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Consumption and feeding preference of Echinogammarus marinus on two different algae: fucus vesiculosus and Ulva intestinalis

Martins, Irene; Leite, Nuno; Constantino, Emanuel
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.92%
Echinogammarus marinus constitutes the most abundant amphipod species in Fucus spp. assemblages from many North Atlantic estuaries. However, there are some doubts about the real use of fucoids by the amphipod. Whilst some studies report the ingestion of Fucus vesiculosus by E. marinus, others suggest that the amphipod preference for fucoids is mostly related to sheltering rather than feeding, due to the high phlorotannin content of brown algae. The purpose of the present work was to disentangle this issue by checking the consumption rate and feeding preference of E. marinus on F. vesiculosus, its preferential habitat, and on Ulva intestinalis, a green algae abundant in the Mondego estuary (Western Coast of Portugal) and usually considered as highly palatable for herbivores. In a 2-stage laboratorial setup, fresh disks of the two types of algae were offered to E. marinus for three days. Consumption rates were estimated from differences between algal and animal initial and final fresh weights using a control correction factor, while preference was tested by differences in algal consumption rates when no choice was offered (stage 1) and when the two algae were offered simultaneously (stage 2). Results showed that E. marinus effectively consumed fresh F. vesiculosus in much higher amounts than U. intestinalis and significantly preferred to consume F. vesiculosus over U. intestinalis. Therefore...

Lipid, fatty acid, protein, amino acid and ash contents in four Brazilian red algae species

GRESSLER, Vanessa; YOKOYA, Nair Sumie; FUJII, Mutue Toyota; COLEPICOLO, Pio; MANCINI FILHO, Jorge; TORRES, Rosangela Pavan; PINTO, Ernani
Fonte: ELSEVIER SCI LTD Publicador: ELSEVIER SCI LTD
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.86%
Four species of marine benthic algae (Laurencia filiformis, L. intricata, Gracilaria domingensis and G. birdiae) that belong to the phylum Rhodophyta were collected in Espirito Santo State, Brazil and investigated concerning their biochemical composition (fatty acid, total lipid, soluble proteins, amino acid and ash). The total content of lipid (% dry weight) ranged from 1.1% to 6.2%: fatty acid from 0.7% to 1.0%: soluble protein from 4.6% to 18.3%, amino acid from 6.7% to 11.3% and ash from 22.5% to 38.4%. judging from their composition, the four species of algae appear to be potential sources of dietary proteins, amino acids, lipids and essential fatty acids for humans and animals. (C) 2009 Elsevier Ltd. All rights reserved.; FAPESP (Fundacao de Amparo a Pesquisa do Estado de Sao Paulo); Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); CAPES (Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); CNPq (Conselho Nacional de Desenvolvimento Cientifico e Tecnologico); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Efeito de cianobactérias e algas eucarióticas na resistência de plantas de fumo contra o Tobacco mosaic virus (TMV); Effect of cyanobacteria and eukaryotic algae on the resistance of tobacco plants against Tobacco mosaic virus

Beltrame, André Boldrin
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 26/01/2006 PT
Relevância na Pesquisa
37%
As algas produzem uma grande diversidade de compostos com atividade biológica, inclusive que agem diretamente sobre vírus ou como indutores de fitoalexinas. Em vista disso, foi investigada a redução de sintomas causados por Tobacco mosaic vírus (TMV) em plantas de fumo tratadas com cianobactérias ou algas eucarióticas, além de se tentar elucidar o modo de ação das algas no patossistema estudado. Quando as plantas de fumo foram tratadas dois dias antes da inoculação, foi verificado que suspensões dos isolados 004/02, 008/02, 061/02, Anabaena sp. e Nostoc sp. 61, bem como as preparações do conteúdo intracelular do isolado 004/02 (4 C) e do filtrado do meio de cultivo do isolado 061/02 (61 M) apresentaram efeito na redução dos sintomas de TMV em plantas de fumo, cultivar TNN. Além disso, foi estudado o efeito direto das algas sobre as partículas de vírus. Os resultados mostraram que os isolados Anabaena sp., Nostoc sp. 21, Nostoc sp. 61 e 090/02 apresentam compostos que agem diretamente sobre o TMV. Para tentar elucidar o mecanismo de ação das algas no patossistema estudado, diversos parâmetros bioquímicos foram investigados. Foi detectado que a preparação 4 C aumentou a atividade de peroxidases e que todos os tratamentos analizados reduziram a atividade de β-1...

Modulação dos níveis de pigmentos e ácidos graxos em algas marinhas: função dos carotenóides e efeitos do estresse ambiental; Modulation of fatty acids and pigments in marine algae: function of carotenoids and environment stress

Pinto Junior, Ernani
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 02/08/2002 PT
Relevância na Pesquisa
36.92%
O estresse ambiental sobre algas marinhas pode ser causado por poluentes, ausência de nutrientes, variação da temperatura ou da intensidade luminosa. Embora vários grupos estudem os efeitos do estresse ambiental sobre a ecologia de animais marinhos, nos últimos anos, contudo, poucos pesquisadores têm investigado o seu efeito sobre a fisiologia das algas marinhas, sobretudo sobre a biossíntese e função de carotenóides e ácidos graxos. Deste modo, foram abordados experimentalmente a atividade antioxidante in vitro de alguns carotenóides encontrados em algas (determinação da constante de supressão (KQ) de oxigênio singlete (02 (1Δg)) e redução da lipoperoxidação em lipossomos incorporados com carotenóides) bem como a monitoração da biossíntese de pigmentos e os níveis de ácidos graxos em algumas espécies de algas cultivadas em situações de estresse ambiental, como exposição a metais pesados (Gracilaria tenuistipitata e Lingulodinium polyedrum), alta densidade populacional (Amphidinium cartareae, Nitzschia microcephala, Lingulodinium polyedrum, Minutocellus polymorphus e Tetraselmis gracilis), e intensidade luminosa (Lingulodinium polyedrum). Ainda, nas algas expostas a estas condições adversas, parâmetros de estresse oxidativo e indicadores enzimáticos do metabolismo oxidativo foram medidos...

Biocatalisadores de origem marinha (algas, bactérias e fungos) para redução estereosseletiva de cetonas; Biocatalysts from marine origin (algae, bacteria and fungi) for stereoselectivy reduction of ketones

Mouad, Ana Maria
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 10/09/2009 PT
Relevância na Pesquisa
37.08%
Neste trabalho foram realizadas reações de redução de cetonas empregando diferentes organismos marinhos como biocatalisadores (algas, fungos e bactérias). Nas triagens foram utilizados derivados de acetofenonas (o-iodoacetofenona, m-iodoacetofenona, p-iodoacetofenona, o-fluoracetofenona, o-cloroacetofenona, o-bromoacetofenona, o-nitroacetofenona) e duas cetonas 1,3-dicarboniladas: a 4,4,4-triflúor-1-(furan-2-il)butano-1,3-diona e a 4,4,4-triflúor-1-(naftalen-2-il)butano-1,3-diona. As reações com as algas marinhas Bostrychia tenella e a Bostrychia radicans levaram aos álcoois com excelentes seletividades (ee >98%), contudo, obtiveram-se baixas conversões. Foram isoladas as bactérias Bt-01 (B. tenella) e Bt-02 (B. radicans), as quais catalisaram as reduções das acetofenonas com resultados similares aos obtidos com as algas. Os fungos (Br-09, Br-23, Br-27, Br-61) isolados da alga B. radicans reduziram as acetofenonas com boas seletividades e conversões. Ainda, reações de redução das acetofenonas com quatro linhagens de fungos isolados da alga Sargassum sp (SMA2-C, SMA2-8, SMA2-58, SGPY-41) levaram a obtenção dos respectivos álcoois com diferentes conversões e seletividades. As reduções das cetonas 1,3-dicarboniladas foram realizadas com as algas B. tenella e B. radicans...

A temática algas na formação continuada de professores de Biologia: uma experiência na Educação a Distância; The theme algae in the continuing formation of Biology's teachers: an experience in Distance Education

Lima, Thierry Faria
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 23/10/2014 PT
Relevância na Pesquisa
37.13%
Diante das demandas do cenário da Educação atual, incluindo o Ensino de Biologia, professores em exercício transformam-se novamente em aprendizes e sua qualificação pedagógica torna-se urgente e necessária. Uma das estratégias atualmente adotadas na formação continuada refere-se ao oferecimento de cursos em Educação a Distância. A ação dos professores sempre é permeada por diversos saberes docentes, que devem ser abordados nesses cursos de formação. Pensando-se nos saberes disciplinares, ao analisarmos documentos orientadores como a Proposta Curricular do Estado de São Paulo (PCESP) - Ensino Médio, percebemos que a abordagem do tema algas é problemática. Diante desse panorama, o presente trabalho visou contribuir para a ampliação do conhecimento sobre a abordagem das algas na formação continuada de professores de Biologia na modalidade Educação a Distância. Para tanto, focamos 36 profissionais participantes em um curso de especialização docente (Curso de Especialização para Docentes em Biologia, EspBio) oferecido pela Rede São Paulo de Formação Docente (Redefor). Tivemos como um dos objetivos específicos elaborar recursos didáticos sobre as algas, abordando três vertentes temáticas principais: algas e cotidiano (incluindo biodiversidade e importância socioeconômica)...

New drugs with antiprotozoal activity from marine algae: a review

Torres, Fábio A.e.; Passalacqua, Thais G.; Velásquez, Angela M.a.; Souza, Rodrigo A. De; Colepicolo, Pio; Graminha, Márcia A.s.
Fonte: Sociedade Brasileira de Farmacognosia Publicador: Sociedade Brasileira de Farmacognosia
Tipo: Artigo de Revista Científica Formato: 265-276
ENG
Relevância na Pesquisa
36.97%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); The use of indigenous or remote popular knowledge to identify new drugs against diseases or infections is a well-known approach in medicine. The inhabitants of coastal regions are known to prepare algae extracts for the treatment of disorders and ailments such as wounds, fever and stomach aches, as for the prevention of arrhythmia. Recent trends in drug research from natural sources have indicated that marine algae are a promising source of novel biochemically active compounds, especially with antiprotozoal activity. Algae survive in a competitive environment and, therefore, developed defense strategies that have resulted in a significant level of chemical structural diversity in various metabolic pathways. The exploration of these organisms for pharmaceutical and medical purposes has provided important chemical candidates for the discovery of new agents against neglected tropical diseases, stimulating the use of sophisticated physical techniques. This current review describes the main substances biosynthesized by benthic marine algae with activity against Leishmania spp....

Calcium-phosphate derived from mineralized algae for bone tissue engineering applications

Oliveira, Joaquim M.; Grech, Jessica M. R.; Leonor, I. B.; Mano, J. F.; Reis, R. L.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Publicado em //2007 ENG
Relevância na Pesquisa
36.92%
In this work, several routes are described towards obtaining pure inorganic phases derived from Coralline officinallis red algae. The scanning electron microscopy studies have shown that it becomes possible not only to eliminate the undesired organic phase, but also to preserve or tailor the red algae typical microporosity. X-ray diffraction analysis was used to investigate the phase content of the red algae before and after performing the different treatment routes. Hydroxyapatite nanocrystallites were obtained after converting the coralline calcium carbonate skeleton by means of combining thermal and chemical routes. These results were confirmed by Fourier transform infra-red spectroscopic analysis. The processing routes herein described are very promising in order to design bioceramics of algae origin that might find useful applications as bone fillers and tissue engineering scaffolds.

Contribution to the taxonomy and ecology of the Azorean benthic marine algae

Neto, Ana I.
Fonte: John Wiley and Sons Publicador: John Wiley and Sons
Tipo: Artigo de Revista Científica
Publicado em 01/05/1992 ENG
Relevância na Pesquisa
36.92%
Copyright © 1992, John Wiley and Sons.; Algal zonation patterns were studied in two sites (Caloura, south coast and Ribeirinha, north coast) of the island of São Miguel, Azores. At each site two stations were studied and the transects revealed the occurrence of two distinct and well established algal zones. In the first zone, daily immersed and emersed by the tide, the algae were growing in a dense and, short tangle forming a mat, referred to as algal turf. In the second zone, which was wet most of the time, the algae were larger and frondose. A list of the species of benthic marine algae occurring on the algal turf of each station is given. Of the total of 47 species found, eight are new for the Azores and another 13 species recorded for the first time for São Miguel. Gigartina acicularis (Roth) Lamouroux and articulate coralline algae (Corallina oficinalis Linnaeus and Jania spp.) were the more common species. Seasonal variation of the algal turf was studied and related to mean monthly values of air and sea water temperatures, insolation and hours of light. The zonation patterns and composition of algal species were compared with those from other open rocky shores.

New drugs with antiprotozoal activity from marine algae: a review

Torres,Fábio A.E.; Passalacqua,Thais G.; Velásquez,Angela M.A.; Souza,Rodrigo A. de; Colepicolo,Pio; Graminha,Márcia A.S.
Fonte: Sociedade Brasileira de Farmacognosia Publicador: Sociedade Brasileira de Farmacognosia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2014 EN
Relevância na Pesquisa
36.97%
The use of indigenous or remote popular knowledge to identify new drugs against diseases or infections is a well-known approach in medicine. The inhabitants of coastal regions are known to prepare algae extracts for the treatment of disorders and ailments such as wounds, fever and stomach aches, as for the prevention of arrhythmia. Recent trends in drug research from natural sources have indicated that marine algae are a promising source of novel biochemically active compounds, especially with antiprotozoal activity. Algae survive in a competitive environment and, therefore, developed defense strategies that have resulted in a significant level of chemical structural diversity in various metabolic pathways. The exploration of these organisms for pharmaceutical and medical purposes has provided important chemical candidates for the discovery of new agents against neglected tropical diseases, stimulating the use of sophisticated physical techniques. This current review describes the main substances biosynthesized by benthic marine algae with activity against Leishmania spp., Trypanosoma cruzi and Trypanosoma brucei; the causative agents of leishmaniasis, Chagas disease and African trypanosomiasis, respectively. Emphasis is given to secondary metabolites and crude extracts prepared from marine algae.

Are anti-fouling effects in coralline algae species specific?

Villas Bôas,Alexandre Bigio; Figueiredo,Marcia A. de O.
Fonte: Universidade de São Paulo, Instituto Oceanográfico Publicador: Universidade de São Paulo, Instituto Oceanográfico
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2004 EN
Relevância na Pesquisa
37%
The crustose coralline algae are susceptible to be covered by other algae, which in turn can be affected by anti-fouling effects. In this study the hypothesis tested was that these algae can inhibit the growth of epiphytes in a species specific way. In the laboratory, propagules of Sargassum furcatum and Ulva fasciata were liberated and cultivated on pieces of coralline algae and slide covers (controls) and their survival and growth were compared. Spongites and Hydrolithon significantly inhibited the growth of U. fasciata but not Sargassum. In the field, pieces of three species of live and dead coralline algae and their copies in epoxy putty discs were fixed on the rock. After one month epiphytic algae were identified and their dry mass quantified. Lithophyllum did not affect the epiphyte growth. In contrast Spongites and an unidentified coralline significantly inhibited the growth of Enteromorpha spp., Ulva fasciata and Hincksia mitchelliae. Colpomenia sinuosa was absent on all living crusts, but present on controls. Results show that the epiphyte-host relation depends on the species that are interacting. The sloughing of superficial cells of coralline crusts points to the possible action of physical anti-fouling effect, though a chemical one is not rejected.

Physical disturbance by kelp abrades erect algae from the understorey

Irving, A.; Connell, S.
Fonte: Inter-research Publicador: Inter-research
Tipo: Artigo de Revista Científica
Publicado em //2006 EN
Relevância na Pesquisa
36.97%
Positive and negative interactions among organisms are key determinants of pattern in the distribution and abundance of many species. Beneath subtidal canopies of kelp Ecklonia radiata (Laminariales), we observed sparse covers of erect algae (articulated coralline algae and filamentous turf-forming algae) that formed extensive covers where canopies were absent. Moreover, articulated corallines occurred in greater abundance beneath canopies of E. radiata mixed with canopy-forming species of Fucales than beneath monospecific canopies of E. radiata. We experimentally tested the hypotheses that (1) canopies negatively affect the abundance of articulated corallines and filamentous turfs, (2) physical abrasion of the substratum by canopies contributes to such negative effects, and (3) the effect of abrasion on articulated corallines is greater beneath monospecific canopies than mixed-species canopies, but the effect on filamentous turfs does not differ between types of canopy. Experiments revealed large negative effects of canopies on the abundance of articulated corallines and filamentous turfs, to which abrasion made a substantial contribution (~54 to 67% for articulated coralline and ~58% for filamentous turf). Moreover, the intensity of abrasion was greater beneath monospecific than mixed-species canopies...

Faecal indicator bacteria monitoring in blue-green algae contaminated water

Zhou, JINGJING
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN; EN
Relevância na Pesquisa
36.97%
Abstract Due to enhanced human and climatically-driven environmental changes, numerous water bodies including the Great Lakes area have seen increased harmful algal blooms (HABs) (including those caused by blue-green algae) in the past few decades. HABs affect the ecological integrity of the affected water by disrupting or altering the biological communities, bringing more challenges to water-quality monitoring and sustainable water management. Faecal indicator bacteria (FIB) monitoring for detection of possible microbial and pathogen contamination is a significant water-management practice, with implications for water resource sustainability. Work in this thesis focuses on HAB impact on faecal indicator bacteria survival and thus the use of FIB for indicating microbial contamination. To serve this purpose, microcosms that contain the representative algae and indicator bacteria were established to explore the algae-bacteria dynamics at laboratory scale. Two species of Microcystis (M. smithii and M. aeruginosa) and four lab strains of E. coli (ATCC 25922, 8739, 51813, and 11775) were used. The sample water was collected regularly for Microcystis and E. coli screening. Microcystis was shown to dramatically reduce E. coli survival in the microcosms. Three possible factors contributing to the observed algae-E. coli dynamics...

Antioxidant response and caulerpenyne production of the alien Caulerpa taxifolia (Vahl) epiphytized by the invasive algae Lophocladia lallemandii (Montagne)

Box Centeno, Antonio; Sureda, Antoni; Terrados, Jorge; Pons, Antoni; Deudero Company, María de la Salud
Fonte: Elsevier Publicador: Elsevier
Tipo: Artículo Formato: 918459 bytes; application/pdf
ENG
Relevância na Pesquisa
36.97%
5 pages, 4 figures, 1 table.-- Printed version published on Sep 12, 2008.; Invasive algae alter the structure and function of ecosystems. The red algae Lophocladia lallemandii grows in the West Mediterranean epiphyting the green algae Caulerpa taxifolia, another invasive alga. Our aim was to determine whether the invasive algae Lophocladia, recently introduced in the West Mediterranean, induces oxidative stress and an antioxidant response in Caulerpa taxifolia. We measured the caulerpenyne production, the activities of antioxidant enzymes and the levels of markers of lipid peroxidation in Caulerpa taxifolia. Caulerpenyne concentration was significantly higher in Caulerpa taxifolia epiphytized by Lophocladia. End-products of lipid peroxidation -malondialdehyde (MDA) and 4-hydroxinonenal (4-HNE)- were significantly increased in Caulerpa taxifolia samples from the station with Lophocladia. Antioxidant enzyme activities -catalase and superoxide dismutase (SOD)-, as well as H2O2 production significantly increased in the Lophocladia station compared to the control station. The activities of catalase and SOD determined in Lophocladia lallemandii showed no significant differences between Lophocladia living alone and Lophocladia epiphytating Caulerpa taxifolia. Caulerpa taxifolia epiphytized by Lophocladia lallemandii responded by increasing the caulerpenyne and H2O2 production and the antioxidant enzymes activities as a defensive mechanism against the new invasive algae.; This work was supported by the projects “Expansión de Caulerpa prolifera...

Are anti-fouling effects in coralline algae species specific?

Villas Bôas, Alexandre Bigio; Figueiredo, Marcia A. de O.
Fonte: Universidade de São Paulo. Instituto Oceanográfico Publicador: Universidade de São Paulo. Instituto Oceanográfico
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; Peer-reviewed Article Formato: application/pdf
Publicado em 01/03/2004 ENG
Relevância na Pesquisa
37%
The crustose coralline algae are susceptible to be covered by other algae, which in turn can be affected by anti-fouling effects. In this study the hypothesis tested was that these algae can inhibit the growth of epiphytes in a species specific way. In the laboratory, propagules of Sargassum furcatum and Ulva fasciata were liberated and cultivated on pieces of coralline algae and slide covers (controls) and their survival and growth were compared. Spongites and Hydrolithon significantly inhibited the growth of U. fasciata but not Sargassum. In the field, pieces of three species of live and dead coralline algae and their copies in epoxy putty discs were fixed on the rock. After one month epiphytic algae were identified and their dry mass quantified. Lithophyllum did not affect the epiphyte growth. In contrast Spongites and an unidentified coralline significantly inhibited the growth of Enteromorpha spp., Ulva fasciata and Hincksia mitchelliae. Colpomenia sinuosa was absent on all living crusts, but present on controls. Results show that the epiphyte-host relation depends on the species that are interacting. The sloughing of superficial cells of coralline crusts points to the possible action of physical anti-fouling effect, though a chemical one is not rejected.; As algas calcárias crostosas são susceptíveis ao recobrimento por outras algas...

Algae and Coal: Turning Pollution Into Prosperity

McNamara, Patrick
Fonte: Universidade Duke Publicador: Universidade Duke
Tipo: Masters' project Formato: 123002 bytes; application/msword
EN_US
Relevância na Pesquisa
36.97%
Algae have long been researched as a potential source of biodiesel and biofuel because of their quick growth rate, simple inputs and ability to grow under environments unsuitable for many other plants. Using a Monte Carlo simulation, this analysis examines the circumstances under which an algae farm might become profitable now and in the future. The use of CO2 from fossil fuels, specifically coal-fired power plants, is potentially valuable for both the utility and the algae farm because algae require large amounts of CO2 for their high growth rates. My results show that the success of algae farms in the United States is currently unprofitable in the short and mid-term (five to ten years). Moreover their long term profitability is heavily dependent on the system design, fuel prices, location, the existence and increase of prices being placed on air pollutants such as CO2 and NOX, as well as successive scientific breakthroughs under reasonable assumptions.

Scale-up of algae growth system to cleanse wastewater and produce oils for biodiesel production

Lannan, Eric
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
EN_US
Relevância na Pesquisa
36.92%
Biofuels are a currently a very hot topic with significant interest in both ethanol and biodiesel production. These fuels can be used in current internal combustion engines with little or no modification. Biodiesel can be produced from a variety of sources. One of the most promising sources is microalgae. In some species of algae, oil or lipids can account for as much as 70% of their total biomass. Unfortunately, the cost to produce biodiesel from algae is much too high to compete with petroleum-based fuels. To reduce the production cost of algae, wastewater has been discovered to be an excellent growth media. For this study, Chlorella sp., Scenedesmus sp., and Chlamydomonas sp. were selected to test their ability to grow on wastewater growth media while cleansing the water of contaminants and producing oil. Lab tests in 10L tanks showed that all three species grow well and provide excellent treatment of municipal wastewater by reduction of ammonia, nitrate, and phosphate at levels of 99%, 87%, and 99%, respectively. After successful lab tests, a 230L (60 gal.) pilot tank was constructed to demonstrate scalability of the growth system. Scenedesmus was selected for growth tests at the pilot scale. Six growth tests of one week each were conducted at two light levels and three temperatures to investigate the effects these parameters have on the growth rate and nutrient uptake. In the pilot scale tests...

Os florotaninos e fenóis de algas pardas (Phaeophyceae); Phlorotannins and phenols of brown algae (Phaeophyceae)

Pereira, Renato Crespo; Universidade Federal Fluminense; Yoneshigue-Valentin, Yocie; Instituto de Estudos do Mar Almirante Paulo Moreira (Marinha do Brasil); Teixeira, Valeria Laneuville; Universidade Federal Fluminense; Kelecom, Alphonse; Universidade Fe
Fonte: Universidade Federal de Santa Catarina Publicador: Universidade Federal de Santa Catarina
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; Formato: application/pdf
Publicado em 01/01/1989 POR
Relevância na Pesquisa
36.97%
O floroglucinol e seus derivados, assim como outras substâncias fenólicas são abundantes em algas pardas. Apresentando estruturas bastante diversificadas, ampla atividade biológica e grande concentração em diferentes espécies, demonstram relevantes papeis fisio1ógicos e ecológicos no meio marinho, contribuindo para a maior sobrevivência das algas pardas em vias gerais. Atualmente são conhecidos lO5 metabólitos pertencentes a diferentes classes e presentes em 49 espécies de algas pardas, compreendendo o floroglucinol, 4 fucóis, 8 floretóis, 30 fuco-floretóis, 17 fu-halóis, 14 ecóis, 4 alquil-fenóis, 13 acil-fenóis, 2 halo-floroglucinol, 3 halo-floretóis, 2 halo-ecóis, 3 alcoóis benzílicos, 2 prenil-toluóis e 2 derivados sulfatados. Estes metabólitos foram classificados através de vias biossintéticas originadas no precursor floroglucinol. A ampla distribuição desses derivados fenólicos nas algas pardas sugere a sua utilização como prováveis marcadores taxonômicos e filogenéticos da classe Phaeophyceae, podendo fornecer importantes contribuições para a elucidação dos limites de separação das algas deste grupo.; Phlorotannins and their derivatives, as well as other phenolic substances are abundant in brown algae. These substances present highly diversified structures and broad biological activity spectrum. Their high concentration in a number of species demonstrates relevant physiological and ecological roles in marine environments. This fact contributes to the important survival of brown algae in these environments. Presently...

Determination of the distribution of shallow-water seagrass and drift algae communities with acoustic seafloor discrimination

Riegl,B; Moyer,R.P; Morris,L; Virnstein,R; Dodge,R.E
Fonte: Revista de Biología Tropical Publicador: Revista de Biología Tropical
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/05/2005 EN
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37%
The spatial distribution of seagrass and algae communities can be difficult to determine in large,shallow lagoon systems where high turbidity prevents the use of optical methods like aerial photography or satellite imagery.Further complications can arise when algae are not permanently attached to the substratum and drift with tides and currents.A study using acoustic seafloor discrimination was conducted in the Indian River Lagoon (Florida,USA)to determine the extent of drift algae and seagrass.Acoustic surveys using the QTC View V system based on 50 and 200 kHz transducers were conducted near Sebastian Inlet.Results indicate that areas of seagrass can be identified,and are mixed with a high abundance of drift algae.Nearest-neighbor extrapolation was used to fill in spaces between survey lines and thus obtain spatially cohesive maps.These maps were then ground-truthed using data from towed video and compared using confusion matrices.The maps showed a high level of agreement (60%)with the actual distribution of algae,however some confusion existed between bare sand and algae as well as seagrass.

The marine algae Sargassum spp. (Sargassaceae) as feed for sheep in tropical and subtropical regions

Marín,Alejandro; Casas-Valdez,Margarita; Carrillo,Silvia; Hernández,Hugo; Monroy,Alberto; Sanginés,Leonor; Pérez-Gil,Fernando
Fonte: Revista de Biología Tropical Publicador: Revista de Biología Tropical
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2009 EN
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The objective of this study was to evaluate Sargassum meal as feed for sheep through the measures of in vivo digestibility, dry matter degradability, pH, ammonia and volatile fatty acids in rumen. The Sargassum algae used in this experiment were collected at the end of spring, when they are more abundant, bigger, and have completed their reproductive cycle. Four tons (wet weigth) were collected manually from the intertidal zone of La Paz bay, Baja California Sur, Mexico. These algae were sun-dried and ground in a hammer mill to obtain the Sargassum meal. Four fistulated Pelibuey sheep, were fed daily with diets containing the marine algae (MA) at different levels (0, 10, 20 and 30 %), using a 4 x 4 Latin-square design experiment. Feed intake was not affected (p>0.05). Water consumption and urine excretion increased with MA (p<0.05; r²=0.54 and r²=0.74, respectively). In all treatments dry matter digestibility was of 74%-79%, and crude protein digestibility was of 85%-88%. Acid detergent fiber (59%-65%) and neutral detergent fiber (55%-66%) digestibility were greater in all treatments with MA. Ruminal pH was greater in all groups fed with MA (p<0.05). Ammonium concentration was not influenced (p>0.05) by MA. Ruminal volatile fatty acids decreased in all MA groups (p<0.05). The marine algae Sargassum spp. can be used as a feed supplement for sheep...