M.; Mangott, Arnold; Li, Yan

    2015-01-01

    This study investigated the biochemical suitability of Australian native microalgal species Scenedesmus sp., Nannochloropsis sp., Dunaliella sp., and a chlorophytic polyculture as nutritional supplements for human health. The four microalgal cultures were harvested during exponential growth, lyophilized, and analysed for proximate composition (moisture, ash, lipid, carbohydrates, and protein), pigments, and amino acid and fatty acid profiles. The resulting nutritional value, based on biochemical composition, was compared to commercial Spirulina and Chlorella products. The Australian native microalgae exhibited similar, and in several cases superior, organic nutritional properties relative to the assessed commercial products, with biochemical profiles rich in high-quality protein, nutritious polyunsaturated fats (such as α-linolenic acid, arachidonic acid, and eicosapentaenoic acid), and antioxidant pigments. These findings indicate that the microalgae assessed have great potential as multi-nutrient human health supplements. PMID:25723496

  17. Biodiesel production from microalgae oil catalyzed by a recombinant lipase.

    Science.gov (United States)

    Huang, Jinjin; Xia, Ji; Jiang, Wei; Li, Ying; Li, Jilun

    2015-03-01

    A recombinant Rhizomucor miehei lipase was constructed and expressed in Pichia pastoris. The target enzyme was termed Lipase GH2 and it can be used as a free enzyme for catalytic conversion of microalgae oil mixed with methanol or ethanol for biodiesel production in an n-hexane solvent system. Conversion rates of two major types of biodiesel, fatty acid methyl ester (FAME) and fatty acid ethyl ester (FAEE), reached maximal values (>90%) after 24h. The process of FAME production is generally more simple and economical than that of FAEE production, even though the two processes show similar conversion rates. In spite of the damaging effect of ethanol on enzyme activity, we successfully obtained ethyl ester by the enzymatic method. Our findings indicate that Lipase GH2 is a useful catalyst for conversion of microalgae oil to FAME or FAEE, and this system provides efficiency and reduced costs in biodiesel production. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Harvesting and processing of microalgae biomass fractions for biodiesel production

    International Nuclear Information System (INIS)

    Munir, M.; Sharif, N.; Naz, S.; Saleem, F.; Manzoor, F.

    2013-01-01

    There has been a recent resurgent interest in microalgae as an oil producer for biofuel applications. An adequate supply of nutrients and carbon dioxide enables algae to successfully transform light energy of the sun into energy - rich chemical compounds through photosynthesis. A strain with high lipids, successfully grown and harvested, could provide oil for most of our process by volume, which would then provide the most profitable output. Significant advances have also been made in upstream processing to generate cellular biomass and oil. However, the process of extracting and purifying of oil from algae continues to prove a significant challenge in producing both microalgae bioproducts and biofuel, as the oil extraction from algae is relatively energy-intensive and expensive. The aim of this review is to focus on different harvesting and extraction processes of algae for biodiesel production reported within the last decade. (author)

  19. In situ transesterification of highly wet microalgae using hydrochloric acid.

    Science.gov (United States)

    Kim, Bora; Im, Hanjin; Lee, Jae W

    2015-06-01

    This study addresses in situ transesterification of highly wet microalgae with hydrochloric acid (HCl) as a catalyst. In situ transesterification was performed by heating the mixture of wet algal cells, HCl, methanol, and solvent in one pot, resulting in the fatty acid methyl ester (FAME) yield over 90% at 95°C. The effects of reaction variables of temperature, amounts of catalyst, reactant, and solvent, and type of solvents on the yield were investigated. Compared with the catalytic effect of H2SO4, in situ transesterification using HCl has benefits of being less affected by moisture levels that are as high as or above 80%, and requiring less amounts of catalyst and solvent. For an equimolar amount of catalyst, HCl showed 15wt.% higher FAME yield than H2SO4. This in situ transesterification using HCl as a catalyst would help to realize a feasible way to produce biodiesel from wet microalgae. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Hazard and risk of herbicides for marine microalgae.

    Science.gov (United States)

    Sjollema, Sascha B; Martínezgarcía, Gema; van der Geest, Harm G; Kraak, Michiel H S; Booij, Petra; Vethaak, A Dick; Admiraal, Wim

    2014-04-01

    Due to their specific effect on photosynthesis, herbicides pose a potential threat to coastal and estuarine microalgae. However, comprehensive understanding of the hazard and risk of these contaminants is currently lacking. Therefore the aim of the present study was to investigate the toxic effects of four ubiquitous herbicides (atrazine, diuron, Irgarol(®)1051 and isoproturon) and herbicide mixtures on marine microalgae. Using a Pulse Amplitude Modulation (PAM) fluorometry based bioassay we demonstrated a clear species and herbicide specific toxicity and showed that the current environmental legislation does not protect algae sufficiently against diuron and isoproturon. Although a low actual risk of herbicides in the field was demonstrated, monitoring data revealed that concentrations occasionally reach potential effect levels. Hence it cannot be excluded that herbicides contribute to observed changes in phytoplankton species composition in coastal waters, but this is likely to occur only occasionally. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. Microalgae: a new alternative raw material for biodiesel production

    Energy Technology Data Exchange (ETDEWEB)

    Gouveia, L.; Rosa, F. [Instituto Nacional de Engenharia, Tecnologia e Inovacao -INETI-DER- Unidade Biomassa. Estrada do Paco do Lumiar, 1649-038 Lisboa (Portugal); Melo, A. [Faculdade de Ciencias, Universidade de Lisboa, 1749-016 Lisboa (Portugal); Medeiros, R. [Universidade Lusofona de Humanidades e Tecnologias, Campo Grande, n. 376, Lisboa (Portugal); Oliveira, A. [Extensao da Escola Superior de Biotecnologia em Caldas da Rainha, Universidade Catolica Portuguesa, Rua Mestre Mateus Fernandes, 2500-237 Caldas da Rainha (Portugal)

    2008-07-01

    Biofuels will play an increasingly important role in diversifying energy supplies to meet the world's growing energy needs. Algae are considered a promising potential feedstock for next-generation biofuels because certain species contain high amounts of oil, which could be extracted, processed and refined into transportation fuels using currently available technology. Other benefits of algae as a potential feedstock are their abundance and fast growth rates. Key technical challenges include identifying the strains with the highest oil content and growth rates and developing cost-effective growing and harvesting methods. In this work, a microalgae screening in terms of oil quantity and composition were done in order to choose the best one as oil source for biodiesel production. Oil extraction procedure was optimized and the oil obtained from each microalgae analyzed in terms of fatty acid profile and of some parameters that can influenced the biodiesel production process and the final product quality.

  2. Shaking and Blending Effect on Microalgae Concentrates Size

    Directory of Open Access Journals (Sweden)

    LUDI PARWADANI AJI

    2012-03-01

    Full Text Available Microalgae concentrates (paste can be used as an alternative feed to replace live microalgae for aquaculture due to its nutritional value and convenience. However, the clumping of cells and negative buoyancy of algae concentrate can affect bivalve culture as bivalves only capture particles in suspension and ingest a certain size range of particles. This study investigated the effect of shaking and blending treatments on the preparation of food suspensions prepared from algae concentrates (Isochrysis and Pavlova. The results indicated that the higher the shaking time (5, 10, and 15 times or blending time (10, 30, and 60 seconds, the smaller was the diameter of the resulting algae particles. Moreover, the greater the volume of algae concentrate used in preparation, the larger the diameter of algae particles produced. Shaking may be the best option because it is cheaper and simpler. However, all the treatments provided a suitable particle size range for ingestion by bivalves.

  3. Potential Production of Polyunsaturated Fatty Acids from Microalgae

    Directory of Open Access Journals (Sweden)

    Noer Abyor Handayani

    2011-07-01

    Full Text Available Currently, public awareness of healthcare importance increase. Polyunsaturated fatty acid is an essential nutrition for us, such arachidonic acid, docosahexaenoic acid and eicosapentaenoic acid. The need of Polyunsaturated fatty acid generally derived from fish oil, but fish oil has a high risk chemical contamination. Microalgae are single cell microorganism, one of Phaeodactylum tricornutum which have relatively high content of eicosapentaenoic acid (29,8%. Biotechnology market of Polyunsaturated fatty acid is very promising for both foods and feeds, because the availability of abundant raw materials and suitable to develop in the tropics. This literature review discusses about the content of Polyunsaturated fatty acid in microalgae, omega-3, omega-6, Polyunsaturated fatty acid production processes, and applications in public health

  4. Enzymatic transesterification of lipids from microalgae into biodiesel: a review

    Directory of Open Access Journals (Sweden)

    Maria del Pilar Rodriguez

    2016-10-01

    Full Text Available Biodiesel is considered as a potential interesting alternative diesel substitute due to its many advantages, such as biodegradability and non-toxicity. Biodiesel production worldwide is low and does not meet the needs of society. Therefore, biodiesel production policies have been implemented by various countries. This paper addresses the issues of plant materials containing lipids for biodiesel production and explores also the avenue of microalgae as an alternative. Various conversion technologies of lipids into biodiesel are also described and compared. Enzymatic transesterification would be most appropriate when microalgae oils are used because of their high free fatty acids content. The optimization of the enzymatic process depends on several parameters such as the catalyst, temperature, reaction time and the alcohol: oil molar ratio.

  5. Microalgae for the prevention of cardiovascular disease and stroke.

    Science.gov (United States)

    Raposo, Maria Filomena de Jesus; de Morais, Alcina Maria Miranda Bernardo

    2015-03-15

    This review focuses on and discusses the primary phytochemicals present in microalgal biomass - carotenoids, phenolic compounds, antioxidant vitamins, sterols, and polyunsaturated fatty acids - and also on the exopolysaccharides, which are produced by some types of microalgae and may play a significant role in the prevention of cardiovascular diseases (CVD) and strokes. We have listed several preclinical trials and clinical studies supporting the health benefits that most of these compounds may provide. Microalgae are very easy to grow and are not vulnerable to contaminants when grown under controlled conditions. Proper handling and growth conditions may improve the production of phytochemicals. Therefore, they may represent an excellent source of nutraceuticals and food supplements once their safety as a food supplement has been confirmed. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. Abiotic stresses as tools for metabolites in microalgae.

    Science.gov (United States)

    Paliwal, Chetan; Mitra, Madhusree; Bhayani, Khushbu; Bharadwaj, S V Vamsi; Ghosh, Tonmoy; Dubey, Sonam; Mishra, Sandhya

    2017-11-01

    Microalgae, due to various environmental stresses, constantly tune their cellular mechanisms to cope with them. The accumulation of the stress metabolites is closely related to the changes occurring in their metabolic pathways. The biosynthesis of metabolites can be triggered by a number of abiotic stresses like temperature, salinity, UV- radiation and nutrient deprivation. Although, microalgae have been considered as an alternative sustainable source for nutraceutical products like pigments and omega-3 polyunsaturated fatty acids (PUFAs) to cater the requirement of emerging human population but inadequate biomass generation makes the process economically impractical. The stress metabolism for carotenoid regulation in green algae is a 2-step metabolism. There are a few major stresses which can influence the formation of phycobiliprotein in cyanobacteria. This review would primarily focus on the cellular level changes under stress conditions and their corresponding effects on lipids (including omega-3 PUFAs), pigments and polymers. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Developing Molecular Tools To Genetically Engineer The Microalga Nannochloropsis

    OpenAIRE

    Anley, Kominist Asmamaw

    2015-01-01

    The main objective of this thesis was to develop an efficient transformation protocol for Nannochloropsis oceanica CCMP1779 by biolistic transformation using the linearized pSELECT100 plasmid which confers hygromycin B resistance. In addition the toxicity of several antibiotics for different Nannochloropsis species was determined. Nannochloropsis is the genus of unicellular photosynthetic microalgae in the class of Eustigmatophyceae, which have industrial significance due to their producti...

  8. Applications of Diatoms as Potential Microalgae in Nanobiotechnology

    OpenAIRE

    Ahmad Yari Khosroushahi; Miguel de la Guardia; Mohamad Moradi Ghorakhlu; Ali Akbar Jamali; Fariba Akbari

    2012-01-01

    Introduction: Diatoms are single cell eukaryotic microalgae, which present in nearly every water habitat make them ideal tools for a wide range of applications such as oil explora­tion, forensic examination, environmental indication, biosilica pattern generation, toxicity testing and eutrophication of aqueous ecosystems. Methods: Essential information on diatoms were reviewed and discussed towards impacts of diatoms on biosynthesis and bioremediation. Results: In this review, we present the ...

  9. The Temperature Response of Compact Tubular Microalgae Protobioreactors

    OpenAIRE

    Ribeiro, Robert Luis Lara; Mariano, André Bellin; Dilay, Emerson; Souza, Jeferson Avila; Ordonez, Juan Carlos; Vargas, Jose Viriato Coelho

    2009-01-01

    A mathematical and computational modeling of a photobioreactor for the determination of the transient temperature behavior in compact tubular microalgae photobioreactors is presented. The model combines theoretical concepts of thermodynamics with classical theoretical and empirical correlations of Fluid Mechanics and Heat Transfer. The physical domain is discretized with the Volume Element Model (VEM) through which the physical system (reactor pipes) is divided into lumped volumes, such...

  10. Hypolipidemic, Antioxidant and Antiinflammatory Activities of Microalgae Spirulina

    OpenAIRE

    Deng, Ruitang; Chow, Te-Jin

    2010-01-01

    Spirulina is free-floating filamentous microalgae growing in alkaline water bodies. With its high nutritional value, Spirulina has been consumed as food for centuries in Central Africa. It is now widely used as nutraceutical food supplement worldwide. Recently, great attention and extensive studies have been devoted to evaluate its therapeutic benefits on an array of diseased conditions including hypercholesterolemia, hyperglycerolemia, cardiovascular diseases, inflammatory diseases, cancer a...

  11. CO{sub 2} capture and biofuels production with microalgae

    Energy Technology Data Exchange (ETDEWEB)

    Benemann, J.R. [Univ. of California, Berkeley, CA (United States)

    1995-11-01

    Microalgae cultivation in large open ponds is the only biological process capable of directly utilizing power plant flue gas CO{sub 2} for production of renewable fuels, such as biodiesel, thus mitigating the potential for global warming. Past and recent systems studies have concluded that in principle this concept could be economically feasible, but that this technology still requires both fundamental and applied long-term R&D.

  12. Polishing of municipal secondary effluent using native microalgae consortia.

    Science.gov (United States)

    Beltrán-Rocha, Julio César; Barceló-Quintal, Icela Dagmar; García-Martínez, Magdalena; Osornio-Berthet, Luis; Saavedra-Villarreal, Nidia; Villarreal-Chiu, Juan; López-Chuken, Ulrico Javier

    2017-04-01

    This work evaluates the use of native microalgae consortia for a dual role: polishing treatment of municipal wastewater effluents and microalgae biomass feedstock potential for biodiesel or biofertilizer production. An initial screening was undertaken to test N and P removal from secondary effluents and biomass production by 12 consortia. A subsequent treatment was performed by selected consortia (01 and 12) under three operational conditions: stirring (S), S + 12 h of daily aeration (S + A) and S + A enriched with CO 2 (S + AC). All treatments resulted in compliance with environmental regulations (e.g. Directive 91/271/EEC) and high removal efficiency of nutrients: 64-79% and 80-94% of total N and PO 4 3- -P respectively. During the experiments it was shown that pH alkalinization due to microalgae growth benefits the chemical removal of ammonia and phosphorus. Moreover, advantages of pH increase could be accomplished by intermittent CO 2 addition which in this research (treatment S + AC) promoted higher yield and lipid concentration. The resulting dry biomass analysis showed a low lipid content (0.5-4.3%) not ideal for biodiesel production. Moreover, the high rate of ash (29.3-53.0%) suggests that biomass could be readily recycled as a biofertilizer due to mineral supply and organic constituents formed by C, N and P (e.g. carbohydrate, protein, and lipids).

  13. Developments and challenges in biodiesel production from microalgae: A review.

    Science.gov (United States)

    Taparia, Tanvi; Mvss, Manjari; Mehrotra, Rajesh; Shukla, Paritosh; Mehrotra, Sandhya

    2016-09-01

    The imminent depletion of fossil fuels and the surging global demand for renewable energy have led to the search for nonconventional energy sources. After a few decades of trial and error, the world is now testing the sources of the third generation of fossil fuels, which contain for most parts microalgae. With more than 80% oil content, being adaptable in growth parameters and highly versatile, microalgae are highly promising sources of biofuels in the present time. The present article makes a sweeping attempt to highlight the various methods employed for cultivation of microalgae, techniques to harvest and extract biomass from huge algal cultures, as well as their downstream production and processing procedures. The advantages, limitations, and challenges faced by each of them have been described to some extent. Major concerns pertaining to biofuels are supposed to be their environmental sustainability and economic viability along with their cost effectiveness. This would require a great deal of empirical data on existing systems and a great deal of optimization to generate a more robust one. We have concluded our article with a SWOT analysis of using algae for biodiesel production in a tabulated form. © 2015 International Union of Biochemistry and Molecular Biology, Inc.

  14. Algevir: An Expression System for Microalgae Based on Viral Vectors

    Science.gov (United States)

    Bañuelos-Hernández, Bernardo; Monreal-Escalante, Elizabeth; González-Ortega, Omar; Angulo, Carlos; Rosales-Mendoza, Sergio

    2017-01-01

    The use of recombinant algae for the production of valuable compounds is opening promising biotechnological applications. However, the development of efficient expression approaches is still needed to expand the exploitation of microalgae in biotechnology. Herein, the concept of using viral expression vectors in microalgae was explored for the first time. An inducible geminiviral vector leading to Rep-mediated replication of the expression cassette allowed the production of antigenic proteins at high levels. This system, called Algevir, allows the production of complex viral proteins (GP1 from Zaire ebolavirus) and bacterial toxin subunits (B subunit of the heat-labile Escherichia coli enterotoxin), which retained their antigenic activity. The highest achieved yield was 1.25 mg/g fresh biomass (6 mg/L of culture), which was attained 3 days after transformation. The Algevir system allows for a fast and efficient production of recombinant proteins, overcoming the difficulties imposed by the low yields and unstable expression patterns frequently observed in stably transformed microalgae at the nuclear level; as well as the toxicity of some target proteins. PMID:28713333

  15. Microalgae dewatering based on forward osmosis employing proton exchange membrane.

    Science.gov (United States)

    Son, Jieun; Sung, Mina; Ryu, Hoyoung; Oh, You-Kwan; Han, Jong-In

    2017-11-01

    In this study, electrically-facilitated forward osmosis (FO) employing proton exchange membrane (PEM) was established for the purpose of microalgae dewatering. An increase in water flux was observed when an external voltage was applied to the FO equipped with the PEM; as expected, the trend became more dramatic with both concentration of draw solution and applied voltage raised. With this FO used for microalgae dewatering, 247% of increase in flux and 86% in final biomass concentration were observed. In addition to the effect on flux improvement, the electrically-facilitated FO exhibited the ability to remove chlorophyll from the dewatered biomass, down to 0.021±0015mg/g cell. All these suggest that the newly suggested electrically-facilitated FO, one particularly employed PEM, can indeed offer a workable way of dewatering of microalgae; it appeared to be so because it can also remove the ever-problematic chlorophyll from extracted lipids in a simultaneous fashion. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Enzymatic cell disruption of microalgae biomass in biorefinery processes.

    Science.gov (United States)

    Demuez, Marie; Mahdy, Ahmed; Tomás-Pejó, Elia; González-Fernández, Cristina; Ballesteros, Mercedes

    2015-10-01

    When employing biotechnological processes for the procurement of biofuels and bio-products from microalgae, one of the most critical steps affecting economy and yields is the "cell disruption" stage. Currently, enzymatic cell disruption has delivered effective and cost competitive results when compared to mechanical and chemical cell disruption methods. However, the introduction of enzymes implies additional associated cost within the overall process. In order to reduce this cost, autolysis of microalgae is proposed as alternative enzymatic cell disruption method. This review aims to provide the state of the art of enzymatic cell disruption treatments employed in biorefinery processes and highlights the use of endopeptidases. During the enzymatic processes of microalgae life cycle, some lytic enzymes involved in cell division and programmed cell death have been proven useful in performing cell lysis. In this context, the role of endopeptidases is emphasized. Mirroring these natural events, an alternative cell disruption approach is proposed and described with the potential to induce the autolysis process using intrinsic cell enzymes. Integrating induced autolysis within biofuel production processes offers a promising approach to reduce overall global costs and energetic input associated with those of current cell disruption methods. A number of options for further inquiry are also discussed. © 2015 Wiley Periodicals, Inc.

  17. Innovative Alternative Technologies to Extract Carotenoids from Microalgae and Seaweeds

    Science.gov (United States)

    Poojary, Mahesha M.; Barba, Francisco J.; Aliakbarian, Bahar; Donsì, Francesco; Pataro, Gianpiero; Dias, Daniel A.; Juliano, Pablo

    2016-01-01

    Marine microalgae and seaweeds (microalgae) represent a sustainable source of various bioactive natural carotenoids, including β-carotene, lutein, astaxanthin, zeaxanthin, violaxanthin and fucoxanthin. Recently, the large-scale production of carotenoids from algal sources has gained significant interest with respect to commercial and industrial applications for health, nutrition, and cosmetic applications. Although conventional processing technologies, based on solvent extraction, offer a simple approach to isolating carotenoids, they suffer several, inherent limitations, including low efficiency (extraction yield), selectivity (purity), high solvent consumption, and long treatment times, which have led to advancements in the search for innovative extraction technologies. This comprehensive review summarizes the recent trends in the extraction of carotenoids from microalgae and seaweeds through the assistance of different innovative techniques, such as pulsed electric fields, liquid pressurization, supercritical fluids, subcritical fluids, microwaves, ultrasounds, and high-pressure homogenization. In particular, the review critically analyzes technologies, characteristics, advantages, and shortcomings of the different innovative processes, highlighting the differences in terms of yield, selectivity, and economic and environmental sustainability. PMID:27879659

  18. Innovative Alternative Technologies to Extract Carotenoids from Microalgae and Seaweeds

    Directory of Open Access Journals (Sweden)

    Mahesha M. Poojary

    2016-11-01

    Full Text Available Marine microalgae and seaweeds (microalgae represent a sustainable source of various bioactive natural carotenoids, including β-carotene, lutein, astaxanthin, zeaxanthin, violaxanthin and fucoxanthin. Recently, the large-scale production of carotenoids from algal sources has gained significant interest with respect to commercial and industrial applications for health, nutrition, and cosmetic applications. Although conventional processing technologies, based on solvent extraction, offer a simple approach to isolating carotenoids, they suffer several, inherent limitations, including low efficiency (extraction yield, selectivity (purity, high solvent consumption, and long treatment times, which have led to advancements in the search for innovative extraction technologies. This comprehensive review summarizes the recent trends in the extraction of carotenoids from microalgae and seaweeds through the assistance of different innovative techniques, such as pulsed electric fields, liquid pressurization, supercritical fluids, subcritical fluids, microwaves, ultrasounds, and high-pressure homogenization. In particular, the review critically analyzes technologies, characteristics, advantages, and shortcomings of the different innovative processes, highlighting the differences in terms of yield, selectivity, and economic and environmental sustainability.

  19. Utilization of organic residues using heterotrophic microalgae and insects.

    Science.gov (United States)

    Pleissner, Daniel; Rumpold, Birgit A

    2018-02-01

    Various organic residues occur globally in the form of straw, wood, green biomass, food waste, feces, manure etc. Other utilization strategies apart from anaerobic digestion, composting and incineration are needed to make use of the whole potential of organic residues as sources of various value added compounds. This review compares the cultivation of heterotrophic microalgae and insects using organic residues as nutrient sources and illuminates their potential with regard to biomass production, productivity and yield, and utilization strategies of produced biomasses. Furthermore, cultivation processes as well as advantages and disadvantages of utilization processes are identified and discussed. It was shown that both heterotrophic algae and insects are able to reduce a sufficient amount of organic residues by converting it into biomass. The biomass composition of both organisms is similar which allows similar utilization strategies in food and feed, chemicals and materials productions. Even though insect is the more complex organism, biomass production can be carried out using simple equipment without sterilization and hydrolysis of organic residues. Contrarily, heterotrophic microalgae require a pretreatment of organic residues in form of sterilization and in most cases hydrolysis. Interestingly, the volumetric productivity of insect biomass exceeds the productivity of algal biomass. Despite legal restrictions, it is expected that microalgae and insects will find application as alternative food and feed sources in the future. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Biodiesel production from microalgae: cultivation parameters that affect lipid production

    International Nuclear Information System (INIS)

    Arias Penaranda, Martha Trinidad; Martinez Roldan, Alfredo de Jesus; Canizares Villanueva, Rosa Olivia

    2013-01-01

    The microalgae have the capacity to mitigate CO 2 emissions and to produce lipids, which are considered with potential to obtain third-generation biofuel. This review provides updated information of the influence of culture conditions on the lipids production with high productivity and profile suitable for the biodiesel production. This document presents a compilation of research conclusions over the last 13 years around the world. in the literature consulted, the authors conclude that although the behavior of microalgae at physiological stress conditions, varies between species; the nutrients limitation, especially nitrogen and phosphorus, associated with heterotrophic growth or high irradiances in phototrophy are considered the most efficient strategies to increase the lipid content in microalgae, particularly triglycerides (consisting of saturated and monounsaturated fatty acids), which are excellent for the production of biodiesel. Also, it is reported that the lipid content increase and the number of unsaturated fatty acids decrease with the addition of small amounts of CO 2 and harvesting the biomass it the stationary phase of growth.

  1. Phenotypic screening with oleaginous microalgae reveals modulators of lipid productivity.

    Science.gov (United States)

    Franz, Annaliese K; Danielewicz, Megan A; Wong, Diana M; Anderson, Lisa A; Boothe, Jordan R

    2013-05-17

    Here we describe the first phenotypic screening with microalgae to study lipid metabolism and to discover organic small molecules as chemical triggers that increase growth and lipid production. A microplate assay has been developed for analysis of intracellular lipids using Nile Red fluorescence in order to screen a collection of diverse bioactive organic molecules (e.g., kinase inhibitors) with four strains of oleaginous microalgae (Nannochloropsis salina, Nannochloropsis oculata, Nannochloris sp., and Phaeodactylum tricornutum). Several small molecules identified in microplate screening increased lipid productivity >200% without decreasing growth and biomass production. Selected compounds were further investigated in the context of larger batch culture experiments (e.g., 500 mL) and demonstrated to increase lipid levels (up to 84%) while maintaining or increasing the specific growth rate. Bioactive molecules such as forskolin and quinacrine were identified as promising probes of microalgae lipid pathways. We have also determined that common antioxidants such as epigallocatechin gallate and butylated hydroxyanisole (BHA) increase lipid productivity and may represent new probes of oxidative signaling pathways for photooxidative protection.

  2. Engineering the Chloroplast Genome of Oleaginous Marine Microalga Nannochloropsis oceanica

    Directory of Open Access Journals (Sweden)

    Qinhua Gan

    2018-04-01

    Full Text Available Plastid engineering offers an important tool to fill the gap between the technical and the enormous potential of microalgal photosynthetic cell factory. However, to date, few reports on plastid engineering in industrial microalgae have been documented. This is largely due to the small cell sizes and complex cell-wall structures which make these species intractable to current plastid transformation methods (i.e., biolistic transformation and polyethylene glycol-mediated transformation. Here, employing the industrial oleaginous microalga Nannochloropsis oceanica as a model, an electroporation-mediated chloroplast transformation approach was established. Fluorescent microscopy and laser confocal scanning microscopy confirmed the expression of the green fluorescence protein, driven by the endogenous plastid promoter and terminator. Zeocin-resistance selection led to an acquisition of homoplasmic strains of which a stable and site-specific recombination within the chloroplast genome was revealed by sequencing and DNA gel blotting. This demonstration of electroporation-mediated chloroplast transformation opens many doors for plastid genome editing in industrial microalgae, particularly species of which the chloroplasts are recalcitrant to chemical and microparticle bombardment transformation.

  3. Algevir: An Expression System for Microalgae Based on Viral Vectors

    Directory of Open Access Journals (Sweden)

    Bernardo Bañuelos-Hernández

    2017-06-01

    Full Text Available The use of recombinant algae for the production of valuable compounds is opening promising biotechnological applications. However, the development of efficient expression approaches is still needed to expand the exploitation of microalgae in biotechnology. Herein, the concept of using viral expression vectors in microalgae was explored for the first time. An inducible geminiviral vector leading to Rep-mediated replication of the expression cassette allowed the production of antigenic proteins at high levels. This system, called Algevir, allows the production of complex viral proteins (GP1 from Zaire ebolavirus and bacterial toxin subunits (B subunit of the heat-labile Escherichia coli enterotoxin, which retained their antigenic activity. The highest achieved yield was 1.25 mg/g fresh biomass (6 mg/L of culture, which was attained 3 days after transformation. The Algevir system allows for a fast and efficient production of recombinant proteins, overcoming the difficulties imposed by the low yields and unstable expression patterns frequently observed in stably transformed microalgae at the nuclear level; as well as the toxicity of some target proteins.

  4. Potential carbon dioxide fixation by industrially important microalgae.

    Science.gov (United States)

    Sydney, Eduardo Bittencourt; Sturm, Wilerson; de Carvalho, Julio Cesar; Thomaz-Soccol, Vanete; Larroche, Christian; Pandey, Ashok; Soccol, Carlos Ricardo

    2010-08-01

    The present study aimed at investigating the carbon metabolism in terms of carbon dioxide fixation and its destination in microalgae cultivations. To this purpose, analysis of growth parameters, media of cultivation, biomass composition and productivity and nutrients balance were performed. Four microalgae suitable for mass cultivation were evaluated: Dunaliella tertiolecta SAD-13.86, Chlorella vulgaris LEB-104, Spirulina platensis LEB-52 and Botryococcus braunii SAG-30.81. Global rates of carbon dioxide and oxygen were determinated by a system developed in our laboratory. B. braunii presented the highest CO(2) fixation rate, followed by S. platensis,D. tertiolecta and C. vulgaris (496.98, 318.61, 272.4 and 251.64 mg L(-1)day(-1), respectively). Carbon dioxide fixated was mainly used for microalgal biomass production. Nitrogen, phosphorus (calcium for D. tertiolecta), potassium and magnesium consumption rates (mg gX(-1)) were evaluated for the four microalgae. Biomass composition presented a predominance of proteins but also a high amount of lipids, especially in D. tertiolecta and B. braunii. (c) 2010. Published by Elsevier Ltd.

  5. Effect of coagulant/flocculants on bioproducts from microalgae.

    Science.gov (United States)

    Anthony, Renil J; Ellis, Joshua T; Sathish, Ashik; Rahman, Asif; Miller, Charles D; Sims, Ronald C

    2013-12-01

    The potential of microalgae as a source of sustainable energy, nutritional supplements and specialized chemicals necessitates a thorough evaluation of the methods of harvesting microalgae with regards to the bioproduct(s) desired. This research assessed the effect of coagulation, flocculation, and centrifugation on the wet lipid extraction procedure, which fractionated microalgae into hydrolyzed biomass for fermentation into acetone, butanol, and ethanol, an aqueous phase as growth media for genetically engineered Escherichia coli, and a lipid fraction for the production of biodiesel. Biomass harvested by cationic starches, alum, and centrifugation produced 30, 19, and 22.5mg/g of dry wt. algae of total combined acetone, butanol, and ethanol, respectively. Higher biodiesel production was also observed for the cationic starches (9.6 mg/g of dry wt. algae) than alum (0.6 mg/g of dry wt. algae) harvested biomass. The results suggested significant effect of the harvesting methods on the yields of bioproducts. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. Innovative Alternative Technologies to Extract Carotenoids from Microalgae and Seaweeds.

    Science.gov (United States)

    Poojary, Mahesha M; Barba, Francisco J; Aliakbarian, Bahar; Donsì, Francesco; Pataro, Gianpiero; Dias, Daniel A; Juliano, Pablo

    2016-11-22

    Marine microalgae and seaweeds (microalgae) represent a sustainable source of various bioactive natural carotenoids, including β-carotene, lutein, astaxanthin, zeaxanthin, violaxanthin and fucoxanthin. Recently, the large-scale production of carotenoids from algal sources has gained significant interest with respect to commercial and industrial applications for health, nutrition, and cosmetic applications. Although conventional processing technologies, based on solvent extraction, offer a simple approach to isolating carotenoids, they suffer several, inherent limitations, including low efficiency (extraction yield), selectivity (purity), high solvent consumption, and long treatment times, which have led to advancements in the search for innovative extraction technologies. This comprehensive review summarizes the recent trends in the extraction of carotenoids from microalgae and seaweeds through the assistance of different innovative techniques, such as pulsed electric fields, liquid pressurization, supercritical fluids, subcritical fluids, microwaves, ultrasounds, and high-pressure homogenization. In particular, the review critically analyzes technologies, characteristics, advantages, and shortcomings of the different innovative processes, highlighting the differences in terms of yield, selectivity, and economic and environmental sustainability.

  7. Stabilisation of microalgae: Iodine mobilisation under aerobic and anaerobic conditions.

    Science.gov (United States)

    Han, Wei; Clarke, William; Pratt, Steven

    2015-10-01

    Mobilisation of iodine during microalgae stabilisation was investigated, with the view of assessing the potential of stabilised microalgae as an iodine-rich fertiliser. An iodine-rich waste microalgae (0.35 ± 0.05 mg I g(-1) VS(added)) was stabilised under aerobic and anaerobic conditions. Iodine mobilisation was linearly correlated with carbon emission, indicating iodine was in the form of organoiodine. Comparison between iodine and nitrogen mobilisation relative to carbon emission indicated that these elements were, at least in part, housed separately within the cells. After stabilisation, there were 0.22 ± 0.05 and 0.19 ± 0.01 mg g(-1) VS(added) iodine remaining in the solid in the aerobic and anaerobic processed material respectively, meaning 38 ± 5.0% (aerobic) and 50 ± 8.6% (anaerobic) of the iodine were mobilised, and consequently lost from the material. The iodine content of the stabilised material is comparable to the iodine content of some seaweed fertilisers, and potentially satisfies an efficient I-fertilisation dose. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Biodiesel renovável derivado de microalgas: avanços e perspectivas tecnológicas

    Directory of Open Access Journals (Sweden)

    Claudio M. P. Pereira

    2012-01-01

    Full Text Available Microalgae are a promising source of raw material for biodiesel production. This review discusses the latest developments related to the application of microalgae biomass for biodiesel production. Characterization of fatty acid of microalgae and comparisons with other sources of raw materials and processes are presented. Furthermore, technological perspectives and approaches for growing microalgae in photobioreactors, microalgal oil extraction techniques, and procedures for synthesizing biodiesel are reviewed.

  9. Mecanismos de resistencia a Metales tóxicos (CD bajo variaciones abióticas en Microalgas

    Directory of Open Access Journals (Sweden)

    Alondra A. Cortés Téllez

    2018-01-01

    Full Text Available En los ecosistemas acuáticos, la presencia de ciertos metales (Cu, Zn, Fe a concentraciones traza son esencialespara distintas actividades biológicas. Sin embargo, otros metales como el Cd y Pb son considerados tóxicos aconcentraciones muy bajas y no participan como micronutrientes. Estos metales interactúan con componentesesenciales a través de enlaces iónicos y covalentes induciendoestrés oxidativo, reemplazo de cationes esenciales,etc. Asimismo, presentan la capacidad de acumularse y biomagnificarse a lo largo de la cadena trófica, promoviendoalta sensibilidad en la mayoría de los organismos acuáticos, mientras que otros como las microalgas, han desarrolladouna gran variedad de estrategias de detoxificación para minimizar los efectos tóxicos de losmetales a través de lainducción de mecanismos de adaptación y resistencia que les permiten la supervivencia a esos ambientes extremos.Por ende, es indispensable conocer la gama de mecanismos de resistencia que estos organismos presentan a laexposición de metales tóxicos presentes en el ecosistema acuático. Así, los objetivos de esta revisión son: identificary describir los principales mecanismos moleculares actualmente descritos en microalgas verdes implicados en laresistencia a metales tóxicos en relación específica con el cadmio; dar a conocer la influencia de distintos factoresambientales sobre esta respuesta y los episodios de corresistencia hacia otros metales de carácter tóxico.

  10. Suplementación con harina de banano sobre la ganancia de peso en novillas Jersey

    Directory of Open Access Journals (Sweden)

    Claudio Fabi\\u00E1n Vargas-Rodr\\u00EDguez

    2007-01-01

    Full Text Available Suplementación con harina de banano sobre la ganancia de peso en novillas Jersey. El experimento se realizó entre los meses de febrero y mayo del año 2005, en la Estación Experimental Alfredo Volio Mata de la Universidad de Costa Rica, con la intención de probar la harina de banano como fuente alternativa de energía en la alimentación de novillas Jersey en desarrollo. Se estimó la ganancia de peso de 15 animales mediante la metodología de cuadrados latinos repetidos (cinco grupos asignados de acuerdo a su peso corporal, los cuales fueron alimentados con dietas que contenían tres niveles de harina de banano (0,00%, 0,33% y 0,66% de Peso Vivo. Los mejores resultados se obtuvieron con el nivel de inclusión intermedio (0,33% y se estimó que al agregar dosis mayores a 0,36% PV disminuye la ganancia de peso por día, lo que no justifica la suplementación más allá de ese punto.

  11. PRODUCCIÓN DE BIODIESEL A PARTIR DE MICROALGAS: PARÁMETROS DEL CULTIVO QUE AFECTAN LA PRODUCCIÓN DE LÍPIDOS

    Directory of Open Access Journals (Sweden)

    Martha Trinidad Arias Peñaranda

    2013-01-01

    Full Text Available Las microalgas poseen la capacidad para mitigar las emisiones de CO2  y producir lípidos, por lo que se consideran con potencial para la obtención de biocombustibles de tercera generación. La presente revisión proporciona información actualizada de la influencia de las condiciones de cultivo, sobre la obtención de lípidos con una productividad elevada y perfil adecuado para la producción de biodiesel, se proporciona una síntesis de resultados de investigaciones realizadas en los últimos 13 años en diversas partes del mundo. En la literatura consultada, los autores concluyen que aunque el comportamiento de las microalgas ante condiciones de estrés fisiológico es variable entre especies; la limitación de nutrientes especialmente nitrógeno y fósforo, asociado al crecimiento heterotrófico o a altas intensidades luminosas en fototrofía se consideran como las estrategias más eficientes para incrementar el contenido de lípidos en las microalgas, en particular de triglicéridos constituidos por ácidos grasos saturados y monoinsaturados, ideales para la producción de biodiesel. De igual forma, señalan que la presencia de pequeñas cantidades de CO2  y la cosecha de la biomasa en la fase estacionaria de crecimiento, incrementan el contenido de lípidos y disminuyen el número de insaturaciones de los ácidos grasos que lo conforman.

  12. Screening of microalgae for integral biogas slurry nutrient removal and biogas upgrading by different microalgae cultivation technology.

    Science.gov (United States)

    Wang, Xue; Bao, Keting; Cao, Weixing; Zhao, Yongjun; Hu, Chang Wei

    2017-07-14

    The microalgae-based technology has been developed to reduce biogas slurry nutrients and upgrade biogas simultaneously. In this work, five microalgal strains named Chlorella vulgaris, Scenedesmus obliquus, Selenastrum capricornutum, Nitzschia palea, and Anabaena spiroides under mono- and co-cultivation were used for biogas upgrading. Optimum biogas slurry nutrient reduction could be achieved by co-cultivating microalgae (Chlorella vulgaris, Scenedesmus obliquus, and Nitzschia palea) with fungi using the pelletization technology. In addition, the effects of different ratio of mixed LED light wavelengths applying mixed light-emitting diode during algae strains and fungi co-cultivation on CO 2 and biogas slurry nutrient removal efficiency were also investigated. The results showed that the COD (chemical oxygen demand), TN (total nitrogen), and TP (total phosphorus) removal efficiency were 85.82 ± 5.37%, 83.31 ± 4.72%, and 84.26 ± 5.58%, respectively at red: blue = 5:5 under the co-cultivation of S. obliquus and fungi. In terms of biogas upgrading, CH 4 contents were higher than 90% (v/v) for all strains, except the co-cultivation with S. obliquus and fungi at red: blue = 3:7. The results indicated that co-cultivation of microalgae with fungi under mixed light wavelengths treatments was most successful in nutrient removal from wastewater and biogas upgrading.

  13. Histologia do fígado de tilápia do Nilo ( Oreochromis niloticus alimentados com dietas contendo silagem biológica de pescado

    Directory of Open Access Journals (Sweden)

    Claucia A. Honorato

    2014-12-01

    Full Text Available Resumo: Este estudo teve como objetivo avaliar as possíveis alterações histopatológicas hepática de tilápias do Nilo alimentadas com dietas contendo silagem biológica de pescado com diferentes concentrações protéicas. Foram utilizados 180 juvenis alimentados com dietas contendo três níveis de proteína (20, 24 and 28% PB, e duas proporções de silagem biológica (¼ e ½ durante 75 dias. Os fragementos de fígado foram fixados em Bouin e inclusos em Histosec®. Posteriorente foram cortados em microtomo com espessura de 2 a 5μm. O método utilizado para coloração foi hematoxilina/eosina e PAS. Os cortes histológicos foram analisados em microscopio de luz. O desarranjo na morfologia do fígado dos peixes alimentados com silagem biológica foi influenciado pelos altos níveis protéicos, e pelo aumento ½ de proporções de proteínas de origem animal das dietas. Foi observado que a variação dos hepatócitos está diretamente ligada com o tipo da dieta fornecida para os peixes. Nos peixes alimentados com as dietas contendo 28% PB, o fígado apresentou desarranjo da estrutura cordonal dos hepatócitos, pontos de necrose e deslocamento do núcleo para periferia. Níveis elevados de silagem biológica de pescado provoca alterações deletérias no fígado. O nível de proteína adequado para manter o desenvolvimento associado à saúde do peixe é de 24%PB.

  14. Microalgae Production Cost Analysis: Development of Goals And Its Implications On Future Research

    Energy Technology Data Exchange (ETDEWEB)

    Hill, A. M.; McIntosh, R. P.

    1984-01-17

    This paper presents an overview of the production and economic models, with specific discussion of input assumptions used to derive microalgae product costs for the state of the art, theoretical-best and for the 1994 attainability target. These product cost estimates form the basis for developing program cost goals for microalgae fuel technology.

  15. Lipid-based liquid biofuels from autotrophic microalgae: energetic and environmental performance

    NARCIS (Netherlands)

    Reijnders, L.

    2013-01-01

    Commercial cultivation of autotrophic microalgae for food production dates back to the 1950s. Autotrophic microalgae have also been proposed as a source for lipid-based liquid biofuels. As yet, there is no commercial production of such biofuels and estimated near-term prices are far in excess of

  16. Inventory of Sources of Available Saline Waters for Microalgae Mass Culture in the State of Arizona

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, L. G.; Olson, K. L.; Wallace, M. G.; Osborn, M. D.

    1986-06-25

    The Solar Energy Research Institute (SERI) is conducting research on the development of microalgae biomass systems for the production of liquid fuels. Particularly appealing at this time, is the idea of using indigenous resources of the Southwest for large-scale production of microalgae.

  17. Techno-economic assessment of micro-algae as feedstock for renewable bio-energy production

    NARCIS (Netherlands)

    Jonker, J.G.G.; Faaij, A.P.C.

    2013-01-01

    This paper determines the energy consumption ratio and overall bio-energy production costs of microalgae cultivation, harvesting and conversion to secondary energy carriers, thus helping to clarify future perspectives of micro-algae production for energy purposes. A limitation growth model is

  18. Effective harvesting of the microalgae Chlorella protothecoides via bioflocculation with cationic starch

    DEFF Research Database (Denmark)

    Letelier Gordo, Carlos Octavio; Holdt, Susan Løvstad; De Francisci, Davide

    2014-01-01

    In the present work, the flocculation efficiency of cationic starch (Greenfloc 120) was tested on the fresh water microalga Chlorella protothecoides under different conditions (pH and flocculant concentrations). Different concentrations of Greenfloc 120 (0, 2.5, 5, 10, 20, 40mgL-1) were screened...... to use, efficient and cost-effective flocculant for harvesting of microalgae....

  19. Flotation: A promising microalgae harvesting and dewatering technology for biofuels production.

    Science.gov (United States)

    Ndikubwimana, Theoneste; Chang, Jingyu; Xiao, Zongyuan; Shao, Wenyao; Zeng, Xianhai; Ng, I-Son; Lu, Yinghua

    2016-03-01

    Microalgal biomass as renewable energy source is believed to be of great potential for reliable and sustainable biofuels production. However, microalgal biomass production is pinned by harvesting and dewatering stage thus hindering the developing and growing microalgae biotechnology industries. Flotation technology applied in mineral industry could be potentially applied in microalgae harvesting and dewatering, however substantial knowledge on different flotation units is essential. This paper presents an overview on different flotation units as promising cost-effective technologies for microalgae harvesting thus bestowing for further research in development and commercialization of microalgae based biofuels. Dispersed air flotation was found to be less energy consuming. Moreover, Jameson cell flotation and dispersed ozone flotation are believed to be energy efficient microalgae flotation approaches. Microalgae harvesting and dewatering by flotation is still at embryonic stage, therefore extended studies with the focus on life cycle assessment, sustainability of the flotation unit, optimization of the operating parameters using different algal species is imperative. Though there are a number of challenges in microalgae harvesting and dewatering, with well designed and developed cultivation, harvesting/dewatering, extraction and conversion technologies, progressively, microalgae technology will be of great potential for biological carbon sequestration, biofuels and biochemicals production. Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Interactions of microalgae and other microorganisms for enhanced production of high-value compounds.

    Science.gov (United States)

    Lutzu, Giovanni Antonio; Turgut Dunford, Nurhan

    2018-03-01

    The cultivation of microalgae for the production of biomass and associated valuable compounds has gained increasing interest not only within the scientific community but also at the industrial level. Microalgae cells are capable of producing high-value compounds that are widely used in food, feed, pharmaceutical, medical, nutraceutical, cosmeceutical, and aquaculture industries. For example, lipids produced by algae can be converted to biodiesel, other fuels and bio-products. Hence, high oil content algal biomass has been regarded as a potential alternative feedstock to replace terrestrial crops for sustainable production of bio-products. It has been reported that the interaction of microalgae and other microorganisms greatly enhances the efficiency of microalgal biomass production and its chemical composition. Microalgae-bacteria interaction with an emphasis on the nature of symbiotic relationship in mutualisitc and parasitic consortia has been extensively studied. For instance, it is well documented that production of vitamins or growth promoting factors by bacteria enhances the growth of microalgae. Little attention has been paid to the consortia formed by microalgae and other microorganisms such as other microalgae strains, cyanobacteria, fungi, and yeasts. Hence, the aim of this review is to investigate the impact of the microalgae-other microorganism interactions on the production of high value compounds.

  1. Milking of microalgae: Production and selective extraction of Beta-carotene in two-phase bioreactors

    NARCIS (Netherlands)

    Hejazi, M.

    2003-01-01

    The low productivity of photobioreactors used for production of high-value compounds from microalgae is a big bottleneck in commercialization. "Milking" of microalgae for the production of high-value compounds in which the produced biomass is reused for production can be a solution to overcome

  2. Modeling the competition between antenna size mutant and wild type microalgae in outdoor mass culture

    NARCIS (Netherlands)

    Mooij, de Tim; Schediwy, Kira; Wijffels, René H.; Janssen, Marcel

    2016-01-01

    Under high light conditions, microalgae are oversaturated with light which significantly reduces the light use efficiency. Microalgae with a reduced pigment content, antenna size mutants, have been proposed as a potential solution to increase the light use efficiency. The goal of this study was

  3. Sorting cells of the microalga Chlorococcum littorale with increased triacylglycerol productivity

    NARCIS (Netherlands)

    Dominguez Teles, I.; Zwart, van der Mathijs; Kleinegris, D.M.M.; Wijffels, R.H.; Barbosa, M.J.

    2016-01-01

    Despite extensive research in the last decades, microalgae are still only economically feasible for high valued markets. Strain improvement is a strategy to increase productivities, hence reducing costs. In this work, we focus on microalgae selection: taking advantage of the natural biological

  4. Lipid-Derived Biofuels: Determination of Factors that Control Triglyceride Accumulation in Microalgae

    Science.gov (United States)

    2012-10-30

    Accumulation in Microalgae Principal Investigator Dr. K.E. Cooksey Department of Microbiology 109 Lewis Hall Montana State University...neutral lipid generation for biofuel production through an examination of the biochemical and molecular processes important in the accumulation of...cultures to find the extent to which previously published results can be considered general for microalgae . Task 2. Quantify growth kinetics and

  5. Milking of microalgae: Production and selective extraction of Beta-carotene in two-phase bioreactors

    NARCIS (Netherlands)

    Hejazi, M.

    2003-01-01

    The low productivity of photobioreactors used for production of high-value compounds from microalgae is a big bottleneck in commercialization. "Milking" of microalgae for the production of high-value compounds in which the produced biomass is reused for production can be a

  6. Cultivation of microalgae: effect of light/dark cycles on biomass yield

    NARCIS (Netherlands)

    Janssen, M.G.J.

    2002-01-01

    In this thesis the efficiency of light utilization of microalgae was studied under light/dark cycles encountered in photobioreactors. Phototrophic microorganisms such as microalgae and cyanobacteria could provide valuable compounds. For many of these applications it is essential to use

  7. Nota científica: perfil bioquímico de ratos alimentados com iogurte contendo extrato de erva-mate (Ilex paraguariensis St. Hil)

    OpenAIRE

    Ril,Franciele Taís; Loch,Camila Ronsoni; Valduga,Alice Teresa; Macedo,Sandra Manoela Dias; Cichoski,Alexandre José

    2011-01-01

    Este estudo teve como objetivo avaliar o efeito do iogurte contendo extrato de erva-mate (Ilex paraguariensis) e com/sem culturas probióticas sobre o perfil lipídico, glicêmico, hepático e renal de ratos alimentados com esses tipos de iogurtes. Ratos da linhagem Wistar (42) foram divididos em três grupos (n=14), e receberam iogurte sem extrato de erva-mate, iogurte com extrato de erva-mate 0,1% e iogurte com extrato de erva-mate 0,1% e culturas probióticas, durante 30 dias. Não foi observado ...

  8. Desempenho de frangos de corte alimentados com altos valores de balanço eletrolítico em região de clima quente

    OpenAIRE

    Vieites,F.M.; Fraga,A.L.; Souza,C.S.; Araújo,G.M.; Vargas Júnior,J.G.; Nunes,R.V.; Corrêa,G.S.S.

    2011-01-01

    Determinaram-se os melhores valores de balanço eletrolítico (BE) para o desempenho de frangos de corte de um a sete, um a 14, um a 21 e um a 42 dias de idade. Utilizaram-se 720 pintos comerciais, machos, criados em galpão de alvenaria, em boxes cobertos com maravalha, alimentados com dieta basal composta por milho e farelo de soja combinada com valores de BE de 200; 250; 300; 350 e 400mEq/kg. Adotou-se o delineamento inteiramente ao acaso, com seis repetições de 24 aves para cada uma das 30 u...

  9. Caracterización de corrientes de rodamientos en motores de inducción de Jaula de Ardilla alimentados por variadores de velocidad

    OpenAIRE

    Mejia Lopez, William

    2015-01-01

    El presente documento describe la caracterización de corrientes de rodamientos en motores de inducción de Jaula de Ardilla alimentados por variadores de velocidad. Se identifican las diferentes corrientes de rodamiento por medio de pruebas experimentales de medición de corrientes y voltajes en los rodamientos para motores de inducción de baja potencia. Se establece un modelo del motor de inducción para simulación de las corrientes de rodamiento por medio del método de elementos finitos y un m...

  10. Advances in Microalgae-Derived Phytosterols for Functional Food and Pharmaceutical Applications

    Science.gov (United States)

    Luo, Xuan; Su, Peng; Zhang, Wei

    2015-01-01

    Microalgae contain a variety of bioactive lipids with potential applications in aquaculture feed, biofuel, food and pharmaceutical industries. While microalgae-derived polyunsaturated fatty acid (PUFA) and their roles in promoting human health have been extensively studied, other lipid types from this resource, such as phytosterols, have been poorly explored. Phytosterols have been used as additives in many food products such as spread, dairy products and salad dressing. This review focuses on the recent advances in microalgae-derived phytosterols with functional bioactivities and their potential applications in functional food and pharmaceutical industries. It highlights the importance of microalgae-derived lipids other than PUFA for the development of an advanced microalgae industry. PMID:26184233

  11. Effect of Lignocellulose Related Compounds on Microalgae Growth and Product Biosynthesis: A Review

    Directory of Open Access Journals (Sweden)

    Krystian Miazek

    2014-07-01

    Full Text Available Microalgae contain valuable compounds that can be harnessed for industrial applications. Lignocellulose biomass is a plant material containing in abundance organic substances such as carbohydrates, phenolics, organic acids and other secondary compounds. As growth of microalgae on organic substances was confirmed during heterotrophic and mixotrophic cultivation, lignocellulose derived compounds can become a feedstock to cultivate microalgae and produce target compounds. In this review, different treatment methods to hydrolyse lignocellulose into organic substrates are presented first. Secondly, the effect of lignocellulosic hydrolysates, organic substances typically present in lignocellulosic hydrolysates, as well as minor co-products, on growth and accumulation of target compounds in microalgae cultures is described. Finally, the possibilities of using lignocellulose hydrolysates as a common feedstock for microalgae cultures are evaluated.

  12. Advances in Microalgae-Derived Phytosterols for Functional Food and Pharmaceutical Applications

    Directory of Open Access Journals (Sweden)

    Xuan Luo

    2015-07-01

    Full Text Available Microalgae contain a variety of bioactive lipids with potential applications in aquaculture feed, biofuel, food and pharmaceutical industries. While microalgae-derived polyunsaturated fatty acid (PUFA and their roles in promoting human health have been extensively studied, other lipid types from this resource, such as phytosterols, have been poorly explored. Phytosterols have been used as additives in many food products such as spread, dairy products and salad dressing. This review focuses on the recent advances in microalgae-derived phytosterols with functional bioactivities and their potential applications in functional food and pharmaceutical industries. It highlights the importance of microalgae-derived lipids other than PUFA for the development of an advanced microalgae industry.

  13. The role of biochemical engineering in the production of biofuels from microalgae.

    Science.gov (United States)

    Costa, Jorge Alberto Vieira; de Morais, Michele Greque

    2011-01-01

    Environmental changes that have occurred due to the use of fossil fuels have driven the search for alternative sources that have a lower environmental impact. First-generation biofuels were derived from crops such as sugar cane, corn and soybean, which contribute to water scarcity and deforestation. Second-generation biofuels originated from lignocellulose agriculture and forest residues, however these needed large areas of land that could be used for food production. Based on technology projections, the third generation of biofuels will be derived from microalgae. Microalgae are considered to be an alternative energy source without the drawbacks of the first- and second-generation biofuels. Depending upon the growing conditions, microalgae can produce biocompounds that are easily converted into biofuels. The biofuels from microalgae are an alternative that can keep the development of human activity in harmony with the environment. This study aimed to present the main biofuels that can be derived from microalgae. Copyright © 2010 Elsevier Ltd. All rights reserved.

  14. Intensification of microalgae drying and oil extraction process by vapor recompression and heat integration.

    Science.gov (United States)

    Song, Chunfeng; Liu, Qingling; Ji, Na; Deng, Shuai; Zhao, Jun; Kitamura, Yutaka

    2016-05-01

    Reducing energy penalty caused by drying and oil extraction is the most critical challenge in microalgae biodiesel production. In this study, vapor recompression and heat integration are utilized to optimize the performance of wet microalgae drying and oil extraction. In the microalgae drying stage, the hot exhaust stream is recompressed and coupled with wet microalgae to recover the condensate heat. In the oil extraction stage, the exergy rate of recovered solvent is also elevated by compressor and then exchanged heat with feed and bottom stream in the distillation column. Energy and mass balance of the intensified process is investigated and compared with the conventional microalgae drying-extraction process. The simulation results indicated that the total energy consumption of the intensified process can be saved by 52.4% of the conventional route. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Development of microalgae biomaterials with enhanced antioxidant activity using electron beam

    International Nuclear Information System (INIS)

    Kim, Younghwa; Park, Hyunjin; Choi, Soojeong; Lee, Jaehwa

    2013-01-01

    By increasing the antioxidant products (e. g. antioxidant enzyme, carotenoid, phycobiliproteins, chlorophyll, lipid phenolic compounds, etc.) in microalgae, it could be useful for industry. In this study, mutants of fresh water microalgae Arthrospira platensis (A. platensis) by high energy electron beam were isolated and characterized. Those selected mutants showed higher growth rate than parental strain. The antioxidant enzyme activity (SOD and POD), flavonoid, phenolic compound and phycocyanin of mutants were increased about 2 times compared to wild type. Moreover, DPPH radical scavenging activity was increased about 20%. Microalgae species with improved growth rate and enhanced active compounds make the commercial process more feasible in industry. Using microalgae mutants with increased antioxidant products, it is useful to develop microalgae biomaterials for neutraceuticals

  16. Enhancement of growth and lipid production from microalgae using fluorescent paint under the solar radiation.

    Science.gov (United States)

    Seo, Yeong Hwan; Cho, Changsoon; Lee, Jung-Yong; Han, Jong-In

    2014-12-01

    Solar radiation has intensity that is too high to inhibit microalgae activity and is composed of wide light spectrum including ultraviolet (UV) range which cannot be utilized for microalgae. For these reasons, the modification of solar radiation is required for effective microalgae cultivation, and to do that, fluorescent paint was used for not only blocking excessive solar energy but also converting UV to visible light. With fluorescent aqueous layer, microalgae was protected from photoinhibition and could grow well, but there was difference in growth and lipid accumulation efficiencies depending on the color; maximum dry weight of 1.7 g/L was achieved in red paint, whereas best lipid content of 30% was obtained in blue one. This phenomenon was due to the different light spectrum made by colors. With simple process using fluorescent paint, modification of light was successfully done and allowing microalgae to grow under strong radiation such as solar radiation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Development of microalgae biomaterials with enhanced antioxidant activity using electron beam

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Younghwa; Park, Hyunjin; Choi, Soojeong; Lee, Jaehwa [Silla Univ., Busan (Korea, Republic of)

    2013-07-01

    By increasing the antioxidant products (e. g. antioxidant enzyme, carotenoid, phycobiliproteins, chlorophyll, lipid phenolic compounds, etc.) in microalgae, it could be useful for industry. In this study, mutants of fresh water microalgae Arthrospira platensis (A. platensis) by high energy electron beam were isolated and characterized. Those selected mutants showed higher growth rate than parental strain. The antioxidant enzyme activity (SOD and POD), flavonoid, phenolic compound and phycocyanin of mutants were increased about 2 times compared to wild type. Moreover, DPPH radical scavenging activity was increased about 20%. Microalgae species with improved growth rate and enhanced active compounds make the commercial process more feasible in industry. Using microalgae mutants with increased antioxidant products, it is useful to develop microalgae biomaterials for neutraceuticals.

  18. Linking microalgae and cyanobacteria culture conditions and key-enzymes for carbohydrate accumulation.

    Science.gov (United States)

    González-Fernández, Cristina; Ballesteros, Mercedes

    2012-01-01

    Microalgae are regarded as a potential biomass source for biofuel purposes. With regard to bioethanol production, microalgae seem to overcome traditional substrate drawbacks. Enzymatic activities are responsible for carbon allocation and hence for carbohydrate profiles. Enzyme activities may be manipulated by metabolic engineering; however, this goal may also be achieved by controlling environmental conditions of the culture system. We outline the key-enzymes as well as the main operational conditions applied to microalgae growth (inorganic nutrient supplementation, irradiance and temperature) that affect carbohydrate synthesis on microalgae and cyanobacteria. Normally, harsh conditions are needed for such a goal and thus, arrested microalgae growth may occur. Potential strategies to avoid arrested growth, while enhancing carbohydrate accumulation, were also pointed out in this review. Copyright © 2012 Elsevier Inc. All rights reserved.

  19. Anaerobic digestion of microalgae residues resulting from the biodiesel production process

    International Nuclear Information System (INIS)

    Ehimen, E.A.; Sun, Z.F.; Carrington, C.G.; Birch, E.J.; Eaton-Rye, J.J.

    2011-01-01

    The recovery of methane from post transesterified microalgae residues has the potential to improve the renewability of the 'microalgae biomass to biodiesel' conversion process as well as reduce its cost and environmental impact. This paper deals with the anaerobic digestion of microalgae biomass residues (post transesterification) using semi-continuously fed reactors. The influence of substrate loading concentrations and hydraulic retention times on the specific methane yield of the anaerobically digested microalgae residues was investigated. The co-digestion of the microalgae residues with glycerol as well as the influence of temperature was also examined. It was found that the hydraulic retention period was the most significant variable affecting methane production from the residues, with periods (>5 days) corresponding to higher energy recovery. The methane yield was also improved by a reduction in the substrate loading rates, with an optimum substrate carbon to nitrogen ratio of 12.44 seen to be required for the digestion process.

  20. Flocculation properties of several microalgae and a cyanobacterium species during ferric chloride, chitosan and alkaline flocculation.

    Science.gov (United States)

    Lama, Sanjaya; Muylaert, Koenraad; Karki, Tika Bahadur; Foubert, Imogen; Henderson, Rita K; Vandamme, Dries

    2016-11-01

    Flocculation holds great potential as a low-cost harvesting method for microalgae biomass production. Three flocculation methods (ferric chloride, chitosan, and alkaline flocculation) were compared in this study for the harvesting of 9 different freshwater and marine microalgae and one cyanobacterium species. Ferric chloride resulted in a separation efficiency greater than 90% with a concentration factor (CF) higher than 10 for all species. Chitosan flocculation worked generally very well for freshwater microalgae, but not for marine species. Alkaline flocculation was most efficient for harvesting of Nannochloropsis, Chlamydomonas and Chlorella sp. The concentration factor was highly variable between microalgae species. Generally, minimum flocculant dosages were highly variable across species, which shows that flocculation may be a good harvesting method for some species but not for others. This study shows that microalgae and cyanobacteria species should not be selected solely based on their productivity but also on their potential for low-cost separation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Impacto del CO2 sobre la densidad celular en seis cepas de microalgas marinas

    Directory of Open Access Journals (Sweden)

    Alberto I. Oscanoa Huaynate

    2015-12-01

    Full Text Available Debido a la gran facilidad con que las microalgas pueden capturar el CO2 del medio ambiente, resulta interesante evaluar la cantidad y tiempo de ingreso de éste a los cultivos masivos, con la fi nalidad de aumentar la densidad celular. El objetivo del presente estudio fue evaluar los tiempos de inyección del mencionado gas, durante la producción de biomasa que conlleve a una mayor densidad celular, evaluando además, la variación del pH sin alterar la calidad del cultivo. A partir de seis cepas obtenidas del Banco de Germoplasma del Instituto del Mar del Perú, se realizaron cultivos tipo batch de 300L en invernadero, el tiempo de cultivo de la fase exponencial donde se realizaron las pruebas fue de tres días. Los datos se procesaron mediante el análisis del parámetro pendiente de la regresión lineal. Los resultados mostraron que la densidad celular es inversamente proporcional al tiempo de inyección de CO2 al cultivo. La mayor densidad celular, en las diferentes cepas, se obtuvo a los 5min, excepto para las cepas Chaetoceros gracilisy Nannochloris maculata, las cuales obtienen la mayor densidad a los 10 y 15min, respectivamente. La variación de pH tendió hacia la acidez, en un rango de 8 a 4, sin alterar la densidad celular, por el contrario, los cultivos permanecieron libres de contaminantes. En conclusión, los resultados permiten establecer tiempos adecuados de inyección del CO2, los cuales fortalecen la fase de crecimiento exponencial aumentando la densidad poblacional en un 30% sobre lo establecido en esta fase.

  2. Inducción de la producción de lípidos totales en microalgas sometidas a estrés nutritivo

    Directory of Open Access Journals (Sweden)

    Marianela Cobos Ruiz

    2016-01-01

    Full Text Available Se evaluó la producción de lípidos totales en cinco especies de microalgas inducidas por la ausencia de nitrógeno. Las microalgas empleadas fueron Ankistrodesmus sp., Ankistrodesmus nannoselene, Chlorella sp., Scenedesmus sp. y Scenedesmus quadricauda. Estas especies fueron cultivadas en medio CHU10 con y sin nitrógeno. El tiempo de evaluación fue de seis días, determinándose diariamente la densidad microalgal mediante recuento en cámara de Neubahuer. Se determinó la tasa de crecimiento, la biomasa microalgal y el porcentaje de lípidos totales. Los lípidos totales fueron extraídos con solución Cloroformo:metanol (2:1. Los resultados indicaron que las especies con mayor producción de lípidos totales fueron Ankistrodesmus sp. (263,6 mg/g biomasa seca, A. nannoselene (316 mg/g biomasa seca y Scenedesmus sp. (243,3 mg/g biomasa seca al ser cultivadas en medios sin nitrógeno. Scenedesmus quadricauda y Chlorella sp., fueron las especies que mostraron mayor producción de biomasa seca (159,1 mg/g biomasa seca y 221,1 mg/g biomasa seca respectivamente en medios con nitrógeno. La tasa de crecimiento fue variable entre las especies cultivadas en ambas condiciones. En conclusión, Ankistrodesmus sp., mostró la mayor tasa de crecimiento (0,77 dia-1 en medio sin nitrógeno. Bajo las mismas condiciones de cultivo, Scenedesmus sp. obtuvo la mayor producción de biomasa en peso seco (174,7 mg/l y Ankistrodesmus nannoselene acumuló el mayor porcentaje de lípidos totales.

  3. Desempenho, características de carcaça e expressão de genes em tourinhos alimentados com lipídeos e monensina

    Directory of Open Access Journals (Sweden)

    Márcio Machado Ladeira

    2014-09-01

    Full Text Available O objetivo deste trabalho foi avaliar o desempenho, as características de carcaça e as suas correlações com as expressões gênicas em tourinhos. Quarenta animais Red Norte foram confinados e distribuídos em delineamento inteiramente casualizado, em arranjo fatorial 2x2, e alimentados com grãos de soja moídos ou gordura protegida, com ou sem inclusão de monensina. As dietas foram formuladas para serem isonitrogenadas, com teores de extrato etéreo semelhante (6,5%, e tiveram silagem de milho como volumoso (40%. O período experimental foi de 84 dias, precedido por 14 dias de adaptação. Foram avaliadas as expressões dos genes PPARA, SREBP1c e SCD1. Animais alimentados com gordura protegida tiveram maior ganho de peso nos primeiros 56 dias de confinamento. O uso da monensina não afetou o ganho de peso diário dos animais, mas proporcionou aumento do rendimento de carcaça. Houve correlação de -0,40 entre o ganho de peso dos animais e a expressão do SCD1. O uso de gordura protegida aumenta o desempenho dos animais no início do confinamento, e a monensina proporciona maior rendimento de carcaça.

  4. Producción de Moina sp alimentada con Chlorella spp. cultivada con riles orgánicos de la industria pesquera cubana - Production of Moina sp fed with Chlorella spp. developed in organic waste waters from Cuban fishing industry

    OpenAIRE

    Romero Teresita de J; Manso Belkis; López Rafael; Martínez Fidel; Moreno Madelaine

    2010-01-01

    ResumenEl incremento importante de la acuicultura cubana y la carencia de algunos fertilizantes usados para fines de cultivo fitoplantónico, que finalmente pasan a nutrir especies zooplanctónicas como el cladócero Moina sp, ha motivado el presente estudio, referido al cultivo de dicha especie con la microalga Chlorella spp. desarrollada previamente con riles orgánicos de la industria pesquera.SummarySubstantial increase of Cuban acuiculture and deficiency of some fertilizers used for the phyt...

  5. Identification of characteristic fatty acids to quantify triacylglycerols in microalgae

    Directory of Open Access Journals (Sweden)

    Peili eShen

    2016-02-01

    Full Text Available The fatty acid profiles of lipids from microalgae are unique. Polyunsaturated fatty acids are generally enriched in polar lipids, whereas saturated and monounsaturated fatty acids constitute the majority of fatty acids in triacylglycerols (TAG. Each species has characteristic fatty acids, and their content is positively or negatively correlated with TAGs. The marine oleaginous diatom Phaeodactylum tricornutum was used as the paradigm to determine the quantitative relationship between TAG and characteristic fatty acid content. Fatty acid profiles and TAG content of Phaeodactylum tricornutum were determined in a time course. C16:0/C16:1 and eicosapentaenoic acid (EPA, C20:5n3 were identified as characteristic fatty acids in TAGs and polar lipids, respectively. The percentage of those characteristic fatty acids in total fatty acids had a significant linear relationship with TAG content and thus the correlation coefficient presenting r2 were 0.96, 0.94 and 0.97 respectively. The fatty acid-based method for TAG quantification could also be applied to other microalgae such as Nannochloropsis oceanica in which the r2 of C16:0, EPA were 0.94, 0.97 respectively and Chlorella pyrenoidosa, whose r2 value correspondingly between C18:1, C18:3 and TAG content were 0.91, 0.99 as well. This characteristic fatty acid-based method provided a distinct way to quantify TAGs in microalgae, by which TAGs could be measured precisely by immediate transesterification from wet biomass rather than using conventional methods. This procedure simplified the operation and required smaller samples than conventional methods.

  6. Impact of inorganic contaminants on microalgae productivity and bioremediation potential.

    Science.gov (United States)

    Torres, Eric M; Hess, Derek; McNeil, Brian T; Guy, Tessa; Quinn, Jason C

    2017-05-01

    As underdeveloped nations continue to industrialize and world population continues to increase, the need for energy, natural resources, and goods will lead to ever increasing inorganic contaminants, such as heavy metals, in various waste streams that can have damaging effects on plant life, wildlife, and human health. This work is focused on the evaluation of the potential of Nannochloropsis salina to be integrated with contaminated water sources for the concurrent production of a biofuel feedstock while providing an environmental service through bioremediation. Individual contaminants (As, Cd, Cr, Co, Cu, Pb, Ni, Hg, Se, and Zn) at various concentrations ranging from a low concentration (1X) to higher concentrations (10X, and 40X) found in contaminated systems (mine tailings, wastewater treatment plants, produced water) were introduced into growth media. Biological growth experimentation was performed in triplicate at the various contaminant concentrations and at 3 different light intensities. Results show that baseline concentrations of each contaminant slightly decreased biomass growth to between 89% and 99% of the control with the exception of Ni which dramatically reduced growth. Increased contaminant concentrations resulted in progressively lower growth rates for all contaminants tested. Lipid analysis shows most baseline contaminant concentrations slightly decrease or have minimal effects on lipid content at all light levels. Trace contaminant analysis on the biomass showed Cd, Co, Cu, Pb, and Zn were sorbed by the microalgae with minimal contaminants remaining in the growth media illustrating the effectiveness of microalgae to bioremediate these contaminants when levels are sufficiently low to not detrimentally impact productivity. The microalgae biomass was less efficient at sorption of As, Cr, Ni, and Se. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Adaptation of microalgae to a gradient of continuous petroleum contamination

    Energy Technology Data Exchange (ETDEWEB)

    Carrera-Martinez, Daniel; Mateos-Sanz, Aranzazu [AlgasGen Biotecnologia, EBT-UCM, Facultad de Veterinaria, Universidad Complutense de Madrid, Puerta de Hierro s/n, E-28040 Madrid (Spain); Lopez-Rodas, Victoria [AlgasGen Biotecnologia, EBT-UCM, Facultad de Veterinaria, Universidad Complutense de Madrid, Puerta de Hierro s/n, E-28040 Madrid (Spain); Genetica, Facultad de Veterinaria, Universidad Complutense de Madrid, Puerta de Hierro s/n, E-28040 Madrid (Spain); Costas, Eduardo, E-mail: ecostas@vet.ucm.es [AlgasGen Biotecnologia, EBT-UCM, Facultad de Veterinaria, Universidad Complutense de Madrid, Puerta de Hierro s/n, E-28040 Madrid (Spain); Genetica, Facultad de Veterinaria, Universidad Complutense de Madrid, Puerta de Hierro s/n, E-28040 Madrid (Spain)

    2011-01-25

    In order to study adaptation of microalgae to petroleum contamination, we have examined an environmental stress gradient by crude oil contamination in the Arroyo Minero River (AMR), Argentina. Underground crude oil has constantly leaked out since 1915 as a consequence of test drilling for possible petroleum exploitation. Numerous microalgae species proliferated in AMR upstream of the crude oil spill. In contrast, only four microalgal species were detected in the crude oil spill area. Species richness increases again downstream. Microalgae biomass in the crude oil spill area is dominated by a mesophile species, Scenedesmus sp. Effects of oil samples from AMR spill on photosynthetic performance and growth were studied using laboratory cultures of two Scenedesmus sp. strains. One strain (Se-co) was isolated from the crude oil spill area. The other strain (Se-pr) was isolated from a pristine area without petroleum contamination. Crude oil has undetectable effects on Se-co strain. In contrast crude oil rapidly destroys Se-pr strain. However, Se-pr strain can adapt to low doses of petroleum ({<=}3% v/v total hydrocarbons/water) by means of physiological acclimatization. In contrast, only rare crude oil-resistant mutants are able to grow under high levels of crude oil ({>=}10% v/v total hydrocarbons/water). These crude oil-resistant mutants have arisen through rare spontaneous mutations that occur prior to crude oil exposure. Species richness in different areas of AMR is closely connected to the kind of mechanism (genetic adaptation vs. physiological acclimatization) that allows adaptation. Resistant-mutants are enough to assure the survival of microalgal species under catastrophic crude oil spill.

  8. Research of Biogas Purification Using Microalgae Monoraphidium Griffithii Suspension

    Directory of Open Access Journals (Sweden)

    Živilė Bingelytė

    2017-09-01

    Full Text Available Using biogas instead of fossil fuels decreases pollutants such as solid particles, sulphur dioxide, nitrogen oxides concentrations in the environment. Green energy and development of relevant infrastructure improves air quality considerably. Chemical, physical, biological methods are used for biogas purification. The main difficulties using biological methods are selection of suitable microorganisms’ suspensions and making optimal conditions in photobioreactor. Different origin and structure microalgae suspensions are used applying biological treatment methods. Monoraphidium griffithi, which is widespread in fresh water, has relatively high potential. Microalgae’ cultures absorb the main components of biogas – carbon dioxide (CO2 and hydrogen sulphide (H2S. Absorbtion processes are based on photosynthesis. Microalgae absorb specific components of biogas when there are suitable light source and nutrient solvent. The main purposes of the research are to asses emission of biogas using different substrates (chicken manure and wastewater sludge. Also, it was measured main physical and chemical characteristics of both substrates: acidicy, temperature, redox potential, conductivity, biohemical oxygen demand. According results of the research, emission from wastewater sludge is greater than from chicken manure so sludge was chosen in teh next stage of the research. The next stage – asssessment of purification efficienty using Monoraphidium grifftihii suspension. Raw biogas was supplied to photobioreacor (with microalgae suspension. Alterations of methane, carbon dioxide, oxygen, hydrogen sulphide concentrations were measured precisely. According to results concentration of methane in the beginning of the researc was 62%, after 35 days – 69%. Meanwhile carbon dioxide – 37% and 31% by analogy. Experimental research alows to assess Monoraphidium griffithi absorption capacity of ballast components. Results were compared to different scientists

  9. Adaptation of microalgae to a gradient of continuous petroleum contamination

    International Nuclear Information System (INIS)

    Carrera-Martinez, Daniel; Mateos-Sanz, Aranzazu; Lopez-Rodas, Victoria; Costas, Eduardo

    2011-01-01

    In order to study adaptation of microalgae to petroleum contamination, we have examined an environmental stress gradient by crude oil contamination in the Arroyo Minero River (AMR), Argentina. Underground crude oil has constantly leaked out since 1915 as a consequence of test drilling for possible petroleum exploitation. Numerous microalgae species proliferated in AMR upstream of the crude oil spill. In contrast, only four microalgal species were detected in the crude oil spill area. Species richness increases again downstream. Microalgae biomass in the crude oil spill area is dominated by a mesophile species, Scenedesmus sp. Effects of oil samples from AMR spill on photosynthetic performance and growth were studied using laboratory cultures of two Scenedesmus sp. strains. One strain (Se-co) was isolated from the crude oil spill area. The other strain (Se-pr) was isolated from a pristine area without petroleum contamination. Crude oil has undetectable effects on Se-co strain. In contrast crude oil rapidly destroys Se-pr strain. However, Se-pr strain can adapt to low doses of petroleum (≤3% v/v total hydrocarbons/water) by means of physiological acclimatization. In contrast, only rare crude oil-resistant mutants are able to grow under high levels of crude oil (≥10% v/v total hydrocarbons/water). These crude oil-resistant mutants have arisen through rare spontaneous mutations that occur prior to crude oil exposure. Species richness in different areas of AMR is closely connected to the kind of mechanism (genetic adaptation vs. physiological acclimatization) that allows adaptation. Resistant-mutants are enough to assure the survival of microalgal species under catastrophic crude oil spill.

  10. Carbon dioxide fixation by microalgae cultivated in open bioreactors

    Energy Technology Data Exchange (ETDEWEB)

    Centeno da Rosa, Ana Priscila; Fernandes Carvalho, Lisiane; Goldbeck, Luzia [Laboratory of Biochemical Engineering, College of Chemistry and Food, Federal University of Rio Grande (FURG), P.O. Box 474, Rio Grande, RS 96201-900 (Brazil); Vieira Costa, Jorge Alberto, E-mail: dqmjorge@furg.br [Laboratory of Biochemical Engineering, College of Chemistry and Food, Federal University of Rio Grande (FURG), P.O. Box 474, Rio Grande, RS 96201-900 (Brazil)

    2011-08-15

    Highlights: {yields} We studied the growth and CO{sub 2} fixation by Spirulina LEB18 and Chlorella kessleri. {yields} The maximum dailyfixation was obtained for Spirulina with an injection of 6% of CO{sub 2}. {yields} The microalgae presented growth during the 20 d of culture with up to 18% of CO{sub 2}. {yields} The use of CO{sub 2} from industrial generation decreases the cost of producing biomass. - Abstract: The biofixation of carbon dioxide (CO{sub 2}) by microalgae has been proven to be an efficient and economical method, mainly due to the photosynthetic ability of these microorganisms to use this gas as a source of nutrients for their development. The aim of this work was to study the growth of Spirulina LEB18 and Chlorella kessleri microalgae, exposed to controlled and non-controlled conditions, with the injection of different concentrations of CO{sub 2}. The cultures was carried out in 6 L open raceway ponds, under controlled conditions at 30 {sup o}C and 39 {mu}E m{sup -2} s{sup -1} and under non-controlled conditions, protected by a tunnel of transparent film. The experiments were subjected to CO{sub 2} injections at concentrations of 0.038, 6, 12 and 18% (v/v). The highest concentration of biomass (4.95 g L{sup -1}) and maximum daily fixation (0.21 g g{sup -1} d{sup -1}) were obtained for Spirulina LEB18 in culture that was prepared in non-controlled conditions with an injection of 6% (v/v) of CO{sub 2}. C. kessleri had maximum (p < 0.0008) specific growth rate (0.84 d{sup -1}) when grown with 18% (v/v) of CO{sub 2} in non-controlled conditions of cultivation.

  11. Carbon dioxide fixation by microalgae cultivated in open bioreactors

    International Nuclear Information System (INIS)

    Centeno da Rosa, Ana Priscila; Fernandes Carvalho, Lisiane; Goldbeck, Luzia; Vieira Costa, Jorge Alberto

    2011-01-01

    Highlights: → We studied the growth and CO 2 fixation by Spirulina LEB18 and Chlorella kessleri. → The maximum dailyfixation was obtained for Spirulina with an injection of 6% of CO 2 . → The microalgae presented growth during the 20 d of culture with up to 18% of CO 2 . → The use of CO 2 from industrial generation decreases the cost of producing biomass. - Abstract: The biofixation of carbon dioxide (CO 2 ) by microalgae has been proven to be an efficient and economical method, mainly due to the photosynthetic ability of these microorganisms to use this gas as a source of nutrients for their development. The aim of this work was to study the growth of Spirulina LEB18 and Chlorella kessleri microalgae, exposed to controlled and non-controlled conditions, with the injection of different concentrations of CO 2 . The cultures was carried out in 6 L open raceway ponds, under controlled conditions at 30 o C and 39 μE m -2 s -1 and under non-controlled conditions, protected by a tunnel of transparent film. The experiments were subjected to CO 2 injections at concentrations of 0.038, 6, 12 and 18% (v/v). The highest concentration of biomass (4.95 g L -1 ) and maximum daily fixation (0.21 g g -1 d -1 ) were obtained for Spirulina LEB18 in culture that was prepared in non-controlled conditions with an injection of 6% (v/v) of CO 2 . C. kessleri had maximum (p -1 ) when grown with 18% (v/v) of CO 2 in non-controlled conditions of cultivation.

  12. Micro-algae as a source of protein.

    Science.gov (United States)

    Becker, E W

    2007-01-01

    About five decades ago, the mass production of certain protein-rich micro-algae was considered as a possibility to close the predicted so called "protein gap". Comprehensive analyses and nutritional studies have demonstrated that these algal proteins are of high quality and comparable to conventional vegetable proteins. However, due to high production costs as well as technical difficulties to incorporate the algal material into palatable food preparations, the propagation of algal protein is still in its infancy. To date, the majority of micro-algal preparations are marketed as health food, as cosmetics or as animal feed.

  13. Antioxidative properties of some phototropic microalgae grown in waste water

    DEFF Research Database (Denmark)

    Safafar, Hamed; Jacobsen, Charlotte; Møller, Peter

    selecting the species to be used for fish feed. The present study is part of a project which aims at developing new processing technologies, so that microalgae-biomass can be used as an alternative valuable resource in fish feed. Lipid and protein composition as well as antioxidative properties were used...... for the screening and selection of the species. In this study,the potential antioxidant activities of 12 micro algal sample from Chlorella., Spirulina., Euglena, Scenedesmus and Haematococcus species grown in waste water in Kalundborg micro algal facilities were evaluated using three antioxidant assays, including...

  14. Recent developments on biofuels production from microalgae and macroalgae

    DEFF Research Database (Denmark)

    Kumar, Kanhaiya; Ghosh, Supratim; Angelidaki, Irini

    2016-01-01

    Biofuels from algae are considered as promising alternatives of conventional fossil fuels, as they can eliminate most of the environmental problems. The present study focuses on all the possible avenues of biofuels production through biochemical and thermochemical conversion methods in one place...... and infrastructure requirement. Hydrogen production by microalgae through biophotolysis seems interesting as it directly converts the solar energy into hydrogen. However, the process has not been scaled-up till today. Hydrothermal liquefaction (HTL) is more promising due to handling of wet biomass at moderate...... temperature and pressure and conversion of whole biomass into high quality oil. However, HTL process is energy intensive....

  15. Rationales and Approaches for Studying Metabolism in Eukaryotic Microalgae

    Directory of Open Access Journals (Sweden)

    Daniel Veyel

    2014-04-01

    Full Text Available The generation of efficient production strains is essential for the use of eukaryotic microalgae for biofuel production. Systems biology approaches including metabolite profiling on promising microalgal strains, will provide a better understanding of their metabolic networks, which is crucial for metabolic engineering efforts. Chlamydomonas reinhardtii represents a suited model system for this purpose. We give an overview to genetically amenable microalgal strains with the potential for biofuel production and provide a critical review of currently used protocols for metabolite profiling on Chlamydomonas. We provide our own experimental data to underpin the validity of the conclusions drawn.

  16. VARIACIÓN BROMATOLÓGICA DE LA LECHE DE CABRAS LAMANCHA ALIMENTADAS CON DIFERENTES FORRAJES

    Directory of Open Access Journals (Sweden)

    Luis Rodolfo Herrera-Campos

    2009-01-01

    Full Text Available El objetivo del presente trabajo fue determinar el efecto de los forrajes de sorgo, estrella africana y morera en la calidad de la leche de cabra. Este experimento se desarrolló en la Estación Experimental Alfredo Volio Mata de la Universidad de Costa Ri ca ubicada en Cartago, Costa Ri ca a 1.542 msnm, durante el último trimestre del 2007, con tres grupos de cabras de raza Lamancha y tres diferentes forrajes: morera (Morus alba, estrella africana (Cynodom nlemfluensis y sorgo negro forrajero (Sorghum almum. El modelo experimental empleado fue un cuadrado latino repe tido. La mayor producción de leche se dio con los animales que consumie ron estrella africana (1,06 kg de leche/animal/día; (p<0,01, seguidos por los que consumie ron la morera (0,89 kg de leche/animal/día y el sorgo negro (0,73 kg de leche/animal/día. El porcentaje de grasa, proteína, caseína, sólidos totales y sólidos no grasos fueron más altos en la leche de los animales alimentados con morera (p<0,01 y más bajos en los que ingirie ron estrella africana.

  17. Microalgae as platforms for production of recombinant proteins and valuable compounds: progress and prospects.

    Science.gov (United States)

    Gong, Yangmin; Hu, Hanhua; Gao, Yuan; Xu, Xudong; Gao, Hong

    2011-12-01

    Over the last few years microalgae have gained increasing interest as a natural source of valuable compounds and as bioreactors for recombinant protein production. Natural high-value compounds including pigments, long-chain polyunsaturated fatty acids, and polysaccharides, which have a wide range of applications in the food, feed, cosmetics, and pharmaceutical industries, are currently produced with nontransgenic microalgae. However, transgenic microalgae can be used as bioreactors for the production of therapeutic and industrially relevant recombinant proteins. This technology shows great promise to simplify the production process and significantly decrease the production costs. To date, a variety of recombinant proteins have been produced experimentally from the nuclear or chloroplast genome of transgenic Chlamydomonas reinhardtii. These include monoclonal antibodies, vaccines, hormones, pharmaceutical proteins, and others. In this review, we outline recent progress in the production of recombinant proteins with transgenic microalgae as bioreactors, methods for genetic transformation of microalgae, and strategies for highly efficient expression of heterologous genes. In particular, we highlight the importance of maximizing the value of transgenic microalgae through producing recombinant proteins together with recovery of natural high-value compounds. Finally, we outline some important issues that need to be addressed before commercial-scale production of high-value recombinant proteins and compounds from transgenic microalgae can be realized.

  18. Potential of microalgae in the bioremediation of water with chloride content.

    Science.gov (United States)

    Ramírez, M E; Vélez, Y H; Rendón, L; Alzate, E

    2017-10-23

    In this work it was carried out the bioremediation of water containing chlorides with native microalgae (MCA) provided by the Centre for study and research in biotechnology (CIBIOT) at Universidad Pontificia Bolivariana. Microalgae presented an adaptation to the water and so the conditions evaluated reaching a production of CO2 in mg L-1 of 53.0, 26.6, 56.0, 16.0 and 30.0 and chloride removal efficiencies of 16.37, 26.03, 40.04, 25.96 and 20.25% for microalgae1, microalgae2, microalgae3, microalgae4 and microalgae5 respectively. Water bioremediation process was carried out with content of chlorides in fed batch system with an initial concentration of chlorides of 20585 mg L-1 every 2 days. The Manipulated variables were: the flow of MCA3 (10% inoculum) for test one; NPK flow for test two, and flow of flow of MCA3+0.5 g L-1 NPK. Chloride removal efficiencies were 66.88%, 63.41% and 66.98% for test one, two and three respectively, for a total bioprocess time of 55 days.

  19. Potential of microalgae in the bioremediation of water with chloride content

    Directory of Open Access Journals (Sweden)

    M. E. Ramírez

    2017-10-01

    Full Text Available Abstract In this work it was carried out the bioremediation of water containing chlorides with native microalgae (MCA provided by the Centre for study and research in biotechnology (CIBIOT at Universidad Pontificia Bolivariana. Microalgae presented an adaptation to the water and so the conditions evaluated reaching a production of CO2 in mg L-1 of 53.0, 26.6, 56.0, 16.0 and 30.0 and chloride removal efficiencies of 16.37, 26.03, 40.04, 25.96 and 20.25% for microalgae1, microalgae2, microalgae3, microalgae4 and microalgae5 respectively. Water bioremediation process was carried out with content of chlorides in fed batch system with an initial concentration of chlorides of 20585 mg L-1 every 2 days. The Manipulated variables were: the flow of MCA3 (10% inoculum for test one; NPK flow for test two, and flow of flow of MCA3+0.5 g L-1 NPK. Chloride removal efficiencies were 66.88%, 63.41% and 66.98% for test one, two and three respectively, for a total bioprocess time of 55 days.

  20. Microalgae population dynamics in photobioreactors with secondary sewage effluent as culture medium.

    Science.gov (United States)

    Marchello, Adriano E; Lombardi, Ana T; Dellamano-Oliveira, Maria José; de Souza, Clovis W O

    2015-03-01

    Nitrogen and phosphorus present in sewage can be used for microalgae growth, possibiliting cost reduction in the production of microalgae at the same time that it decreases the eutrophication potential of the effluent. This research aimed at monitoring the native community of microalgae and coliform bacteria in a secondary effluent from anaerobic municipal sewage treatment. Two treatments (aerated and non-aerated) were performed to grow microalgae under semi-controlled conditions in semi-closed photobioreactors in a greenhouse. The results showed no significant pH and coliforms (total and Escherichia coli ) variation between treatments. Nutrient concentrations were reduced supporting microalgae growth up to 10 (7) cells.mL (-1) independent of aeration. Exponential growth was obtained from the first day for the non-aerated, but a 5 day lag phase of growth was obtained for the aerated. Chlorella vulgaris was the dominant microalgae (99.9%) in both treatments. In the aerated, 5 algae classes were detected (Chlorophyceae, Cyanophyceae, Chrysophyceae, Bacillariophyceae and Euglenophyceae), with 12 taxa, whereas in the non-aerated, 2 classes were identified (Chlorophyceae and Cyanophyceae), with 5 taxa. We concluded that effluent is viable for microalgae growth, especially Chlorella vulgaris, at the same time that the eutrophication potential and coliforms are decreased, contributing for better quality of the final effluent.

  1. Microalgae population dynamics in photobioreactors with secondary sewage effluent as culture medium

    Directory of Open Access Journals (Sweden)

    Adriano E. Marchello

    2015-03-01

    Full Text Available Nitrogen and phosphorus present in sewage can be used for microalgae growth, possibiliting cost reduction in the production of microalgae at the same time that it decreases the eutrophication potential of the effluent. This research aimed at monitoring the native community of microalgae and coliform bacteria in a secondary effluent from anaerobic municipal sewage treatment. Two treatments (aerated and non-aerated were performed to grow microalgae under semi-controlled conditions in semi-closed photobioreactors in a greenhouse. The results showed no significant pH and coliforms (total and Escherichia coli variation between treatments. Nutrient concentrations were reduced supporting microalgae growth up to 107 cells.mL−1independent of aeration. Exponential growth was obtained from the first day for the non-aerated, but a 5 day lag phase of growth was obtained for the aerated. Chlorella vulgaris was the dominant microalgae (99.9% in both treatments. In the aerated, 5 algae classes were detected (Chlorophyceae, Cyanophyceae, Chrysophyceae, Bacillariophyceae and Euglenophyceae, with 12 taxa, whereas in the non-aerated, 2 classes were identified (Chlorophyceae and Cyanophyceae, with 5 taxa. We concluded that effluent is viable for microalgae growth, especially Chlorella vulgaris, at the same time that the eutrophication potential and coliforms are decreased, contributing for better quality of the final effluent.

  2. The Potential Use of Marine Microalgae and Cyanobacteria in Cosmetics and Thalassotherapy

    Directory of Open Access Journals (Sweden)

    M. Lourdes Mourelle

    2017-11-01

    Full Text Available The use of microalgae and cyanobacteria for nutritional purposes dates back thousands of years; during the last few decades, microalgae culture has improved to become one of the modern biotechnologies. This has allowed high amounts of algal biomass to be obtained for use in different applications. Currently, the global production of microalgae and cyanobacteria is predominately aimed at applications with high added value given that algal biomass contains pigments, proteins, essential fatty acids, polysaccharides, vitamins, and minerals, all of which are of great interest in the preparation of natural products, both as food and in cosmetics. Hence, the bioactive components from microalgae can be incorporated in cosmetic and cosmeceutical formulations, and can help achieve benefits including the maintenance of skin structure and function. Thalassotherapy involves using seawater and all related marine elements, including macroalgae, however, there has been limited use of microalgae. Microalgae and cyanobacteria could be incorporated into health and wellness treatments applied in thalassotherapy centers due to their high concentration of biologically active substances that are of interest in skin care. This paper briefly reviews the current and potential cosmetic and cosmeceutical applications of marine microalgae and cyanobacteria compounds and also recommends its use in thalassotherapy well-being treatments.

  3. Microalgae population dynamics in photobioreactors with secondary sewage effluent as culture medium

    Science.gov (United States)

    Marchello, Adriano E.; Lombardi, Ana T.; Dellamano-Oliveira, Maria José; de Souza, Clovis W.O.

    2015-01-01

    Nitrogen and phosphorus present in sewage can be used for microalgae growth, possibiliting cost reduction in the production of microalgae at the same time that it decreases the eutrophication potential of the effluent. This research aimed at monitoring the native community of microalgae and coliform bacteria in a secondary effluent from anaerobic municipal sewage treatment. Two treatments (aerated and non-aerated) were performed to grow microalgae under semi-controlled conditions in semi-closed photobioreactors in a greenhouse. The results showed no significant pH and coliforms (total and Escherichia coli ) variation between treatments. Nutrient concentrations were reduced supporting microalgae growth up to 10 7 cells.mL −1 independent of aeration. Exponential growth was obtained from the first day for the non-aerated, but a 5 day lag phase of growth was obtained for the aerated. Chlorella vulgaris was the dominant microalgae (99.9%) in both treatments. In the aerated, 5 algae classes were detected (Chlorophyceae, Cyanophyceae, Chrysophyceae, Bacillariophyceae and Euglenophyceae), with 12 taxa, whereas in the non-aerated, 2 classes were identified (Chlorophyceae and Cyanophyceae), with 5 taxa. We concluded that effluent is viable for microalgae growth, especially Chlorella vulgaris, at the same time that the eutrophication potential and coliforms are decreased, contributing for better quality of the final effluent. PMID:26221091

  4. Towards a luxury uptake process via microalgae--defining the polyphosphate dynamics.

    Science.gov (United States)

    Powell, Nicola; Shilton, Andy; Chisti, Yusuf; Pratt, Steven

    2009-09-01

    Microalgae in waste stabilization ponds (WSP) have been shown to accumulate polyphosphate. This luxury uptake of phosphorus is influenced by the wastewater phosphate concentration, light intensity and temperature, but the dynamics of how these factors affect luxury uptake with respect to time are not understood. With improved understanding of the dynamics of this mechanism and how it could be manipulated, a phosphorus removal process utilizing luxury uptake by microalgae might be developed. In this work, luxury uptake was investigated by chemical extraction of the acid-soluble and acid-insoluble fractions of polyphosphate in the microalgae. The results showed that the initial accumulation and subsequent utilization of both acid-soluble polyphosphate (ASP) and acid-insoluble polyphosphate (AISP) is a function of the wastewater phosphate concentration. It was found that light intensity influenced both the accumulation and utilization of ASP. The temperature influenced the accumulation of AISP. AISP is believed to be a form of phosphorus storage and ASP is involved in metabolism however, the results of this work show that ASP can also act as a short term form of phosphorus storage. To optimize luxury uptake by microalgae a 'luxury uptake pond' is proposed where the conditions the microalgae are exposed to can be manipulated. This 'luxury uptake pond' would be designed to expose the microalgae to a high phosphate concentration and high light intensity for a short period of time in order to achieve optimal polyphosphate accumulation. Subsequent harvesting would then remove the phosphorus rich microalgae from the system.

  5. Impact of Microalgae-Bacteria Interactions on the Production of Algal Biomass and Associated Compounds.

    Science.gov (United States)

    Fuentes, Juan Luis; Garbayo, Inés; Cuaresma, María; Montero, Zaida; González-Del-Valle, Manuel; Vílchez, Carlos

    2016-05-19

    A greater insight on the control of the interactions between microalgae and other microorganisms, particularly bacteria, should be useful for enhancing the efficiency of microalgal biomass production and associated valuable compounds. Little attention has been paid to the controlled utilization of microalgae-bacteria consortia. However, the studies of microalgal-bacterial interactions have revealed a significant impact of the mutualistic or parasitic relationships on algal growth. The algal growth, for instance, has been shown to be enhanced by growth promoting factors produced by bacteria, such as indole-3-acetic acid. Vitamin B12 produced by bacteria in algal cultures and bacterial siderophores are also known to be involved in promoting faster microalgal growth. More interestingly, enhancement in the intracellular levels of carbohydrates, lipids and pigments of microalgae coupled with algal growth stimulation has also been reported. In this sense, massive algal production might occur in the presence of bacteria, and microalgae-bacteria interactions can be beneficial to the massive production of microalgae and algal products. This manuscript reviews the recent knowledge on the impact of the microalgae-bacteria interactions on the production of microalgae and accumulation of valuable compounds, with an emphasis on algal species having application in aquaculture.

  6. Progress in microalgae cultivation photobioreactors and applications in wastewater treatment: A review

    Directory of Open Access Journals (Sweden)

    Lu Haifeng

    2017-01-01

    Full Text Available Using microalgae to treat wastewater has received growing attention in the world because it is regarded as a novel means for wastewater treatment. It is commonly recognized that large-scale cultivation and commercial application of microalgae are limited by the development of photobioreactor (PBR. Although there are a lot of PBRs for microalgae pure cultivation which used culture medium, specialized PBRs designed for wastewater treatment are rare. The composition of wastewater is quite complicated; this might cause a very different photosynthetic effect of microalgae compared to those grown in a pure cultivation medium. Therefore, PBRs for wastewater treatment need to be redesigned and improved based on the existing PBRs that are used for microalgae pure cultivation. In this review, different PBRs for microalgae cultivation and wastewater treatment are summarized. PBR configurations, PBR design parameters and types of wastewater are presented. In addition, the wastewater treatment efficiency and biomass productivity were also compared among each type of PBRs. Moreover, some other promising PBRs are introduced in this review, and a two-stage cultivation mode which combines both closed and open system is discussed as well. Ultimately, this article focuses on current problems and gives an outlook for this field, aiming at providing a primary reference for microalgae cultivation by using wastewater.

  7. [Identification of Microalgae Species Using Visible/Near Infrared Transmission Spectroscopy].

    Science.gov (United States)

    Zhu, Hong-yan; Shao, Yong-ni; Jiang, Lu-lu; Guo, An-que; Pan, Jian; He, Yong

    2016-01-01

    At present, the identification and classification of the microalgae and its biochemical analysis have become one of the hot spots on marine biology research. Four microalgae species, including Chlorella vulgaris, Chlorella pyrenoidosa, Nannochloropsis oculata, Chlamydomonas reinhardtii, were chosen as the experimental materials. Using an established spectral acquisition system, which consists of a portable USB 4000 spectrometer having transmitting and receiving fiber bundles connected by a fiber optic probe, a halogen light source, and a computer, the Vis/NIR transmission spectral data of 120 different samples of the microalgae with different concentration gradients were collected, and the spectral curves of fourmicroalgae species were pre-processed by different pre-treatment methods (baseline filtering, convolution smoothing, etc. ). Based on the pre-treated effects, SPA was applied to select effective wavelengths (EWs), and the selected EWs were introduced as inputs to develop and compare PLS, Least Square Support Vector Machines (LS-SVM), Extreme Learning Machine (ELM)models, so as to explore the feasibility of using Vis/NIR transmission spectroscopy technology for the rapid identification of four microalgae species in situ. The results showed that: the effect of Savitzky-Golay smoothing was much better than the other pre-treatment methods. Six EWs selected in the spectraby SPA were possibly relevant to the content of carotenoids, chlorophyll in the microalgae. Moreover, the SPA-PLS model obtained better performance than the Full-Spectral-PLS model. The average prediction accuracy of three methods including SPA-LV-SVM, SPA-ELM, and SPA-PLS were 80%, 85% and 65%. The established method in this study may identify four microalgae species effectively, which provides a new way for the identification and classification of the microalgae species. The methodology using Vis/NIR spectroscopy with a portable optic probe would be applicable to a diverse range of microalgae

  8. Evaluation of alternatives for microalgae oil extraction based on exergy analysis

    International Nuclear Information System (INIS)

    Peralta-Ruiz, Y.; González-Delgado, A.-D.; Kafarov, V.

    2013-01-01

    Highlights: ► Exergy analysis was used as decision-making tool for evaluation of microalgae oil extraction. ► A robust composition of Chlorella sp. biomass was modeled and used for simulation. ► Three solvent-based microalgae oil extraction methods at large scale were compared. ► Hexane based extraction presented the highest exergetic efficiency. -- Abstract: Several technologies for microalgae oil extraction are being evaluated in order to find the most adequate for large scale microalgae processing. In this work, exergy analysis was used as an instrument for screening three design alternatives for microalgae oil extraction in a large-scale process and as a decision-making tool for evaluation and selection of novel technologies from the energy point of view. Routes were simulated using dedicated industrial process simulation software, taking as feedstock a representative and robust modeled composition of Chlorella sp. microalgae biomass. Mass, energy and exergy balances were performed for each alternative, and physical and chemical exergies of streams and all specific microalgae constituents modeled were calculated with the help of the thermodynamic properties of biomass components and operating conditions of streams. Exergetic efficiencies, total process irreversibilities, energy consumption and exergy destruction were calculated for all solvent-based microalgae oil extraction pathways evaluated. It was shown that exergy analysis led to identify the hexane-based oil extraction (HBE) as the most adequate alternative of the routes assessed for scaling up from the energy point of view, presenting a maximum exergy efficiency of 51% and exergetic losses of 982,000 MJ considering a production of 104,000 t of microalgae oil per year.

  9. MANEJO BIOTECNOLOGICO DE MICROALGAS OLEAGINOSAS NATIVAS PARA LA OBTENCION DE BIODIESEL

    OpenAIRE

    GOMEZ VERGARA, PATRICIA IVONNE

    2013-01-01

    El proyecto FONDEF D07I-1063 “Manejo biotecnológico de microalgas oleaginosas nativas para la obtención de biodiesel” tuvo como principal objetivo establecer las bases para el escalamiento industrial de la producción de biodiesel a partir de microalgas nativas, mediante la selección de cepas y la optimización de cultivos. Los resultados de producción obtenidos fueron: a) Cepario de microalgas nativas y mejoradas genéticamente para la producción de biodiesel, se aislaron y caracter...

  10. Use of Solid Waste from Thermoelectric Plants for the Cultivation of Microalgae

    Directory of Open Access Journals (Sweden)

    Bruna da Silva Vaz

    2016-01-01

    Full Text Available ABSTRACT The aim of this study was to analyze the influence of solid waste on the cultivation of the microalgae Spirulina sp. LEB 18 and Chlorella fusca LEB 111 with 0, 40, 80 and 120 ppm of mineral coal ash. The addition of the ash did not inhibit the cultivation of microalgae at the tested concentrations, showing that it could be used for the cultivation of these microalgae due to the minerals present in the ash, which might substitute the nutrients needed for their growth.

  11. Modifications of the metabolic pathways of lipid and triacylglycerol production in microalgae.

    Science.gov (United States)

    Yu, Wei-Luen; Ansari, William; Schoepp, Nathan G; Hannon, Michael J; Mayfield, Stephen P; Burkart, Michael D

    2011-11-02

    Microalgae have presented themselves as a strong candidate to replace diminishing oil reserves as a source of lipids for biofuels. Here we describe successful modifications of terrestrial plant lipid content which increase overall lipid production or shift the balance of lipid production towards lipid varieties more useful for biofuel production. Our discussion ranges from the biosynthetic pathways and rate limiting steps of triacylglycerol formation to enzymes required for the formation of triacylglycerol containing exotic lipids. Secondarily, we discuss techniques for genetic engineering and modification of various microalgae which can be combined with insights gained from research in higher plants to aid in the creation of production strains of microalgae.

  12. Active compounds from cyanobacteria and microalgae: properties and potential applications in biomedicine

    Directory of Open Access Journals (Sweden)

    Alexey Llopiz

    2016-05-01

    Full Text Available Cyanobacteria and microalgae are source of many chemicals substances with potential applications on biopharmaceutical industry. Many structures have been characterized in these organism, such as: peptides, proteins, carbohydrates, terpenoids, polyinsatured fatty acids, flavonoids, phenolic compounds, vitamins, porfirins and other organic substances. Chemicals structures of isolated compounds are diverse and it depends of microalgae habitats. Pharmacological activities located in microalgae are bactericides, immunomodulatory, antioxidants, cytoprotective, fungicides and antivirals. These properties may possible the potential treatment of many diseases including autoimmunes disorders, tumoral, and infectious process. In this review are presented and discussed some elements associated to chemical structure and biological activities around of compounds with potential uses as biopharmaceuticals.

  13. Evaluation of available saline water resources in New Mexico for the production of microalgae

    Energy Technology Data Exchange (ETDEWEB)

    Lansford, R.; Hernandez, J.; Enis, P.; Truby, D.; Mapel, C.

    1990-08-01

    Researchers evaluated saline water resources in New Mexico for their suitability as sites for large-scale microalgae production facilities. Production of microalgae could provide a renewable source of fuel, chemicals, and food. In addition, making use of the unused saline water resources would increase the economic activity in the state. After analyzing the 15 billion acre-ft of unused saline water resources in the state, scientists narrowed the locations down to six sites with the most potential. With further analysis, they chose the Tularosa Basin in southern New Mexico as the best-suited area for 100-hectare microalgae production facility. 34 refs., 38 figs., 14 tabs.

  14. Conversion of microalgae to jet fuel: process design and simulation.

    Science.gov (United States)

    Wang, Hui-Yuan; Bluck, David; Van Wie, Bernard J

    2014-09-01

    Microalgae's aquatic, non-edible, highly genetically modifiable nature and fast growth rate are considered ideal for biomass conversion to liquid fuels providing promise for future shortages in fossil fuels and for reducing greenhouse gas and pollutant emissions from combustion. We demonstrate adaptability of PRO/II software by simulating a microalgae photo-bio-reactor and thermolysis with fixed conversion isothermal reactors adding a heat exchanger for thermolysis. We model a cooling tower and gas floatation with zero-duty flash drums adding solids removal for floatation. Properties data are from PRO/II's thermodynamic data manager. Hydrotreating is analyzed within PRO/II's case study option, made subject to Jet B fuel constraints, and we determine an optimal 6.8% bioleum bypass ratio, 230°C hydrotreater temperature, and 20:1 bottoms to overhead distillation ratio. Process economic feasibility occurs if cheap CO2, H2O and nutrient resources are available, along with solar energy and energy from byproduct combustion, and hydrotreater H2 from product reforming. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Improving microalgae for biotechnology--From genetics to synthetic biology.

    Science.gov (United States)

    Hlavova, Monika; Turoczy, Zoltan; Bisova, Katerina

    2015-11-01

    Microalgae have traditionally been used in many biotechnological applications, where each new application required a different species or strain expressing the required properties; the challenge therefore is to isolate or develop, characterize and optimize species or strains that can express more than one specific property. In agriculture, breeding of natural variants has been successfully used for centuries to improve production traits in many existing plant and animal species. With the discovery of the concepts of classical genetics, these new ideas have been extensively used in selective breeding. However, many biotechnologically relevant algae do not possess the sexual characteristics required for traditional breeding/crossing, although they can be modified by chemical and physical mutagens. The resulting mutants are not considered as genetically modified organisms (GMOs) and their cultivation is therefore not limited by legislation. On the other hand, mutants prepared by random or specific insertion of foreign DNA are considered to be GMOs. This review will compare the effects of two genetic approaches on model algal species and will summarize their advantages in basic research. Furthermore, we will discuss the potential of mutagenesis to improve microalgae as a biotechnological resource, to accelerate the process from specific strain isolation to growth optimization, and discuss the production of new products. Finally, we will explore the potential of algae in synthetic biology. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Therapeutic Potentials of Microalgae in the Treatment of Alzheimer's Disease.

    Science.gov (United States)

    Olasehinde, Tosin A; Olaniran, Ademola O; Okoh, Anthony I

    2017-03-18

    Current research is geared towards the discovery of new compounds with strong neuroprotective potential and few or no side effects compared to synthetic drugs. This review focuses on the potentials of extracts and biologically active compounds derived from microalgal biomass for the treatment and management of Alzheimer's disease (AD). Microalgal research has gained much attention recently due to its contribution to the production of renewable fuels and the ability of alga cells to produce several secondary metabolites such as carotenoids, polyphenols, sterols, polyunsaturated fatty acids and polysaccharides. These compounds exhibit several pharmacological activities and possess neuroprotective potential. The pathogenesis of Alzheimer's disease (AD) involves complex mechanisms that are associated with oxidative stress, cholinergic dysfunction, neuronal damage, protein misfolding and aggregation. The antioxidant, anticholinesterase activities as well as the inhibitory effects of some bioactive compounds from microalgae extracts on β-amyloid aggregation and neuronal death are discussed extensively. Phytochemical compounds from microalgae are used as pharmaceuticals, nutraceuticals and food supplements, and may possess neuroprotective potentials that are relevant to the management and/or treatment of AD.

  17. Kinetic exploration of nitrate-accumulating microalgae for nutrient recovery.

    Science.gov (United States)

    Coppens, Joeri; Decostere, Bjorge; Van Hulle, Stijn; Nopens, Ingmar; Vlaeminck, Siegfried E; De Gelder, Leen; Boon, Nico

    2014-10-01

    Within sustainable resource management, the recovery of nitrogen and phosphorus nutrients from waste streams is becoming increasingly important. Although the use of microalgae has been described extensively in environmental biotechnology, the potential of nitrate-accumulating microalgae for nutrient recovery has not been investigated yet. The ability of these marine microorganisms to concentrate environmental nitrate within their biomass is remarkable. The aim of this study was to investigate the application potential of nitrate-accumulating diatoms for nutrient recovery from marine wastewaters. The intracellular nitrate storage capacity was quantified for six marine diatom strains in synthetic wastewater. Amphora coffeaeformis and Phaeodactylum tricornutum stored the highest amount of nitrate with respectively 3.15 and 2.10 g N L(-1) of cell volume, which accounted for 17.3 and 4.6 %, respectively, of the total nitrogen content. The growth and nitrate and phosphate uptake of both diatoms were further analyzed and based on these features P. tricornutum showed the highest potential for nutrient recovery. A mathematical model was developed which included intracellular nitrate storage and the kinetic parameters were derived for P. tricornutum. Furthermore, a simulation study was performed to compare the performance of a proposed microalgal nutrient recovery unit with a conventional denitrification system for marine wastewater treatment. Overall, this study demonstrates the potential application of P. tricornutum for saline wastewater treatment with concurrent nitrogen and phosphorus recycling.

  18. Cultivating Microalgae in Domestic Wastewater for Biodiesel Production

    Directory of Open Access Journals (Sweden)

    Soha S.M. MOSTAFA

    2012-02-01

    Full Text Available The objective of this study was to evaluate the growth of nine species of microalgae (green and blue green microalgae on domestic waste water samples obtained from Zenein Waste Water Treatment Plant (ZWWTP, Giza governorate, Egypt. The species were cultivated in different kind of waste water; before treatment; after sterilization; with nutrients with sterilization and with nutrients without sterilization. The experiment was conducted in triplicate and cultures were incubated at 25�1�C under continuous shaking (150 rpm and illumination (2000 Lux for 15 days. pH, electric conductivity (EC, optical density (OD , dry weight (DW, were done at the time of incubation and at the end of experiment, in addition to determine the percentage of lipid and biodiesel. The data revealed that, domestic waste water with nutrient media (T3 was promising for cultivation of five algal species when compared with conventional media, Moreover, domestic waste water after sterilization (T2 was selected media for cultivation of Oscillatoria sp and Phormedium sp. However, T1 media (waste water without treatment was the promising media for cultivation of Nostoc humifusum. The biodiesel produced from algal species cultivated in waste water media ranged from 3.8 to 11.80% when compared with the conventional method (3.90 to 12.52%. The results of this study suggest that growing algae in nutrient rich media offers a new option of applying algal process in ZWWTP to mange the nutrient load for growth and valuable biodiesel feedstock production.

  19. Paracetamol and salicylic acid removal from contaminated water by microalgae.

    Science.gov (United States)

    Escapa, C; Coimbra, R N; Paniagua, S; García, A I; Otero, M

    2017-12-01

    The biomass growth, pharmaceutical removal and light conversion efficiency of Chlorella sorokiniana under the presence of paracetamol (PC) and salicylic acid (SaC) were assessed and compared at two different concentrations of these pharmaceuticals (I: 25 mg l -1 , II: 250 mg l -1 ). Microalgae were resistant to these concentrations and, moreover, their growth was significantly stimulated (p ≤ 0.05) under these drugs (biomass concentration increased above 33% PCI, 35% SaCI, 13% PCII and 45% SaCII, as compared with the respective positive controls). At the steady state of the semicontinuous culture, C. sorokiniana showed removal efficiencies above 41% and 69% for PCI and PCII, respectively; and above 93% and 98% for SaCI and SaCII, respectively. Under an irradiance of 370 μE m -2  s -1 , higher quantum yields were reached by microalgae under the presence of drugs, either at dose I or II, than by the respective positive controls. These results point to C. sorokiniana as a robust strain for the bioremediation of paracetamol and salicylic acid concentrated wastewaters. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Thermochemical liquefaction characteristics of microalgae in sub- and supercritical ethanol

    Energy Technology Data Exchange (ETDEWEB)

    You, Qiao; Chen, Liang [College of Environmental Science and Engineering, Hunan University, Changsha (China); Key Laboratory of Environment Biology and Pollution Control, Ministry of Education, Changsha (China)

    2011-01-15

    Thermochemical liquefaction characteristics of Spirulina, a kind of high-protein microalgae, were investigated with the sub- and supercritical ethanol as solvent in a 1000 mL autoclave. The influences of various liquefaction parameters on the yields of products (bio-oil and residue) from the liquefaction of Spirulina were studied, such as the reaction temperature (T), the S/L ratio (R{sub 1}, solid: Spirulina, liquid: ethanol), the solvent filling ratio (R{sub 2}) and the type and dosage of catalyst. Without catalyst, the bio-oil yields were in the range of 35.4 wt.% and 45.3 wt.% depending on the changes of T, R{sub 1} and R{sub 2}. And the bio-oil yields increased generally with increasing T and R{sub 2}, while the bio-oil yields reduced with increasing R{sub 1}. The FeS catalyst was certified to be an ideal catalyst for the liquefaction of Spirulina microalgae for its advantages on promoting bio-oil production and suppressing the formation of residue. The optimal dosage of catalyst (FeS) was ranging from 5-7 wt.%. The elemental analyses and FT-IR and GC-MS measurements for the bio-oils revealed that the liquid products have much higher heating values than the crude Spirulina sample and fatty acid ethyl ester compounds were dominant in the bio-oils, irrespective of whether catalyst was used. (author)

  1. Anaerobic Co-Digestion of the Microalgae Scenedesmus Sp.

    Energy Technology Data Exchange (ETDEWEB)

    Ramos-Suarez, J. L.; Carreras, N.

    2011-06-07

    Microalgae biomass has been widely studied for biogas production over the last years and results show that anaerobic digestion is often limited by the low C/N ratio of this type of biomass. Therefore, codigestion with substrates of high C/N ratio is necessary. The objectives of this study are to set up an experimental method that ease reproducibility and control of anaerobic digestion processes in laboratory conditions and to determine the biodegradability and biogas production potential of the co-digestion process of microalgae Scenedesmus sp. and energy crop Opuntia ficus indica (L.) Miller. Results obtained showed that higher C/N ratios are preferred in order to maximize methane production. Highest methane yield obtained was 0.252m3CH4/Kg VS and degradability expressed as percentage COD reduced is around 30% for the ideal mixture found, made up of 75% O. ficus-indica and 25% Scenedesmus sp. in VS basis. A laboratory setup using MicroOxymax respirometer, after its adaptation to work under anaerobic conditions, can be used for the monitoring of anaerobic digestion processes. Scenedesmus sp. as sole substrate for anaerobic digestion does not give good results due to low C/N ratio. However, when codigesting it with O. ficus-indica methane production is satisfactory. Best mixture was made up of 75% O. ficus-indica and 25% Scenedesmus sp. in VS basis. (Author)

  2. Micro-algae: French players discuss the matter

    International Nuclear Information System (INIS)

    Bouveret, T.

    2013-01-01

    About 75000 species of algae have been reported so far, the domains of application are huge and investment are increasing all around the world. One of the difficulties is to find the most appropriate algae to a specific application. Some development programs have failed scientifically or economically for instance the production of protein for animal food from the chlorella algae or the production of bio-fuel from C14-C18 chains, from zeaxanthine and from phycoerytrine. On the other side some research programs have led to promising industrial applications such as the production of food for fish and farm animals. Some research fields are completely innovative such as the use of micro-algae for the construction of bio-walls for buildings. Micro-algae are diverse and fragile. Photo-bioreactors have been designed to breed fragile algae like some types of chlorophycees used in bio-fuel and in cosmetics, a prototype has been tested for 15 months and its production is about 2 kg of dry matter a day. (A.C.)

  3. Ultrastructural and flow cytometric analyses of lipid accumulation in microalgae

    Energy Technology Data Exchange (ETDEWEB)

    Solomon, J.A.; Hand, R.E. Jr.; Mann, R.C.

    1986-12-01

    Lipid accumulation in three species of microalgae was investigated with flow cytometry (FCM) and transmission electron microscopy (TEM). Previous studies using batch cultures of a algae have led to the assumption that lipid accumulation in microalgae is a gradual process requiring at least several days for completion. However, FCM reveals, through changes in the chlorophyll:lipid ratio, that the time span required for individual cells to change metabolic state is short. Simultaneous FCM measurements of chlorophyll and nile red (neutral lipid) fluorescence in individual cells of nitrogen-deficient Isochrysis populations revealed a bimodal population distribution as one stage in the lipid accumulation process. The fact that two discrete populations exist, with few cells in an intermediate stage, suggests rapid response to a liqid trigger. Interpretations of light and electron microscopic observations are consistent with this hypothesis. The time required for an entire population to achieve maximum lipid content is considerably longer than that required for a single cell, due to the variation in response time among cells. In this study high lipid cultures were sometimes obtained by using FCM to separate high lipid cells from the remainder of the population. FCM holds much promise for strain enhancement but considerable developmental work, directed at providing more consistent results, remains to be done. 8 refs., 35 figs.

  4. Cyanobacteria and microalgae: a positive prospect for biofuels.

    Science.gov (United States)

    Parmar, Asha; Singh, Niraj Kumar; Pandey, Ashok; Gnansounou, Edgard; Madamwar, Datta

    2011-11-01

    Biofuel-bioenergy production has generated intensive interest due to increased concern regarding limited petroleum-based fuel supplies and their contribution to atmospheric CO2 levels. Biofuel research is not just a matter of finding the right type of biomass and converting it to fuel, but it must also be economically sustainable on large-scale. Several aspects of cyanobacteria and microalgae such as oxygenic photosynthesis, high per-acre productivity, non-food based feedstock, growth on non-productive and non-arable land, utilization of wide variety of water sources (fresh, brackish, seawater and wastewater) and production of valuable co-products along with biofuels have combined to capture the interest of researchers and entrepreneurs. Currently, worldwide biofuels mainly in focus include biohydrogen, bioethanol, biodiesel and biogas. This review focuses on cultivation and harvesting of cyanobacteria and microalgae, possible biofuels and co-products, challenges for cyanobacterial and microalgal biofuels and the approaches of genetic engineering and modifications to increase biofuel production. Copyright © 2011 Elsevier Ltd. All rights reserved.

  5. Microalgae and Its Premises towards Sustainable Energy Development

    Science.gov (United States)

    Chik, M. N.; Yahya, L.; Zainal, A.; Boosroh, M. H.

    2017-06-01

    This paper features the use of nature’s element as a tool to combat current global issues on environment. Through research works by TNB Research Sdn. Bhd. (TNBR), marine phototrophic microalgae is used in reducing CO2 emissions from its fossil-fuel based power plants using. The research program commenced in 2011 with the aim to develop capacity, capability and facilities in biological CO2 fixation. The research program focuses on improving and enhancing the CO2 fixation through four core measures; namely species selection, nutrient optimization, flue gas admission and photobioreactor (PBR) design and engineering. The measures lead to the migration and evolution of culture facilities from laboratory conditions to outdoor, from shake flasks to 6 x 250 liter pilot PBR facility at a live coal-fired power plant, from mono species to consortium of species. Increment of CO2 fixation rates is summarized with discussion on comparisons of other achievements reported elsewhere. A considerable amount of work on analysing the bioactive compound present in the algae - protein, amino acids, carbohydrate, lipid, fatty acids - and its encouraging results, as an impetus towards sustainable development, will also be shared. Premises and observations from various microalgae research works are collated and presented in a manner sufficient to highlight the eminent roles of this tiny creature to become our mentor in providing some solutions to our worldly problems.

  6. Optimizing carbon dioxide utilization for microalgae biofilm cultivation.

    Science.gov (United States)

    Blanken, Ward; Schaap, Stefan; Theobald, Sophie; Rinzema, Arjen; Wijffels, René H; Janssen, Marcel

    2017-04-01

    The loss of carbon dioxide (CO 2 ) to the environment during microalgae cultivation is undesirable for both environmental and economic reasons. In this study, a phototrophic biofilm growth model was developed and validated with the objective to maximize both CO 2 utilization efficiency and production of microalgae in biofilms. The model was validated in growth experiments with CO 2 as the limiting substrate. The CO 2 utilization and biomass productivity were maximized by changing the gas flow rate, the number of biofilm reactors in series and gas composition. Based on simulations, the maximum CO 2 utilization efficiency that was reached was 96% based on a process employing flue gas. The corresponding drop in productivity was only 2% in comparison to the non-CO 2 limited reference situation. In order to achieve this, 25 biofilm reactors units, or more, must be operated in series. Based on these results, it was concluded that concentrated CO 2 streams and plug flow behavior of the gaseous phase over the biofilm surface are essential for high productivity and CO 2 utilization efficiency. Biotechnol. Bioeng. 2017;114: 769-776. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  7. Effect of an enzymatic treatment with cellulase and mannanase on the structural properties of Nannochloropsis microalgae.

    Science.gov (United States)

    Maffei, Gianluca; Bracciale, Maria Paola; Broggi, Alessandra; Zuorro, Antonio; Santarelli, Maria Laura; Lavecchia, Roberto

    2018-02-01

    The effects of an enzymatic treatment with cellulase and mannanase on the properties of marine microalgae Nannochloropsis sp. were investigated. The combined use of these enzymes synergistically promoted the recovery of lipids from the microalgae, increasing the extraction yield from 40.8 to over 73%. Untreated and enzymatically treated microalgae were characterized by chemical analysis and by TGA/DTG, FTIR, XRD and SEM. Significant changes were observed in the chemical composition and thermal behavior of the microalgae. The enzymatic treatment also resulted in an increase of the crystalline-to-amorphous cellulose ratio. SEM images revealed dramatic changes in cell morphology, extensive cell damage and release of intracellular material. Overall, the results obtained indicate that the enzymes used are capable of disrupting the microalgal cell wall and that a combination of common analytical techniques can be used to assess the enzyme-induced damage. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Resistant biomacromolecules in five marine microalgae of the classes Eustigmatophyceae and Chlorophyceae: Geochemical implications

    NARCIS (Netherlands)

    Sinninghe Damsté, J.S.; Gelin, F.; Boogers, I.; Noordeloos, A.A.M.; Riegman, R.; Leeuw, J.W. de

    1997-01-01

    Non-hydrolysable macromolecular constituents (i.e. algaenans) were isolated from two out of seven marine microalgae investigated. Nannochloropsis salina and Nannochloropsis sp. from the class of Eustigmatophyceae produce highly aliphatic algaenans. Flash pyrolysis and chemical degradations with HI

  9. Thermogravimetric analysis of co-combustion between microalgae and textile dyeing sludge.

    Science.gov (United States)

    Peng, Xiaowei; Ma, Xiaoqian; Xu, Zhibin

    2015-03-01

    The synergistic interaction and kinetics of microalgae, textile dyeing sludge and their blends were investigated under combustion condition by thermogravimetric analysis. The textile dyeing sludge was blended with microalgae in the range of 10-90wt.% to investigate their co-combustion behavior. Results showed that the synergistic interaction between microalgae and textile dyeing sludge improved the char catalytic effect and alkali metals melt-induced effect on the decomposition of textile dyeing sludge residue at high temperature of 530-800°C. As the heating rate increasing, the entire combustion process was delayed but the combustion intensity was enhanced. The lowest average activation energy was obtained when the percentage of microalgae was 60%, which was 227.1kJ/mol by OFW and 227.4kJ/mol by KAS, respectively. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Microalgae to biofuels: life cycle impacts of methane production of anaerobically digested lipid extracted algae.

    Science.gov (United States)

    Quinn, Jason C; Hanif, Asma; Sharvelle, Sybil; Bradley, Thomas H

    2014-11-01

    This study presents experimental measurements of the biochemical methane production for whole and lipid extracted Nannochloropsis salina. Results show whole microalgae produced 430 cm(3)-CH4 g-volatile solids(-1) (g-VS) (σ=60), 3 times more methane than was produced by the LEA, 140 cm(3)-CH4 g-VS(-1) (σ=30). Results illustrate current anaerobic modeling efforts in microalgae to biofuel assessments are not reflecting the impact of lipid removal. On a systems level, the overestimation of methane production is shown to positively skew the environmental impact of the microalgae to biofuels process. Discussion focuses on a comparison results to those of previous anaerobic digestion studies and quantifies the corresponding change in greenhouse gas emissions of the microalgae to biofuels process based on results from this study. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Molecular characterization of CO2sequestration and assimilation in microalgae and its biotechnological applications.

    Science.gov (United States)

    Zhu, Baojun; Chen, Gu; Cao, Xupeng; Wei, Dong

    2017-11-01

    Microalgae are renewable feedstock for sustainable biofuel production, cell factory for valuable chemicals and promising in alleviation of greenhouse gas CO 2 . However, the carbon assimilation capacity is still the bottleneck for higher productivity. Molecular characterization of CO 2 sequestration and assimilation in microalgae has advanced in the past few years and are reviewed here. In some cyanobacteria, genes for 2-oxoglytarate dehydrogenase was replaced by four alternative mechanisms to fulfill TCA cycle. In green algae Coccomyxa subellipsoidea C-169, alternative carbon assimilation pathway was upregulated under high CO 2 conditions. These advances thus provide new insights and new targets for accelerating CO 2 sequestration rate and enhancing bioproduct synthesis in microalgae. When integrated with conventional parameter optimization, molecular approach for microalgae modification targeting at different levels is promising in generating value-added chemicals from green algae and cyanobacteria efficiently in the near future. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. A Saponification Method for Chlorophyll Removal from Microalgae Biomass as Oil Feedstock

    Directory of Open Access Journals (Sweden)

    Tao Li

    2016-09-01

    Full Text Available Microalgae oil is an optimal feedstock for nutraceutical, pharmaceutical and biodiesel production, but its high levels of chlorophyll limit its large-scale application. To date, few effective approaches have been developed to remove chlorophyll from microalgae oil. The main purpose of this study was to present a preprocessing method of algae oil feedstock (Scenedesmus to remove chlorophyll by saponification. The results showed that 96% of chlorophyll in biomass was removed. High quality orange transparent oil could be extracted from the chlorophyll reduced biomass. Specifically, the proportion of neutral lipids and saturation levels of fatty acids increased, and the pigments composition became carotenoids-based. The critical parameters of chlorophyll reduced biodiesel conformed to the standards of the USA, China and EU. Sodium copper chlorophyllin could be prepared from the bleaching effluent. The results presented herein offer a useful pathway to improve the quality of microalgae oil and reduce the cost of microalgae biodiesel.

  13. Comparative life cycle assessment of real pilot reactors for microalgae cultivation in different seasons

    NARCIS (Netherlands)

    Pérez-López, Paula; Vree, de Jeroen H.; Feijoo, Gumersindo; Bosma, Rouke; Barbosa, Maria J.; Moreira, María Teresa; Wijffels, René H.; Boxtel, van Anton J.B.; Kleinegris, Dorinde M.M.

    2017-01-01

    Microalgae are promising natural resources for biofuels, chemical, food and feed products. Besides their economic potential, the environmental sustainability must be examined. Cultivation has a significant environmental impact that depends on reactor selection and operating conditions. To

  14. Review of Microalgae Harvesting via Co-Pelletization with Filamentous Fungus

    Directory of Open Access Journals (Sweden)

    Bo Hu

    2013-11-01

    Full Text Available Cultivation of microalgae to utilize CO2 and nutrients in the wastewater to generate biofuel products is a promising research objective. However, the process faces tremendous technical difficulties, especially the harvest of microalgae cells, an economically challenging step. Several researchers recently reported co-culturing of filamentous fungi with microalgae so that microalgae cells can be co-pelletized in order to facilitate the cell harvest. This algae pelletization via the filamentous fungi represents an innovative approach to address both the cost and sustainability issues in algae biofuel production and also has potential with direct commercial applications. This paper reviews the current research status in this area and some possible drawbacks of this method in order to provide some possible directions for the future research.

  15. Water use and its recycling in microalgae cultivation for biofuel application.

    Science.gov (United States)

    Farooq, Wasif; Suh, William I; Park, Min S; Yang, Ji-Won

    2015-05-01

    Microalgal biofuels are not yet economically viable due to high material and energy costs associated with production process. Microalgae cultivation is a water-intensive process compared to other downstream processes for biodiesel production. Various studies found that the production of 1 L of microalgal biodiesel requires approximately 3000 L of water. Water recycling in microalgae cultivation is desirable not only to reduce the water demand, but it also improves the economic feasibility of algal biofuels as due to nutrients and energy savings. This review highlights recently published studies on microalgae water demand and water recycling in microalgae cultivation. Strategies to reduce water footprint for microalgal cultivation, advantages and disadvantages of water recycling, and approaches to mitigate the negative effects of water reuse within the context of water and energy saving are also discussed. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. A state of the art of metabolic networks of unicellular microalgae and cyanobacteria for biofuel production.

    Science.gov (United States)

    Baroukh, Caroline; Muñoz-Tamayo, Rafael; Steyer, Jean-Philippe; Bernard, Olivier

    2015-07-01

    The most promising and yet challenging application of microalgae and cyanobacteria is the production of renewable energy: biodiesel from microalgae triacylglycerols and bioethanol from cyanobacteria carbohydrates. A thorough understanding of microalgal and cyanobacterial metabolism is necessary to master and optimize biofuel production yields. To this end, systems biology and metabolic modeling have proven to be very efficient tools if supported by an accurate knowledge of the metabolic network. However, unlike heterotrophic microorganisms that utilize the same substrate for energy and as carbon source, microalgae and cyanobacteria require light for energy and inorganic carbon (CO2 or bicarbonate) as carbon source. This double specificity, together with the complex mechanisms of light capture, makes the representation of metabolic network nonstandard. Here, we review the existing metabolic networks of photoautotrophic microalgae and cyanobacteria. We highlight how these networks have been useful for gaining insight on photoautotrophic metabolism. Copyright © 2015 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

  17. Phytohormones and Effects on Growth and Metabolites of Microalgae: A Review

    Directory of Open Access Journals (Sweden)

    Xingfeng Han

    2018-04-01

    Full Text Available Microalgae cultivation is booming in agriculture, aquaculture, and bioenergy sectors. A wide range of bioactive compounds with attractive properties can be produced with microalgae, including pigments, vitamins, proteins, carbohydrates, and lipids. The biofuel yields from microalgae can exceed the yields obtained with energy crops by 10–100 times. Therefore, such cultivation is promising for the regulation of the biosynthesis of microalagae with phytohormones, which can enhance the production of high-valued bioproducts. This review reports the effect of auxins, abscisic acid, cytokinins, gibberellins, and ethylene on microalgal growth and metabolites, as well as the crosstalk of different phytohormones. The use of phytohormones is also promising because it can also reduce the inputs necessary to grow the selected microalgae and maximize the yields.

  18. A Verhulst model for microalgae Botryococcus sp. growth and nutrient removal in wastewater

    Science.gov (United States)

    Jamaian, Siti Suhana; Bakeri, Noorhadila Mohd; Sunar, Norshuhaila Mohamed; Gani, Paran

    2017-08-01

    Microalgae Botryococcus sp. is a colonial green alga found in lakes and reservoirs in Malaysia. Previous studies reported that the potential of Botryococcus sp. photosynthesis as a source of fuel. The Botryococcus sp. contains hydrocarbon up to 75% of dry weight, which can be converted into petrol, diesel or turbine fuel or other liquid or gaseous hydrocarbons. Recently, an experimental study was conducted on phycoremediation technology for wastewater using Botryococcus sp. The phycoremediation technology is useful to remove the excess of nutrients such as nitrogen, phosphorus and also have the ability to remove various pollutants from wastewater. This research implements the Verhulst model to estimate the nutrient removal by microalgae Botryococcus sp. from the wastewater. This model has been validated with the experiments of microalgae Botryococcus sp. grown in domestic and palm oil wastewater. The results suggested that microalgae Botryococcus sp. could be cultured in domestic and palm oil wastewater while nutrients are reduced from these wastewaters.

  19. Microalgae harvesting and cell disruption: a preliminary evaluation of the technology electroflotation by alternating current.

    Science.gov (United States)

    de Carvalho Neto, Riamburgo Gomes; do Nascimento, José Gilmar da Silva; Costa, Mayara Carantino; Lopes, Alexandre Colzi; Abdala Neto, Eliezer Fares; Filho, César Rossas Mota; Dos Santos, André Bezerra

    2014-01-01

    Some species of microalgae have high productivity and lipid content, which makes them good candidates for biodiesel production. Biomass separation and cell disruption are important steps in biodiesel production from microalgae. In this work, we explored the fundamentals of electroflotation by alternating current (EFAC) with non-consumable electrodes to simultaneously harvest microalgae and disrupt cells from mixed microalgae obtained from waste stabilization ponds. The harvesting efficiency was evaluated using chlorophyll-a and turbidity, which reached removals of 99% and 95%, respectively, during a batch time of 140 min. Cell disruption was evaluated using lipid extraction, and the best results were achieved with a batch time of 140 min, which resulted in a 14% yield. Therefore, EFAC was shown to be an attractive potential technology for simultaneous microalgal harvesting and cell disruption.

  20. Bio-gasification of post transesterified microalgae residues: A route to improving overall process renewabilities

    DEFF Research Database (Denmark)

    Ehimen, Ehiazesebhor Augustine

    Using results from experiments and process modelling tools, a renewability assessment was carried out for the use of the conventional and in-situ transesterification processes for a large scale microalgae biodiesel production. In a present day scenario, all the transesterification processes were...... shown to be non-renewable. The process renewability of biodiesel production from microalgae was found to significantly improve with the use of renewable electricity, reacting alcohols from biomass fermentation and process heating and biomass drying using heat from wood pellet combustion or heat pump...... technology. The anaerobic digestion of the microalgae residues to generate methane from was further seen to lead to positive renewabilities for the considered microalgae-biodiesel processes....