WorldWideScience

Sample records for microalgae euglena gracilis

  1. Improvement of kinetics, yield, and colloidal stability of biogenic gold nanoparticles using living cells of Euglena gracilis microalga

    Science.gov (United States)

    Dahoumane, Si Amar; Yéprémian, Claude; Djédiat, Chakib; Couté, Alain; Fiévet, Fernand; Coradin, Thibaud; Brayner, Roberta

    2016-03-01

    Recent years have witnessed a boom in the biosynthesis of a large variety of nanomaterials using different biological resources among which algae-based entities have been gaining much more attention within the community of material scientists worldwide. In our previously published findings, we explored some factors that governed the biofabrication of gold nanoparticles using living cultures of microalgae, such as the utilized microalgal genera, the phylum they belong to, and the impact of tetrachloroauric acid concentrations on the ability of these strains to perform the biosynthesis of gold nanoparticles once in contact with these cations. As a follow-up, we present in this paper an improvement of the features of bioproduced gold colloids using living cells of Euglena gracilis microalga when this species is grown under either mixotrophic or autotrophic conditions, i.e., exposed to light and grown in an organic carbon-enriched culture medium versus under autotrophic conditions. As an outcome to this alteration, the growth rate of this photosynthetic microorganism is multiplied 7-8 times when grown under mixotrophic conditions compared to autotrophic ones. Therefore, the yield, the kinetics, and the colloidal stability of the biosynthesized gold nanoparticles are dramatically enhanced. Moreover, the shape and the size of the as-produced nano-objects via this biological method are affected. In addition to round-shaped gold nanoparticles, particular shapes, such as triangles and hexagons, appear. These findings add up to the amassed knowledge toward the design of photobioreactors for the scalable and sustainable production of interesting nanomaterials.

  2. Improvement of kinetics, yield, and colloidal stability of biogenic gold nanoparticles using living cells of Euglena gracilis microalga

    Energy Technology Data Exchange (ETDEWEB)

    Dahoumane, Si Amar, E-mail: sa.dahoumane@gmail.com [Paris-Diderot University, Sorbonne Paris Cité, Interfaces, Traitements, Organisation et Dynamique des Systèmes (ITODYS), UMR 7086, CNRS (France); Yéprémian, Claude; Djédiat, Chakib; Couté, Alain [Muséum National d’Histoire Naturelle, Département RDDM, UMR 7245, Unité MCAM (France); Fiévet, Fernand [Paris-Diderot University, Sorbonne Paris Cité, Interfaces, Traitements, Organisation et Dynamique des Systèmes (ITODYS), UMR 7086, CNRS (France); Coradin, Thibaud, E-mail: thibaud.coradin@upmc.fr [UPMC—Paris 06, CNRS, Chimie de la Matière Condensée de Paris, Collège de France (France); Brayner, Roberta, E-mail: roberta.brayner@univ-paris-diderot.fr [Paris-Diderot University, Sorbonne Paris Cité, Interfaces, Traitements, Organisation et Dynamique des Systèmes (ITODYS), UMR 7086, CNRS (France)

    2016-03-15

    Recent years have witnessed a boom in the biosynthesis of a large variety of nanomaterials using different biological resources among which algae-based entities have been gaining much more attention within the community of material scientists worldwide. In our previously published findings, we explored some factors that governed the biofabrication of gold nanoparticles using living cultures of microalgae, such as the utilized microalgal genera, the phylum they belong to, and the impact of tetrachloroauric acid concentrations on the ability of these strains to perform the biosynthesis of gold nanoparticles once in contact with these cations. As a follow-up, we present in this paper an improvement of the features of bioproduced gold colloids using living cells of Euglena gracilis microalga when this species is grown under either mixotrophic or autotrophic conditions, i.e., exposed to light and grown in an organic carbon-enriched culture medium versus under autotrophic conditions. As an outcome to this alteration, the growth rate of this photosynthetic microorganism is multiplied 7–8 times when grown under mixotrophic conditions compared to autotrophic ones. Therefore, the yield, the kinetics, and the colloidal stability of the biosynthesized gold nanoparticles are dramatically enhanced. Moreover, the shape and the size of the as-produced nano-objects via this biological method are affected. In addition to round-shaped gold nanoparticles, particular shapes, such as triangles and hexagons, appear. These findings add up to the amassed knowledge toward the design of photobioreactors for the scalable and sustainable production of interesting nanomaterials.

  3. Exploring the glycans of Euglena gracilis

    DEFF Research Database (Denmark)

    O’Neill, Ellis C.; Kuhaudomlarp, Sakonwan; Rejzek, Martin

    2017-01-01

    Euglena gracilis is an alga of great biotechnological interest and extensive metabolic capacity, able to make high levels of bioactive compounds, such as polyunsaturated fatty acids, vitamins and β-glucan. Previous work has shown that Euglena expresses a wide range of carbohydrate-active enzymes,...

  4. Unexpectedly Streamlined Mitochondrial Genome of the Euglenozoan Euglena gracilis

    Czech Academy of Sciences Publication Activity Database

    Dobáková, Eva; Flegontov, Pavel; Skalický, Tomáš; Lukeš, Julius

    2015-01-01

    Roč. 7, č. 12 (2015), s. 3358-3367 ISSN 1759-6653 R&D Projects: GA ČR GA15-21974S Institutional support: RVO:60077344 Keywords : Euglena gracilis * mitochondrial genome * transcription * RNA editing Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 4.098, year: 2015

  5. High-speed stimulated Raman scattering microscopy for studying the metabolic diversity of motile Euglena gracilis

    Science.gov (United States)

    Suzuki, Y.; Wakisaka, Y.; Iwata, O.; Nakashima, A.; Ito, T.; Hirose, M.; Domon, R.; Sugawara, M.; Tsumura, N.; Watarai, H.; Shimobaba, T.; Suzuki, K.; Goda, K.; Ozeki, Y.

    2017-02-01

    Microalgae have been receiving great attention for their ability to produce biomaterials that are applicable for food supplements, drugs, biodegradable plastics, and biofuels. Among such microalgae, Euglena gracilis has become a popular species by virtue of its capability of accumulating useful metabolites including paramylon and lipids. In order to maximize the production of desired metabolites, it is essential to find ideal culturing conditions and to develop efficient methods for genetic transformation. To achieve this, understanding and controlling cell-to-cell variations in response to external stress is essential, with chemically specific analysis of microalgal cells including E. gracilis. However, conventional analytical tools such as fluorescence microscopy and spontaneous Raman scattering are not suitable for evaluation of diverse populations of motile microalgae, being restricted either by the requirement for fluorescent labels or a limited imaging speed, respectively. Here we demonstrate video-rate label-free metabolite imaging of live E. gracilis using stimulated Raman scattering (SRS) - an optical spectroscopic method for probing the vibrational signatures of molecules with orders of magnitude higher sensitivity than spontaneous Raman scattering. Our SRS's highspeed image acquisition (27 metabolite images per second) allows for population analysis of live E. gracilis cells cultured under nitrogen-deficiency - a technique for promoting the accumulation of paramylon and lipids within the cell body. Thus, our SRS system's fast imaging capability enables quantification and analysis of previously unresolvable cell-to-cell variations in the metabolite accumulation of large motile E. gracilis cell populations.

  6. Euglena gracilis Z and its carbohydrate storage substance relieve arthritis symptoms by modulating Th17 immunity.

    Directory of Open Access Journals (Sweden)

    Kengo Suzuki

    Full Text Available Euglena gracilis Z is a microorganism classified as a microalga and is used as a food or nutritional supplement. Paramylon, the carbohydrate storage substance of E. gracilis Z, is reported to affect the immunological system. This study evaluated the symptom-relieving effects of E. gracilis Z and paramylon in rheumatoid arthritis in a collagen-induced arthritis mouse model. The efficacy of both substances was assessed based on clinical arthritis signs, as well as cytokine (interleukin [IL]-17, IL-6, and interferon [IFN]-γ levels in lymphoid tissues. Additionally, the knee joints were harvested and histopathologically examined. The results showed that both substances reduced the transitional changes in the visual assessment score of arthritis symptoms compared with those in the control group, indicating their symptom-relieving effects on rheumatoid arthritis. Furthermore, E. gracilis Z and paramylon significantly reduced the secretion of the cytokines, IL-17, IL-6, and IFN-γ. The histopathological examination of the control group revealed edema, inflammation, cell hyperplasia, granulation tissue formation, fibrosis, and exudate in the synovial membrane, as well as pannus formation and articular cartilage destruction in the femoral trochlear groove. These changes were suppressed in both treatment groups. Particularly, the E. gracilis Z group showed no edema, inflammation, and fibrosis of the synovial membrane, or pannus formation and destruction of articular cartilage in the femoral trochlear groove. Furthermore, E. gracilis Z and paramylon exhibited symptom-relieving effects on rheumatoid arthritis and suppressed the secretion of cytokines IL-17, IL-6, and IFN-γ. These effects were likely mediated by the regulatory activities of E. gracilis Z and paramylon on Th17 immunity. In addition, the symptom-relieving effects of both substances were comparable, which suggests that paramylon is the active component of Euglena gracilis Z.

  7. Genotoxicity and subchronic toxicity evaluation of dried Euglena gracilis ATCC PTA-123017.

    Science.gov (United States)

    Simon, Ryan R; Vo, Trung D; Levine, Robert

    2016-10-01

    Euglena gracilis is a microalga capable of synthesizing various nutrients of interest in human and animal nutrition. When cultivated aerobically in the dark, Euglena synthesize paramylon, a storage polysaccharide comprised of high molecular weight beta-1,3-D-glucose polymers organized in cytoplasmic granules. Beta-glucans have been shown to have immune modulation effects, including anti-microbial, anti-tumor, and anti-oxidant properties, and metabolic effects, such as regulation of cholesterol and blood sugar levels. Preparations of E. gracilis and paramylon may therefore have potential utility as functional food ingredients for human and animal nutrition. A battery of toxicological studies was conducted on a dried preparation of E. gracilis and paramylon to support their safe food use. The dried alga was not genotoxic in a bacterial reverse mutation test and mammalian micronucleus test. In the subchronic toxicity study, rats were provided E. gracilis in the diet at levels of 0, 12,500, 25,000 or 50,000 ppm. Paramylon was provided at a concentration of 50,000 ppm. No effects that could be attributable to treatment were observed in clinical observations, body weight, food consumption, ophthalmology, hematology and clinical chemistry, urinalysis, and macroscopic and microscopic findings. A NOAEL of 50,000 ppm in the diet was determined for both ingredients. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Effect of γ-irradiation on Euglena gracilis Algae

    International Nuclear Information System (INIS)

    Hlinkova, E.; Zhuchkina, N.I.; Koltovaya, N.A.; Koltovoj, N.A.

    2011-01-01

    Given the prospects for using Euglena algae as part of the biological systems of human life support in long-term space flights, we studied the effects of low doses of radiation and genotype influence on the radiosensitivity of Euglena cells. Irradiation of several Euglena gracilis strains with 60 Co γ-rays shows that strain Z is the most radioresistant. Its chloroplastless derivate OFL strain shows increased radiosensitivity. The E. bacillaris strain and its derivates W3 and W10 without chlorophyll have intermediate radiosensitivity. Irradiation up to 10 Gy had the hormesis effect on the initial strains, and it is only above 100 Gy that cell death was observed. The hormesis effect was observed concerning both radioresistance and growth rate. The use of methylen blue and fluorochrome dyes allows a rapid estimation of the share of the living and dead cells. A comparison of two survival rate tests shows that the classical method of plating on a growth medium yields an increased death rate because this method does not take into account the living non-dividing cells

  9. Gravitaxis of Euglena gracilis depends only partially on passive buoyancy

    Science.gov (United States)

    Richter, Peter R.; Schuster, Martin; Lebert, Michael; Streb, Christine; Häder, Donat-Peter

    In darkness, the unicellular freshwater flagellate Euglena gracilis shows a pronounced negative gravitactic behavior, and the cells swim actively upward in the water column. Up to now it was unclear whether this behavior is based on a passive (physical) alignment mechanism (e.g., buoyancy due to a fore-aft asymmetry of the cell body) or on an active physiological mechanism. A sounding rocket experiment was performed in which the effect of sub-1g-accelerations (0.05, 0.08, 0.12, and 0.2g) on untreated living cells and immobilized (fixation with liquid nitrogen) cells was observed. By means of computerized image analysis the angles of the cells long axis with respect to the acceleration vector were analyzed in order to calculate and compare the reorientation kinetics of the immobilized cells versus that of the controls. In both groups, the reorientation kinetics depended on the dose, but the reorientation of the living cells was about five times faster than that of the immobilized cells. This indicates that in young cells gravitaxis can be explained by a physical mechanism only to a small extend. In older cultures, in which the cells often have a drop shaped cell body, the physical reorientation is considerably faster, and a more pronounced influence of passive alignment caused by fore/aft asymmetry (drag-gravity model) can not be excluded. In addition to these results, Euglena gracilis cells seem to respond very sensitively to small accelerations when they are applied after a longer microgravity period. The data indicate that gravitactic orientation occurred at an acceleration as low as 0.05g.

  10. High-Throughput Accurate Single-Cell Screening of Euglena gracilis with Fluorescence-Assisted Optofluidic Time-Stretch Microscopy.

    Directory of Open Access Journals (Sweden)

    Baoshan Guo

    Full Text Available The development of reliable, sustainable, and economical sources of alternative fuels is an important, but challenging goal for the world. As an alternative to liquid fossil fuels, algal biofuel is expected to play a key role in alleviating global warming since algae absorb atmospheric CO2 via photosynthesis. Among various algae for fuel production, Euglena gracilis is an attractive microalgal species as it is known to produce wax ester (good for biodiesel and aviation fuel within lipid droplets. To date, while there exist many techniques for inducing microalgal cells to produce and accumulate lipid with high efficiency, few analytical methods are available for characterizing a population of such lipid-accumulated microalgae including E. gracilis with high throughout, high accuracy, and single-cell resolution simultaneously. Here we demonstrate high-throughput, high-accuracy, single-cell screening of E. gracilis with fluorescence-assisted optofluidic time-stretch microscopy-a method that combines the strengths of microfluidic cell focusing, optical time-stretch microscopy, and fluorescence detection used in conventional flow cytometry. Specifically, our fluorescence-assisted optofluidic time-stretch microscope consists of an optical time-stretch microscope and a fluorescence analyzer on top of a hydrodynamically focusing microfluidic device and can detect fluorescence from every E. gracilis cell in a population and simultaneously obtain its image with a high throughput of 10,000 cells/s. With the multi-dimensional information acquired by the system, we classify nitrogen-sufficient (ordinary and nitrogen-deficient (lipid-accumulated E. gracilis cells with a low false positive rate of 1.0%. This method holds promise for evaluating cultivation techniques and selective breeding for microalgae-based biofuel production.

  11. Trophic transfer of gold nanoparticles from Euglena gracilis or Chlamydomonas reinhardtii to Daphnia magna

    International Nuclear Information System (INIS)

    Lee, Woo-Mi; Yoon, Sung-Ji; Shin, Yu-Jin; An, Youn-Joo

    2015-01-01

    Understanding the trophic transfer of nanoparticles (NPs) is important because NPs are small enough to easily penetrate into organisms. In this study, we evaluated the trophic transfer of gold NPs (AuNPs) within the aquatic food chain. We observed AuNPs transfer from 2 species of primary producers (Chlamydomonas reinhardtii or Euglena gracilis) to the primary consumer (Daphnia magna). Also, bioaccumulation of AuNPs in E. gracilis was higher than that in C. reinhardtii. The reasons for the difference in Au accumulation may be the physical structure of these organisms, and the surface area that is available for interaction with NPs. C. reinhardtii has a cell wall that may act as a barrier to the penetration of NPs. The size of E. gracilis is larger than that of C. reinhardtii. This study demonstrates the trophic transfer of AuNPs from a general producer to a consumer in an aquatic environment. - Highlights: • This study evaluated the trophic transfer of AuNPs in an aquatic food chain. • Chlamydomonas reinhardtii and Euglena gracilis were selected as the primary producers. • Daphnia magna was used as the primary consumer. • The bioaccumulation of AuNPs in E. gracilis was higher than that in C. reinhardtii. • AuNPs were transferred from C. reinhardtii and E. gracilis to D. magna. - Gold nanoparticles can transfer from primary producers (Chlamydomonas reinhardtii or Euglena gracilis) to the primary consumer (Daphnia magna) in an aquatic environment

  12. Sequence Evidence for the Presence of Two Tetrapyrrole Pathways in Euglena gracilis

    Czech Academy of Sciences Publication Activity Database

    Kořený, Luděk; Oborník, Miroslav

    2011-01-01

    Roč. 3, - (2011), 359-364 ISSN 1759-6653 R&D Projects: GA ČR GA206/08/1423; GA ČR GD206/09/H026 Institutional research plan: CEZ:AV0Z60220518 Keywords : tetrapyrrole synthesis * heme pathway * Euglena gracilis * secondary endosymbiosis * evolution * plastid Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 4.618, year: 2011

  13. Effects of Euglena (Euglena gracilis) supplemented to diet (forage: concentrate ratios of 60:40) on the basic ruminal fermentation and methane emissions in in vitro condition

    OpenAIRE

    Aemiro, Ashagrie; Watanabe, Shota; Suzuki, Kengo; Hanada, Masaaki; Umetsu, Kazutaka

    2016-01-01

    An in vitro study was conducted to investigate the effect of different concentrations of Euglena (Euglena gracilis) on CH4 production, dry matter (DM) digestibility, volatile fatty acid (VFA) and ammonia N(NH3-N) concentration as well as on the protozoa population. The treatments considered were Euglena at concentrations of 0.0, 50, 100, 200, 400 and 1000 g/kg dry matter (DM) of the substrate (60:40 forage: concentrate ratio) incubated for 24 and 96 h using an in vitro continuous gas producti...

  14. Physiological characterization of gravitaxis in Euglena gracilis and Astasia longa studied on sounding rocket flights.

    Science.gov (United States)

    Richter, P R; Lebert, M; Tahedl, H; Hader, D P

    2001-01-01

    Euglena gracilis is a photosynthetic, unicellular flagellate found in eutrophic freshwater habitats. The organisms control their vertical position in the water column using gravi- and phototaxis. Recent experiments demonstrated that negative gravitaxis cannot be explained by passive buoyancy but by an active physiological mechanism. During space experiments, the threshold of gravitaxis was determined to be between 0.08 and 0.12 x g. A strong correlation between the applied acceleration and the intracellular cAMP and Ca2+ was observed. The results support the hypothesis, that the cell body of Euglena, which is denser than the surrounding medium exerts a pressure onto the lower membrane and activates mechanosensitive Ca2+ channels. Changes in the membrane potential and the cAMP concentration are most likely subsequent elements in a signal transduction chain, which results in reorientation strokes of the flagellum. c 2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved.

  15. Cadmium removal by Euglena gracilis is enhanced under anaerobic growth conditions

    Energy Technology Data Exchange (ETDEWEB)

    Santiago-Martínez, M. Geovanni; Lira-Silva, Elizabeth; Encalada, Rusely; Pineda, Erika; Gallardo-Pérez, Juan Carlos [Departamento de Bioquímica, Instituto Nacional de Cardiología (Mexico); Zepeda-Rodriguez, Armando [Facultad de Medicina, UNAM, Mexico City (Mexico); Moreno-Sánchez, Rafael; Saavedra, Emma [Departamento de Bioquímica, Instituto Nacional de Cardiología (Mexico); Jasso-Chávez, Ricardo, E-mail: rjass_cardiol@yahoo.com.mx [Departamento de Bioquímica, Instituto Nacional de Cardiología (Mexico)

    2015-05-15

    Highlights: • The protist Euglena gracilis had the ability to grow and remove large amounts of Cd{sup 2+} under anaerobic conditions. • High biomass was attained by combination of glycolytic and mitochondrial carbon sources. • Routes of degradation of glucose, glutamate and malate under anaerobic conditions in E. gracilis are described. • Biosorption was the main mechanism of Cd{sup 2+} removal in anaerobiosis, whereas the Cd{sup 2+} intracellularly accumulated was inactivated by thiol-molecules and polyphosphate. - Abstract: The facultative protist Euglena gracilis, a heavy metal hyper-accumulator, was grown under photo-heterotrophic and extreme conditions (acidic pH, anaerobiosis and with Cd{sup 2+}) and biochemically characterized. High biomass (8.5 × 10{sup 6} cells mL{sup −1}) was reached after 10 days of culture. Under anaerobiosis, photosynthetic activity built up a microaerophilic environment of 0.7% O{sub 2}, which was sufficient to allow mitochondrial respiratory activity: glutamate and malate were fully consumed, whereas 25–33% of the added glucose was consumed. In anaerobic cells, photosynthesis but not respiration was activated by Cd{sup 2+} which induced higher oxidative stress. Malondialdehyde (MDA) levels were 20 times lower in control cells under anaerobiosis than in aerobiosis, although Cd{sup 2+} induced a higher MDA production. Cd{sup 2+} stress induced increased contents of chelating thiols (cysteine, glutathione and phytochelatins) and polyphosphate. Biosorption (90%) and intracellular accumulation (30%) were the mechanisms by which anaerobic cells removed Cd{sup 2+} from medium, which was 36% higher versus aerobic cells. The present study indicated that E. gracilis has the ability to remove Cd{sup 2+} under anaerobic conditions, which might be advantageous for metal removal in sediments from polluted water bodies or bioreactors, where the O{sub 2} concentration is particularly low.

  16. Cadmium removal by Euglena gracilis is enhanced under anaerobic growth conditions

    International Nuclear Information System (INIS)

    Santiago-Martínez, M. Geovanni; Lira-Silva, Elizabeth; Encalada, Rusely; Pineda, Erika; Gallardo-Pérez, Juan Carlos; Zepeda-Rodriguez, Armando; Moreno-Sánchez, Rafael; Saavedra, Emma; Jasso-Chávez, Ricardo

    2015-01-01

    Highlights: • The protist Euglena gracilis had the ability to grow and remove large amounts of Cd 2+ under anaerobic conditions. • High biomass was attained by combination of glycolytic and mitochondrial carbon sources. • Routes of degradation of glucose, glutamate and malate under anaerobic conditions in E. gracilis are described. • Biosorption was the main mechanism of Cd 2+ removal in anaerobiosis, whereas the Cd 2+ intracellularly accumulated was inactivated by thiol-molecules and polyphosphate. - Abstract: The facultative protist Euglena gracilis, a heavy metal hyper-accumulator, was grown under photo-heterotrophic and extreme conditions (acidic pH, anaerobiosis and with Cd 2+ ) and biochemically characterized. High biomass (8.5 × 10 6 cells mL −1 ) was reached after 10 days of culture. Under anaerobiosis, photosynthetic activity built up a microaerophilic environment of 0.7% O 2 , which was sufficient to allow mitochondrial respiratory activity: glutamate and malate were fully consumed, whereas 25–33% of the added glucose was consumed. In anaerobic cells, photosynthesis but not respiration was activated by Cd 2+ which induced higher oxidative stress. Malondialdehyde (MDA) levels were 20 times lower in control cells under anaerobiosis than in aerobiosis, although Cd 2+ induced a higher MDA production. Cd 2+ stress induced increased contents of chelating thiols (cysteine, glutathione and phytochelatins) and polyphosphate. Biosorption (90%) and intracellular accumulation (30%) were the mechanisms by which anaerobic cells removed Cd 2+ from medium, which was 36% higher versus aerobic cells. The present study indicated that E. gracilis has the ability to remove Cd 2+ under anaerobic conditions, which might be advantageous for metal removal in sediments from polluted water bodies or bioreactors, where the O 2 concentration is particularly low

  17. Effect of chromium on the fatty acid composition of two strains of Euglena gracilis

    Energy Technology Data Exchange (ETDEWEB)

    Rocchetta, Iara [Departamento de Biodiversidad y Biologia Experimental, Universidad de Buenos Aires, Pab. II, Ciudad Universitaria, 1428 Buenos Aires (Argentina)]. E-mail: rocchetta@bg.fcen.uba.ar; Mazzuca, Marcia [Departamento de Quimica, Facultad de Ciencias Naturales, Universidad de Patagonia, Comodoro Rivadavia, Chubut (Argentina); Conforti, Visitacion [Departamento de Biodiversidad y Biologia Experimental, Universidad de Buenos Aires, Pab. II, Ciudad Universitaria, 1428 Buenos Aires (Argentina); Ruiz, Laura [Departamento de Biodiversidad y Biologia Experimental, Universidad de Buenos Aires, Pab. II, Ciudad Universitaria, 1428 Buenos Aires (Argentina); Balzaretti, Vilma [Departamento de Quimica, Facultad de Ciencias Naturales, Universidad de Patagonia, Comodoro Rivadavia, Chubut (Argentina); Rios de Molina, Maria del Carmen [Departamento de Quimica Biologica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Pab. II, Ciudad Universitaria, 1428 Buenos Aires (Argentina)

    2006-05-15

    The effect of hexavalent chromium on fatty acid composition was studied in two strains of Euglena gracilis; UTEX 753 (from the Culture Collection of Algae of Texas University, USA) and MAT (isolated from a highly polluted River). Both were grown in photoauxotrophic and photoheterotrophic conditions and exposed to two metal concentrations, one below and one above IC{sub 5}. The high malondialdehyde (MDA) levels (3 to 7-fold) obtained with chromium concentration above IC{sub 5}, suggested the existence of metal-induced lipid peroxidation. Total lipid content increased only with concentration below IC{sub 5}, whereas it was inhibited by higher metal concentration. Photoheterotrophic control strains exhibited a significantly higher proportion of saturated and polyunsaturated fatty acids. Polyunsaturated acids were most affected by chromium, especially those related to chloroplast structures. Ultra-structure studies showed clear thylakoid disorganization in all treated cells. The results indicate that hexavalent chromium affects levels of fatty acids, especially those related to photosynthetic activity. - Fatty acid evaluation in the presence of chromium in Euglena gracilis grown in different culture conditions.

  18. Effect of chromium on the fatty acid composition of two strains of Euglena gracilis

    International Nuclear Information System (INIS)

    Rocchetta, Iara; Mazzuca, Marcia; Conforti, Visitacion; Ruiz, Laura; Balzaretti, Vilma; Rios de Molina, Maria del Carmen

    2006-01-01

    The effect of hexavalent chromium on fatty acid composition was studied in two strains of Euglena gracilis; UTEX 753 (from the Culture Collection of Algae of Texas University, USA) and MAT (isolated from a highly polluted River). Both were grown in photoauxotrophic and photoheterotrophic conditions and exposed to two metal concentrations, one below and one above IC 5 . The high malondialdehyde (MDA) levels (3 to 7-fold) obtained with chromium concentration above IC 5 , suggested the existence of metal-induced lipid peroxidation. Total lipid content increased only with concentration below IC 5 , whereas it was inhibited by higher metal concentration. Photoheterotrophic control strains exhibited a significantly higher proportion of saturated and polyunsaturated fatty acids. Polyunsaturated acids were most affected by chromium, especially those related to chloroplast structures. Ultra-structure studies showed clear thylakoid disorganization in all treated cells. The results indicate that hexavalent chromium affects levels of fatty acids, especially those related to photosynthetic activity. - Fatty acid evaluation in the presence of chromium in Euglena gracilis grown in different culture conditions

  19. Kinematics of flagellar swimming in Euglena gracilis: Helical trajectories and flagellar shapes.

    Science.gov (United States)

    Rossi, Massimiliano; Cicconofri, Giancarlo; Beran, Alfred; Noselli, Giovanni; DeSimone, Antonio

    2017-12-12

    The flagellar swimming of euglenids, which are propelled by a single anterior flagellum, is characterized by a generalized helical motion. The 3D nature of this swimming motion, which lacks some of the symmetries enjoyed by more common model systems, and the complex flagellar beating shapes that power it make its quantitative description challenging. In this work, we provide a quantitative, 3D, highly resolved reconstruction of the swimming trajectories and flagellar shapes of specimens of Euglena gracilis We achieved this task by using high-speed 2D image recordings taken with a conventional inverted microscope combined with a precise characterization of the helical motion of the cell body to lift the 2D data to 3D trajectories. The propulsion mechanism is discussed. Our results constitute a basis for future biophysical research on a relatively unexplored type of eukaryotic flagellar movement. Copyright © 2017 the Author(s). Published by PNAS.

  20. A new homolog of FocA transporters identified in cadmium-resistant Euglena gracilis

    International Nuclear Information System (INIS)

    Delomenie, Claudine; Foti, Emilie; Floch, Enora; Diderot, Vimala; Porquet, Dominique; Dupuy, Corinne; Bonaly, Jacqueline

    2007-01-01

    To better understand the cellular mechanism of stress resistance to various pollutants (cadmium, pentachlorophenol), we undertook a survey of the Euglena gracilis transcriptome by mRNA differential display and cDNA cloning. We performed a real-time RT-PCR analysis upon four selected genes. One of them significantly changed its expression level in response to stress treatments: B25 gene was overexpressed in Cd-resistant cells whereas it was down-regulated in PCP-adapted cells. By Race assays we obtained for B25 a 1093 bp cDNA. The deduced protein was identified as a bacterial formate/nitrite transporter (FocA) homolog and the gene was named EgFth. From all the data, we concluded that EgFth overexpression was related to chronic exposure to cadmium

  1. Protein synthesis during the initial phase of the temperature-induced bleaching response in Euglena gracilis

    International Nuclear Information System (INIS)

    Ortiz, W.

    1990-01-01

    Growing cultures of photoheterotrophic Euglena gracilis experience an increase in chlorophyll accumulation during the initial phase of the temperature-induced bleaching response suggesting an increase in the synthesis of plastid components at the bleaching temperature of 33 degree C. A primary goal of this work was to establish whether an increase in the synthesis of plastid proteins accompanies the observed increase in chlorophyll accumulation. In vivo pulse-labeling experiments with [ 35 S]sodium sulfate were carried out with cells grown at room temperature or at 33 degree C. The synthesis of a number of plastid polypeptides of nucleocytoplasmic origin, including some presumably novel polypeptides, increased in cultures treated for 15 hours at 33 degree C. In contrast, while synthesis of thylakoid proteins by the plastid protein synthesis machinery decreased modestly, synthesis of the large subunit of the enzyme ribulosebisphosphate carboxylase was strongly affected at the elevated temperature. Synthesis of novel plastid-encoded polypeptides was not induced at the bleaching temperature. It is concluded that protein synthesis in plastids declines during the initial phase of the temperature response in Euglena despite an overall increase in cellular protein synthesis and an increase in chlorophyll accumulation per cell

  2. Low-resolution characterization of the 3D structure of the Euglena gracilis photoreceptor

    International Nuclear Information System (INIS)

    Barsanti, Laura; Coltelli, Primo; Evangelista, Valtere; Passarelli, Vincenzo; Frassanito, Anna Maria; Vesentini, Nicoletta; Gualtieri, Paolo

    2008-01-01

    This paper deals with the first characterization of the structure of the photoreceptive organelle of the unicellular alga Euglena gracilis (Euglenophyta). This organelle has a three-dimensional organization consisting of up to 50 closely stacked membrane lamellae. Ionically induced unstacking of the photoreceptor lamellae revealed ordered arrays well suited to structural analysis by electron microscopy and image analysis, which ultimately yielded a low-resolution picture of the structure. Each lamella is formed by the photoreceptive membrane protein of the cell assembled within the membrane layer in a hexagonal lattice. The first order diffraction spots in the calculated Fourier transform reveals the presence of 6-fold symmetrized topography (better resolution about 90 A). The 2D and 3D structural data are very similar with those recently published on proteorodopsin, a membrane protein used by marine bacterio-plankton as light-driven proton pump. In our opinion these similarity indicate that a photoreceptive protein belonging to the same superfamily of proteorodopsin could form the Euglena photoreceptor

  3. Amino acids as possible alternative nitrogen source for growth of Euglena gracilis Z in life support systems.

    Science.gov (United States)

    Richter, P R; Liu, Y; An, Y; Li, X; Nasir, A; Strauch, S M; Becker, I; Krüger, J; Schuster, M; Ntefidou, M; Daiker, V; Haag, F W M; Aiach, A; Lebert, M

    2015-01-01

    In recent times Euglena gracilis Z was employed as primary producer in closed environmental life-support system (CELSS), e.g. in space research. The photosynthetic unicellular flagellate is not capable of utilizing nitrate, nitrite, and urea as nitrogen source. Therefore, ammonium is supplied as an N-source in the lab (provided as diammonium-dihydrogenphosphate, (NH4)2HPO4) to E. gracilis cultures. While nitrate exerts low toxicity to organisms, ammonium is harmful for many aquatic organisms especially, at high pH-values, which causes the ionic NH4+ (low toxicity) to be partially transformed into the highly toxic ammonia, NH3. In earlier reports, Euglena gracilis was described to grow with various amino acids as sole N-source. Our aim was to investigate alternatives for (NH4)2HPO4 as N-source with lower toxicity for organisms co-cultivated with Euglena in a CELSS. The growth kinetics of Euglena gracilis cultures was determined in the presence of different amino acids (glycine, glutamine, glutamic acid, leucine, and threonine). In addition, uptake of those amino acids by the cells was measured. Cell growth in the presence of glycine and glutamine was quite comparable to the growth in (NH4)2HPO4 containing cultures while a delay in growth was observed in the presence of leucine and threonine. Unlike, aforementioned amino acids glutamate consumption was very poor. Cell density and glutamate concentration were almost unaltered throughout the experiment and the culture reached the stationary phase within 8 days. The data are compared with earlier studies in which utilization of amino acids in Euglena gracilis was investigated. All tested amino acids (glutamate with limitations) were found to have the potential of being an alternative N-source for Euglena gracilis. Hence, these amino acids can be used as a non-toxic surrogate for (NH4)2HPO4. Copyright © 2014 The Committee on Space Research (COSPAR). Published by Elsevier Ltd. All rights reserved.

  4. The effect of 60Co γ-rays on the contents of paramylon and trehalose in Euglena gracilis

    International Nuclear Information System (INIS)

    Furuta, M.; Maruyama, A.; Nakazawa, M.; Ueda, M.; Miyatake, K.; Kato, A.; Enomoto, T.

    2003-01-01

    Full text: It is reported that the non-reducing disaccharide trehalose is accumulated in various organisms and protects biomolecules against various environmental stresses including heat shock, osmotic shock, and oxidative stresses. Euglena (Euglena gracilis) is photosynthetic unicellular organisms which is classified both as animal and as plant because of its motility. In our previous study, it was shown that salt stress causes degradation of paramylon, the reserve carbohydrate of Euglena, and trehalose, the degraded product of paramylon, accumulated simultaneously to maintain the osmotic pressure of Euglena cells. Euglena is known to be radiation-resistant more than Escherichia coli and other bacteria. Therefore, we have investigated whether or not the same phenomenon could be observed in Euglena after 60 Co-gamma irradiation. Exposure of the native Z strain and chloroplast-deficient SM-ZK strain of Euglena to a dose of 500 kGy induced significant paramylon degradation and trehalose accumulation during the incubation in the Koren-Hunter culture medium containing glucose as carbon source after the irradiation. Forty percent of the paramylon was degraded within 10-hr incubation after the irradiation but accumulated trehalose content was about one sixth of that by salt stress. Trehlose accumulation disappeared when the irradiated cells were incubated in phosphate buffer but it recovered when glucose is added to the buffer to the same concentration as K-H media. These results suggest that trehalose accumulation in irradiated Euglena cells plays a role in protecting cellular constituents from oxidative damage caused by gamma-irradiation independently of the response to salt stress

  5. Gravitaxis in the flagellate Euglena gracilis--results from NiZeMi, clinostat and sounding rocket flights.

    Science.gov (United States)

    Häder, D P

    1994-05-01

    Many motile microorganisms including flagellates such as the green Euglena gracilis move up and down within the water column and use a number of external clues for their orientation, the most important of which may be light and gravity. The cells use positive phototaxis and negative gravitaxis to move closer to the surface of the water column which for energetic reasons is vital for their survival. However, most phytoplankton organisms cannot tolerate the bright irradiance of unfiltered solar radiation at the surface which also bleaches the photosynthetic pigments, disables the photosynthetic apparatus and impairs phototaxis, gravitaxis and motility in Euglena. Thus, it is not surprising that at higher irradiances negative phototaxis operates antagonistically to the responses described above to guide the cells into deeper water where they are protected from excessive radiation. Phototaxis and gravitaxis are not independent from one another: in a vertically positioned cuvette negative gravitaxis can be "titrated" by light impinging from above and is compensated at about 30 W m-2. While the photoreceptor for phototaxis has been identified in Euglena gracilis biochemically and spectroscopically, the gravireceptor is not yet known. Young cultures of Euglena gracilis show a positive gravitaxis, the ecological signficance of which is not yet understood while older cultures show negative gravitaxis. One hypothesis concerning the nature of graviperception is based on a passive physical process such as an asymmetric distribution of the mass within the cell. However, the observation that short term UV irradiation decreases the precision of negative gravitaxis rather indicates the involvement of an active physiological gravireceptor. Furthermore, some heavy metal ions have been found to change the direction of movement from positive to negative gravitaxis in young cells.

  6. Gravitactic orientation of Euglena gracilis – a sensitive endpoint for ecotoxicological assessment of water pollutants

    Directory of Open Access Journals (Sweden)

    Aziz eUllah

    2013-12-01

    Full Text Available Pollution of aquatic environments with natural and anthropogenically produced substances is one of the major environmental problems of the world. In many countries the decreasing quantity of water coupled with its increasing usage in multiple sectors has adversely affected water quality and caused problems of water pollution. Polluted water has been a main cause of adverse effects on plants, animals and humans throughout the world. Physicochemical analysis of water, which is a common method used for quality assessment of water, alone may not be enough as it cannot evaluate the impact on living organisms. Therefore, bioassessment of water and wastewater quality is considered to be essential to reflect the ultimate effects on living organisms. Many organisms like bacteria, algae, fish, invertebrates and protozoan are used as bioassay organisms for assessment of water quality. This review article elucidates the use of Euglena gracilis, a freshwater motile flagellate of the phylum Euglenophyta, as a suitable organism in ecotoxicological studies with special emphasis on its gravitactic orientation as a sensitive end point in ecotoxicological assessment of water pollutants.

  7. Compression and release dynamics of an active matter system of Euglena gracilis

    Science.gov (United States)

    Lam, Amy; Tsang, Alan C. H.; Ouellette, Nicholas; Riedel-Kruse, Ingmar

    Active matter, defined as ensembles of self-propelled particles, encompasses a large variety of systems at all scales, from nanoparticles to bird flocks. Though various models and simulations have been created to describe the dynamics of these systems, experimental verification has been difficult to obtain. This is frequently due to the complex interaction rules which govern the particle behavior, in turn making systematic varying of parameters impossible. Here, we propose a model for predicting the system evolution of compression and release of an active system based on experiments and simulations. In particular, we consider ensembles of the unicellular, photo-responsive algae, Euglena gracilis, under light stimulation. By varying the spatiotemporal light patterns, we are able to finely adjust cell densities and achieve arbitrary non-homogeneous distributions, including compression into high-density aggregates of varying geometries. We observe the formation of depletion zones after the release of the confining stimulus and investigate the effects of the density distribution and particle rotational noise on the depletion. These results provide implications for defining state parameters which determine system evolution.

  8. Effects of solar and artificial UV irradiation on motility and phototaxis in the flagellate, Euglena gracilis

    International Nuclear Information System (INIS)

    Haeder, D.-P.

    1986-01-01

    The effect of solar irradiation on the percentage of motile cells, their average speed and their phototactic orientation to white actinic light was studied in the flagellate, Euglena gracilis. Unfiltered solar radiation in midsummer during mid-day at a location near Lisboa, Portugal, was found to impair motility within 2 h. This effect is exclusively due to the UV-B component of the radiation and not due to UV-A, visible light or a temperature increase. Likewise, phototactic orientation was drastically impaired. Reduction of the solar UV-B irradiation by insertion of an ozone-flooded plexiglass cuvette partially reduced the inhibition and covering the cuvettes with glass prevented any decrease in motility and photoorientation. Similar results were found with artificial irradiation (Xe lamps). After inoculation, the motility of the population follows an optimum curve (optimum at 8 days). Also, the UV-B effect on motility was smallest after about one week and increased for younger and older cultures. (author)

  9. Applicability of Euglena gracilis for biorefineries demonstrated by the production of α-tocopherol and paramylon followed by anaerobic digestion.

    Science.gov (United States)

    Grimm, Philipp; Risse, Joe M; Cholewa, Dominik; Müller, Jakob M; Beshay, Usama; Friehs, Karl; Flaschel, Erwin

    2015-12-10

    In this study the use of Euglena gracilis biomass for α-tocopherol, paramylon and biogas production in a value-added chain was investigated. Therefore, we analyzed the dry cell weight and product concentrations at different growth phases during heterotrophic, photoheterotrophic and photoautotrophic cultivation in a low-cost minimal medium. Furthermore, the specific biogas yields for differently derived biomass with and without product recovery were investigated. We demonstrate that growth phase and cultivation mode not only have a significant impact on product formation, but also influence the yield of biogas obtained from anaerobic digestion of Euglena gracilis biomass. The maximum dry cell weight concentration ranged from 12.3±0.14gL(-1) for heterotrophically to 3.4±0.02gL(-1) for photoautotrophically grown Euglena gracilis cells. The heterotrophically grown biomass accumulated product concentrations of 5.3±0.12mgL(-1) of α-tocopherol and 9.3±0.1gL(-1) of paramylon or 805±10.9mL of biogasgvs(-1) (per gram volatile solids). The results for photoautotrophically grown cells were 8.6±0.22mgL(-1) of α-tocopherol and 0.78±0.01gL(-1) of paramylon or 648±7.2mL of biogasgvs(-1). For an energy-saving downstream procedure the extracting agent methanol does not have to be removed strictly. Samples with residual methanol showed a significantly increased biogas yield, because the solvent can be used as an additional substrate for methane production by archaebacteria. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Restart capability of resting-states of Euglena gracilis after 9 months of dormancy: preparation for autonomous space flight experiments

    Science.gov (United States)

    Strauch, Sebastian M.; Becker, Ina; Pölloth, Laura; Richter, Peter R.; Haag, Ferdinand W. M.; Hauslage, Jens; Lebert, Michael

    2018-04-01

    Dormant states of organisms are easier to store than the living state because they tolerate larger variations in temperature, light, storage space etc., making them attractive for laboratory culture stocks and also for experiments under special circumstances, especially space flight experiments. Like several other organisms, Euglena gracilis is capable of forming desiccation tolerant resting states in order to survive periods of unfavourable environmental conditions. In earlier experiments it was found that dormant Euglena cells must not become completely desiccated. Some residual moisture is required to ensure recovery of the resting states. To analyse the water demand in recovery of Euglena resting states, cells were transferred to a defined amount of cotton wool (0.5 g). Subsequently different volumes of medium (1, 2, 3, 4, 5, 8, 10 and 20 ml) were added in order to supply humidity; a control was set up without additional liquid. Samples were sealed in transparent 50 ml falcon tubes and stored for 9 months under three different conditions: • Constant low light conditions in a culture chamber at 20°C, • In a black box, illuminated with short light emitting diode-light pulses provided by joule thieves and • In darkness in a black box. After 9 months, cells were transferred to fresh medium and cell number, photosynthetic efficiency and movement behavior was monitored over 3 weeks. It was found that cells recovered under all conditions except in the control, where no medium was supplied. Transcription levels of 21 genes were analysed with a Multiplex-polymerase chain reaction. One hour after rehydration five of these genes were found to be up-regulated: ubiquitin, heat shock proteins HSP70, HSP90, the calcium-sensor protein frequenin and a distinct protein kinase, which is involved in gravitaxis. The results indicate a transient general stress response of the cells.

  11. The different phenotypes of phot- photosynthetic deficient mutants in Euglena gracilis: the frequency of production by ultraviolet irradiation

    International Nuclear Information System (INIS)

    Nicolas, Paul; Heizmann, Philippe; Nigon, Victor

    1982-01-01

    In Euglena gracilis, pigment-less mutants appear spontaneously with a frequency of about 2-5x10 -3 . Ultraviolet-irradiation increases the proportion of chlorophyll-less colonies to an upper limit where green colonies represent 4x10 -4 of the surviving ones. This limit might indicate the occurrence of processes involving repair of the chloroplastic DNA. Most of the photosynthetic-deficient (phot - ) mutants induced by ultraviolet irradiation are characterized by the presence of a reduced number of chloroplast DNA molecules showing deletions (phi - class). Most of the phi - mutants present the phenotype phi - chlo - car - , where neither chlorophyll nor carotenoids are obvious: the phi - chlo - car + mutants, devoid of chlorophyll but containing carotenoids, are obtained among the phi - strains with a frequency lower than 10 -3 . The phot - mutants which belong to the cp - class are characterized by the maintenance of a great number of chloroplastic DNA molecules, where large deletions are absent: their occurrence after ultraviolet irradiation is low [fr

  12. Evaluación de la bioacumulación de cobre en Euglena gracilis mediante la técnica de fluorescencia de rayos X

    Directory of Open Access Journals (Sweden)

    David Cervantes-Garcia

    2014-07-01

    Full Text Available En esta investigación se evaluó el efecto de la exposición de cobre en la capacidad de bioacumulación de metal en células de Euglena gracilis. La acumulación de metal medida con la técnica de fluorescencia de rayos X (XRF mostró que la acumulación de Cu+2 en E. gracilis fue dosis dependiente y se incrementó significativamente en las células tratadas con 0.4 y 0.8 mM de Cu+2 con respecto al control. No se descarta la presencia de una estrategia de acumulación en E. gracilis que podría involucrar la participación de una serie de múltiples procesos, como producción de vacuolas. Futuros estudios al respecto deberán orientarse a evaluar la capacidad de bioacumulación de E. gracilis para su aplicación en programas de biorremediación de sistemas acuáticos.

  13. Modulating effects of orally supplied Euglena gracilis on the physiological responses of the freshwater mussel Diplodon chilensis, exposed to sewage water pollution in a Patagonian river (Argentina).

    Science.gov (United States)

    Bianchi, Virginia A; Castro, Juan M; Rocchetta, Iara; Conforti, Visitación; Pascual, Mariano; Luquet, Carlos M

    2016-04-01

    In order to test if orally supplied Euglena sp. cells modulate the physiological status of bivalves during bioremediation procedures, we evaluated the effect of Euglena gracilis diet on the immune response, oxidative balance and metabolic condition of Diplodon chilensis exposed to sewage water pollution. Mussels were fed for 90 days with E. gracilis (EG) or Scenedesmus vacuolatus (SV, control diet), and then exposed for 10 days at three sites along the Pocahullo river basin: 1) an unpolluted site, upstream of the city (control, C); 2) upstream (UpS) and 3) downstream (DoS) from the main tertiary-treated sewage discharge, in the city of San Martín de los Andes, Northwest Patagonia, Argentina. Our results show that the total hemocyte number decreases while pollution load increases along the river course for both, EG and SV mussels. Phagocytic activity is higher in EG mussels than in SV ones under all conditions. Reactive oxygen species (ROS) production in hemocytes increases with the increase in the pollution load, being significantly higher for EG mussels than for SV ones at DoS; no changes are observed for total oxyradical scavenging capacity (TOSC). Hemocytes' viability is increased for E. gracilis diet at C and remains unchanged in this group of mussels when exposed at the polluted sites. Lysosomal membrane stability is higher in EG mussels than in SV ones for all conditions, although it is decreased at polluted sites compared with that at C. Antioxidant (catalase) and detoxifying (gluthatione S-transferase) defenses are generally lower in gills and digestive gland of EG mussels than in SV ones. Lipid peroxidation (TBARS) is evident in gills of EG mussels at C, and in digestive gland of the same group, at all the sites. Gill mass factor (GF) is affected by the E. gracilis diet; it is increased at C and decreased at polluted sites when compared with that of SV ones. Digestive gland mass factor (DGF) is higher in EG mussels than in SV ones. In D

  14. Euglena gracilis chloroplast DNA: analysis of a 1.6 kb intron of the psb C gene containing an open reading frame of 458 codons.

    Science.gov (United States)

    Montandon, P E; Vasserot, A; Stutz, E

    1986-01-01

    We retrieved a 1.6 kbp intron separating two exons of the psb C gene which codes for the 44 kDa reaction center protein of photosystem II. This intron is 3 to 4 times the size of all previously sequenced Euglena gracilis chloroplast introns. It contains an open reading frame of 458 codons potentially coding for a basic protein of 54 kDa of yet unknown function. The intron boundaries follow consensus sequences established for chloroplast introns related to class II and nuclear pre-mRNA introns. Its 3'-terminal segment has structural features similar to class II mitochondrial introns with an invariant base A as possible branch point for lariat formation.

  15. A 39-kD plasma membrane protein (IP39) is an anchor for the unusual membrane skeleton of Euglena gracilis

    International Nuclear Information System (INIS)

    Rosiere, T.K.; Marrs, J.A.; Bouck, G.B.

    1990-01-01

    The major integral plasma membrane protein (IP39) of Euglena gracilis was radiolabeled, peptide mapped, and dissected with proteases to identify cytoplasmic domains that bind and anchor proteins of the cell surface. When plasma membranes were radioiodinated and extracted with octyl glucoside, 98% of the extracted label was found in IP39 or the 68- and 110-kD oligomers of IP39. The octyl glucoside extracts were incubated with unlabeled cell surface proteins immobilized on nitrocellulose (overlays). Radiolabel from the membrane extract bound one (80 kD) of the two (80 and 86 kD) major membrane skeletal protein bands. Resolubilization of the bound label yielded a radiolabeled polypeptide identical in Mr to IP39. Intact plasma membranes were also digested with papain before or after radioiodination, thereby producing a cytoplasmically truncated IP39. The octyl glucoside extract of truncated IP39 no longer bound to the 80-kD membrane skeletal protein in the nitrocellulose overlays. EM of intact or trypsin digested plasma membranes incubated with membrane skeletal proteins under stringent conditions similar to those used in the nitrocellulose overlays revealed a partially reformed membrane skeletal layer. Little evidence of a membrane skeletal layer was found, however, when plasma membranes were predigested with papain before reassociation. A candidate 80-kD binding domain of IP39 has been tentatively identified as a peptide fragment that was present after trypsin digestion of plasma membranes, but was absent after papain digestion in two-dimensional peptide maps of IP39. Together, these data suggest that the unique peripheral membrane skeleton of Euglena binds to the plasma membrane through noncovalent interactions between the major 80-kD membrane skeletal protein and a small, papain sensitive cytoplasmic domain of IP39

  16. Assessment of the phytochemical constituents and antioxidant activity of a bloom forming microalgae Euglena tuba

    OpenAIRE

    Chaudhuri, Dipankar; Ghate, Nikhil Baban; Deb, Shampa; Panja, Sourav; Sarkar, Rhitajit; Rout, Jayashree; Mandal, Nripendranath

    2014-01-01

    BACKGROUND: Unstable generation of free radicals in the body are responsible for many degenerative diseases. A bloom forming algae Euglena tuba growing abundantly in the aquatic habitats of Cachar district in the state of Assam in North-East India was analysed for its phytochemical contents, antioxidant activity as well as free radical scavenging potentials. RESULTS: Based on the ability of the extract in ABTS•+ radical cation inhibition and Fe3+ reducing power, the obtained results revealed ...

  17. Assessment of the phytochemical constituents and antioxidant activity of a bloom forming microalgae Euglena tuba

    Directory of Open Access Journals (Sweden)

    Dipankar Chaudhuri

    2014-01-01

    Full Text Available BACKGROUND: Unstable generation of free radicals in the body are responsible for many degenerative diseases. A bloom forming algae Euglena tuba growing abundantly in the aquatic habitats of Cachar district in the state of Assam in North-East India was analysed for its phytochemical contents, antioxidant activity as well as free radical scavenging potentials. RESULTS: Based on the ability of the extract in ABTS•+ radical cation inhibition and Fe3+ reducing power, the obtained results revealed the prominent antioxidant activity of the algae, with high correlation coefficient of its TEAC values to the respective phenolic and flavonoid contents. The extract had shown its scavenging activity for different free radicals and 41.89 ± 0.41 µg/ml, 5.83 ± 0.07 µg/ml, 278.46 ± 15.02 µg/ml and 223.25 ± 4.19 µg/ml were determined as the IC50 values for hydroxyl, superoxide, nitric oxide and hypochlorous acid respectively, which are lower than that of the corresponding reference standards. The phytochemical analysis also revealed that the phenolics, flavonoids, alkaloids, tannins and carbohydrates are present in adequate amount in the extract which was confirmed by HPLC analysis. CONCLUSIONS: The results showed that 70% methanol extract of the algae possesses excellent antioxidant and free radical scavenging properties.

  18. Euglena in time: Evolution, control of central metabolic processes and multi-domain proteins in carbohydrate and natural product biochemistry

    Directory of Open Access Journals (Sweden)

    Ellis C. O’Neill

    2015-12-01

    Full Text Available Euglena gracilis is a eukaryotic microalgae that has been the subject of scientific study for hundreds of years. It has a complex evolutionary history, with traces of at least four endosymbiotic genomes and extensive horizontal gene transfer. Given the importance of Euglena in terms of evolutionary cell biology and its unique taxonomic position, we initiated a de novo transcriptome sequencing project in order to understand this intriguing organism. By analysing the proteins encoded in this transcriptome, we can identify an extremely complex metabolic capacity, rivalling that of multicellular organisms. Many genes have been acquired from what are now very distantly related species. Herein we consider the biology of Euglena in different time frames, from evolution through control of cell biology to metabolic processes associated with carbohydrate and natural products biochemistry.

  19. Extra and intracelular activities of carbonic anhydrase of the marine microalga Tetraselmis gracilis (Chlorophyta Atividade extra e intracelular da Anidrase Carbônica na microalga marinha Tetraselmis gracilis (Chlorophyta

    Directory of Open Access Journals (Sweden)

    Marilda Rigobello-Masini

    2003-07-01

    Full Text Available The activities of extra and intracellular carbonic anhydrases (CA were studied in the microalgae Tetraselmis gracilis (Kylin Butcher (Chlorophyta, Prasinophyceae growing in laboratory cultivation. During ten days of batch cultivation, daily determinations of pH, cell number, enzymatic activity, and total dissolved inorganic carbon (DIC, as well as its main species, CO2 and HCO3-, were performed. Enzymatic activity increased as the growing cell population depleted inorganic carbon from the medium. Carbon dioxide concentration decreased quickly, especially in the third day of cultivation, when a significant increase of the intracellular enzymatic activity was observed. Bicarbonate concentration had its largest decrease in the cultivation medium in the fourth day, when the activity of the extracellular enzyme had its largest increase, suggesting its use by the alga through CA activity. After the fourth cultivation day, half of the cultures were aerated with CO2-free atmospheric air, which caused an increase in the total and external activity of the enzyme, although, in this condition, the stationary growth phase began earlier than in cultures aerated with atmospheric air. The pH of the media was measured daily, increasing from the first to the fourth day, and remaining almost constant until the end of the cultivation. Algal material transferred to the dark lost all enzymatic activity.As atividades da Anidrase Carbônica (AC extra e intracelular foram estudadas na microalga marinha Tetraselmis gracilis (Kylin Butcher (Chlorophyta, Prasinophyceae crescendo em cultivos laboratoriais. Durante dez dias de cultivo, determinações diárias do pH, número de células, atividades enzimáticas, carbono inorgânico total dissolvido (CID e suas principais espécies CO2 e HCO3- foram feitas. A atividade enzimática aumentou na medida em que a população celular em crescimento retirava carbono inorgânico do meio de cultivo. A concentração de dióxido de

  20. Anaerobic Coculture of Microalgae with Thermosipho globiformans and Methanocaldococcus jannaschii at 68°C Enhances Generation of n-Alkane-Rich Biofuels after Pyrolysis

    Science.gov (United States)

    Matsuyama, Shigeru; Igarashi, Kensuke; Utsumi, Motoo; Shiraiwa, Yoshihiro; Kuwabara, Tomohiko

    2013-01-01

    We tested different alga-bacterium-archaeon consortia to investigate the production of oil-like mixtures, expecting that n-alkane-rich biofuels might be synthesized after pyrolysis. Thermosipho globiformans and Methanocaldococcus jannaschii were cocultured at 68°C with microalgae for 9 days under two anaerobic conditions, followed by pyrolysis at 300°C for 4 days. Arthrospira platensis (Cyanobacteria), Dunaliella tertiolecta (Chlorophyta), Emiliania huxleyi (Haptophyta), and Euglena gracilis (Euglenophyta) served as microalgal raw materials. D. tertiolecta, E. huxleyi, and E. gracilis cocultured with the bacterium and archaeon inhibited their growth and CH4 production. E. huxleyi had the strongest inhibitory effect. Biofuel generation was enhanced by reducing impurities containing alkanenitriles during pyrolysis. The composition and amounts of n-alkanes produced by pyrolysis were closely related to the lipid contents and composition of the microalgae. Pyrolysis of A. platensis and D. tertiolecta containing mainly phospholipids and glycolipids generated short-carbon-chain n-alkanes (n-tridecane to n-nonadecane) and considerable amounts of isoprenoids. E. gracilis also produced mainly short n-alkanes. In contrast, E. huxleyi containing long-chain (31 and 33 carbon atoms) alkenes and very long-chain (37 to 39 carbon atoms) alkenones, in addition to phospholipids and glycolipids, generated a high yield of n-alkanes of various lengths (n-tridecane to n-pentatriacontane). The gas chromatography-mass spectrometry (GC-MS) profiles of these n-alkanes were similar to those of native petroleum crude oils despite containing a considerable amount of n-hentriacontane. The ratio of phytane to n-octadecane was also similar to that of native crude oils. PMID:23183975

  1. Euglena mitochondria and chloroplasts form tyrosine-O-sulfate

    Energy Technology Data Exchange (ETDEWEB)

    Saidha, T.; Hanfstingl, U.; Schiff, J.A. (Brandeis Univ., Waltham, MA (USA))

    1989-04-01

    Mitochondria from light-grown wild-type Euglena gracilis var. bacillaris Cori or dark-grown mutant W{sub 10}BSmL incubated with {sup 35}SO{sub 4}{sup 2{minus}} and ATP, or with {sup 14}C-tyrosine, non-radioactive sulfate and ATP accumulate a labeled compound in the medium. Since this compound shows exact coelectrophoresis with tyrosine-O-sulfate (TOS) at pH 2.0, 5.8 or 8.0., yields sulfate and tyrosine on acid hydrolysis, and treatment with aryl sulfatase from Aerobacter aerogenes yields sulfate and tyrosine but no tyrosine methyl ester, it is identified as TOS. No TOS is found outside purified developing chloroplasts incubated with {sup 35}SO{sub 4}{sup 2{minus}} and ATP, but both chloroplasts and mitochondria form to {sup 35}S externally when incubated with adenosine 3{prime} phosphate 5{prime}phospho({sup 35}S) sulfate (PAP{sup 35}S). Since no tyrosine need be added, tyrosine is provided from endogenous sources. Although TOS is found in the free pool of Euglena cells it cannot be detected in proteins of cells or mucus ruling our sulfation of tyrosine of protein or incorporation of TOS into proteins. The system forming TOS is membrane-bound and may be involved in tyrosine transport.

  2. Comparative toxicity of water soluble fractions of four oils on the growth of a Microalga

    Digital Repository Service at National Institute of Oceanography (India)

    Phatarpekar, P.V.; Ansari, Z.A.

    Toxic effects of water soluble fractions (WSF) of four different fuel oils on a microalga. Tetraselmis gracilis, were examined and compared. On applying different concentrations of WSF, a decrease in cell population was observed. Depending...

  3. Copper and Cadmium Toxicity to Marine Phytoplankton, Chaetoceros gracilis and Isochrysis sp.

    Directory of Open Access Journals (Sweden)

    Suratno Suratno

    2015-07-01

    Full Text Available In Copper (Cu based antifouling (AF paints Cu was largely used as booster biocide after organotin was banned. Cu is micronutrient which is important in photosynthesis process because Cu is an essential metal as component of enzyme and electron transport chain. But in certain dosage, Cu could be toxic to marine organism. Chaetoceros gracilis and Isochrysis sp. are dominant microalgae in aquatic ecosystem. In this study the effect of Cu and Cadmium (Cd on two marine microalgae, C. gracilis and Isochrysis sp. were compared. Toxicity test was based on American Standard for Testing Material (ASTM. IC50-96 h of Cd as reference toxicant was 2,370 mg.L-1 for C. gracilis and 490 mg.L-1 for Isochrysis sp. IC50-96 h of Cu to growth of C. gracilis was 63.75 mg.L-1 and Isochrysis sp. was 31.80 mg.L-1. Both Cd and Cu were inhibited growth of microalgae. Based on IC50-96 h value, it could be concluded that Cu was more toxic than Cd. Toxicity of Cu was 37 times stronger than Cd for C. gracilis and 15 times for Isochrysis sp. It was estimated that at concentration 10 mg.L-1 Cu does not show observable effect (NOEC to C. gracilis and 5 mg.L-1 to Isochrysis sp. The lowest observable effect of Cu (LOEC to C. gracilis was at concentration 17 mg.L-1 and 10 mg.L-1 for Isochrysis sp.

  4. Ankistrodesmus gracilis (Chlorophyta fertilized in swine manure in the laboratory

    Directory of Open Access Journals (Sweden)

    Lúcia Helena Sipaúba-Tavares

    2008-03-01

    Full Text Available The objective of the present work was to investigate the influence of swine manure media on the growth, total length, dry weight, and nutritional value of Ankistrodesmus gracilis microalgae. Two media were measured: “in natura” and biodigested. The growth rate peak for A. gracilis was highest with biodigester treatment (6.2 x 107 cells.mL-1 on the 5th day, at a volume of 2L. The highest percentage of lipids was verifi ed for “in natura” media. Protein was highest (p > 0.05 for the biodigested media at 2L. Biovolume, ash rate, and total length were different (p 0.05. Light demand was also different between media, with lesser intensity being required for biodigested media (13.5μE.cm-2.s-1. In fact, the biodigested media proved to be cheaper in terms of cost and benefit. Generally, the medium containing swine manure, both “in natura” and biodigested, showed better results in A. gracilis development, with water quality adequate for culture systems. Swine manure in both forms may also be used in high-density cultures in the laboratory.

  5. Muscle conserving free gracilis transfer (mini-gracilis free flap

    Directory of Open Access Journals (Sweden)

    Bibhuti Bhusan Nayak

    2012-01-01

    Full Text Available Gracilis is a commonly used muscle for free tissue transfer. It is also split into two based on its pedicles and used as two units. Use of distal part as a free flap in isolation has never been described in literature. We describe a technique of harvesting a small unit of gracilis based on its minor pedicle and maintaining the continuity and conserving the major bulk of muscle. Thus, the function of the muscle is preserved and the same is also available for transfer on its major pedicle later, if required.

  6. The use of radioactive precursors for the labeling of ribosomal proteins in Euglena

    International Nuclear Information System (INIS)

    Freyssinet, Georges

    1977-01-01

    The metabolism of three radioactive compounds has been studied in Euglena gracilis, either in the dark during the non-growing phase, or during light-induced greening, in the presence or absence of inhibitors of protein synthesis. The results can be summarized as follows: the fixation of 14 CO 2 and its incorporation into proteins occurs rapidly. Their intensities depend on the time of incubation and the physiological state of cells. Radioactive amino acids penetrate the cells within 2-4 hours and incorporation into proteins follows the uptake. In a few cases, amino acid uptake is low or even nonexistent. The rates of uptake and incorporation of radioactive sodium sulfate depend on the sulfur deficiency induced during growth in the dark, and on the time of incubation. Protein synthesis inhibitors act either on uptake or on incorporation or on both. The rate of inhibition depends on the inhibitor and precursor used. The radioactive precursors can be used for the labeling of cytoplasmic and chloroplast ribosomal proteins. The most favourable conditions for this labeling are mostly related to the uptake and incorporation measured on whole cells. All these results allow criteria to be determined which facilitate the choice of inhibitors, precursors and conditions of incubation depending on the protein studied

  7. Effect of Cadmium on the population growth of the marine diatom Chaetoceros gracilis Schutt

    Directory of Open Access Journals (Sweden)

    Giovana Vera

    2014-06-01

    Full Text Available Phytoplankton constitutes the base of the trophic webs in the marine environment, so it is important to know the possible effects of pollutants on the algal populations. In the present paper the effect of cadmium on the population growth of the diatom Chaetoceros gracilis was assessed. The microalgae were cultured in the a modified “f/2” Guillard medium, and were exposed to different concentrations of cadmium between 50 and 100000 µg.–1, which produced an inhibitory effect from 20% to 99% on the population growth of Chaetoceros gracilis. Based on the dose (cadmium-response (inhibition relationship, a mean effective concentration (EC50% equal to 591 µg.L–1 of cadmium was obtained.

  8. 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.

  9. Membrane skeletal proteins and their integral membrane protein anchors are targets for tyrosine and threonine kinases in Euglena.

    Science.gov (United States)

    Fazio, M J; Da Silva, A C; Rosiere, T K; Bouck, G B

    1995-01-01

    Proteins of the membrane skeleton of Euglena gracilis were extensively phosphorylated in vivo and in vitro after incubation with [32P]-orthophosphate or gamma-[32P] ATP. Endogenous protein threonine/serine activity phosphorylated the major membrane skeletal proteins (articulins) and the putative integral membrane protein (IP39) anchor for articulins. The latter was also the major target for endogenous protein tyrosine kinase activity. A cytoplasmic domain of IP39 was specifically phosphorylated, and removal of this domain with papain eliminated the radiolabeled phosphoamino acids and eliminated or radically shifted the PI of the multiple isoforms of IP39. In gel kinase assays IP39 autophosphorylated and a 25 kDa protein which does not autophosphorylate was identified as a threonine/serine (casein) kinase. Plasma membranes from the membrane skeletal protein complex contained threonine/serine (casein) kinase activity, and cross-linking experiments suggested that IP39 was the likely source for this membrane activity. pH optima, cation requirements and heparin sensitivity of the detergent solubilized membrane activity were determined. Together these results suggest that protein kinases may be important modulators of protein assembly and function of the membrane skeleton of these protistan cells.

  10. Immunomodulation of rainbow trout (Oncorhynchus mykiss) fry by bath exposure to a β-glucan from Euglena gracilis

    DEFF Research Database (Denmark)

    Chettri, Jiwan Kumar; Kania, Per Walter; Buchmann, Kurt

    2013-01-01

    Early developmental stages of fish mostly depend on innate immune factors for their protection. Augmenting these factors by application of different immunostimulatory substances may be beneficial for rearing and survival of the early life stages of fish. Bath administration of stimulants leads to...

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

    Directory of Open Access Journals (Sweden)

    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

  12. Cultivo de Ankistrodesmus gracilis (Chlorophyta em laboratório à base de esterco suíno

    Directory of Open Access Journals (Sweden)

    Tatiana Betioli Fioresi

    2008-01-01

    Full Text Available http://dx.doi.org/10.5007/2175-7925.2008v21n1p7 O objetivo do presente trabalho foi testar a influência do meio à base de esterco suíno “in natura” e biodigerido, sobre o desenvolvimento, crescimento, comprimento total, peso seco e valor nutricional da microalga Ankistro desmus gracilis. O pico de crescimento para A. gracilis foi maior no meio biodigerido (6,2 x 107 células. mL-1 no volume de 2L. Alta porcentagem de lipídio foi observada no meio “in natura”, e, elevados teores de proteína no meio biodigerido em 2L. O biovolume, teor de cinzas e comprimento total foram diferentes (p 0,05. O requerimento de luz foi diferente entre os meios, com menor intensidade para o esterco biodigerido (13,5μE.cm-2.s-1, indicando menor custo benefício. O meio a base de esterco suíno, mostrou bons resultados para o crescimento de A. gracilis, com qualidade de água adequada para cultivo, podendo ser utilizado para cultura em larga escala.

  13. Carrying capacity of Chaetoceros gracilis in Homa Lagoon and the ...

    African Journals Online (AJOL)

    The possibility for nutrient limitation to affect C. gracilis was assessed from two different ecosystems (Izmir Bay and Homa Lagoon). Our goal was to determine the growth rate of all nutrients and the maximum levels of the C. gracilis phytoplankton biomass (the maximum biomass carrying capacity) on the extent of its full ...

  14. Modeling and Control of Algae Harvesting, Dewatering and Drying (HDD) Systems

    Science.gov (United States)

    2012-05-01

    concentration to 5% water based on latent heat of vaporization Algae Botryococcus braunii Chlorella vulgaris Euglena gracilis Nannochlorops is...microalga Chlorella protothecoides by heterotrophic growth in fermenters. J Biotechnol 126:499–507, 2006 [9] Acièn Fernández F-G, Garcìa Camacho F

  15. 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.

  16. Campylobacter gracilis and Campylobacter rectus in primary endodontic infections.

    Science.gov (United States)

    Siqueira, J F; Rôças, I N

    2003-03-01

    A species-specific nested polymerase chain reaction (PCR) assay was used to investigate the occurrence of Campylobacter gracilis and C. rectus in primary root canal infections. Samples were collected from 57 single-rooted teeth with carious lesions, necrotic pulps and radiographic evidence of periradicular disease. Twenty-eight cases were diagnosed as chronic asymptomatic periradicular lesions, 12 cases as acute apical periodontitis, and 17 cases as acute periradicular abscess. DNA was extracted from the samples and initially amplified using universal 16S rDNA primers. A second round of amplification using the first PCR products was performed to specifically detect C. gracilis or C. rectus in the samples. Campylobacter gracilis and C. rectus were, respectively, detected in 21.4 (6 of 28) and 30% (6 of 20) of the root canals associated with chronic asymptomatic periradicular lesions. Campylobacter gracilis was found in 16.7% (2 of 12) of the cases diagnosed as acute apical periodontitis, whilst C. rectus was found in 33.3% (two of six cases). In the abscessed cases, C. gracilis and C. rectus were detected in 23.5 (4 of 17) and 11.8% (2 of 17) of the cases, respectively. No association of these species with clinical symptoms was observed (P > 0.01) In general, species-specific nPCR allowed the detection of C. gracilis in 21.1% (12 of 57) and C. rectus in 23.3% (10 of 43)of the samples taken from primary endodontic infections. Findings confirmed the assertion that both C. gracilis and C. rectus participate in infections of endodontic origin and suggest a pathogenetic role with regard to periradicular diseases.

  17. Biotechnological applications of microalgae

    OpenAIRE

    Wan-Loy Chu

    2012-01-01

    Microalgae are important biologicalresources that have a wide range of biotechnologicalapplications. Due to their high nutritional value,microalgae such as Spirulina and Chlorella are beingmass cultured for health food. A variety of high-valueproducts including polyunsaturated fatty acids (PUFA),pigments such as carotenoids and phycobiliproteins, andbioactive compounds are useful as nutraceuticals andpharmaceuticals, as well as for industrial applications. Interms of environmental biotechnolo...

  18. Pedicularis gracilis Wall. Ex Benth. (Scrophulariaceae Complex in the Himalayas – A Taxonomic Reinvestigation

    Directory of Open Access Journals (Sweden)

    Tariq Husain

    2003-03-01

    Full Text Available The paper highlights the complex nature of Pedicularis gracilis Wall. ex Benth. in the Himalayas and enumerates two subspecies and four varieties of this species. Morphological and distributional data have been appended to show that the subspecies – gracilis and brunoniana (Wall. ex Pennell Husain & Garg and varieties – gracilis and stricta (Wall. Husain & Garg (under subsp. gracilis and brunoniana and macrocarpa (Prain Husain & Garg (under subsp. brunoniana are distinct.

  19. Impact of elevated CO2 concentrations on the growth and ultrastructure of non-calcifying marine diatom (Chaetoceros gracilis F.Schütt

    Directory of Open Access Journals (Sweden)

    Hanan M. Khairy

    2014-01-01

    Full Text Available The impacts of different CO2 concentrations on the growth, physiology and ultrastructure of noncalcifying microalga Chaetoceros gracilis F.Schütt (Diatom were studied. We incubated Ch. gracilis under different CO2 concentrations, preindustrial and current ambient atmospheric concentrations (285 and 385 μatm, respectively or predicted year-2100 CO2 levels (550, 750 and 1050 μatm in continuous culture conditions. The growth of Ch. gracilis measured as cell number was decreased by increasing the pCO2 concentration from nowadays concentration (385 μatm to 1050 μatm. The lowest percentage changes of oxidizable organic matter, nitrite, nitrate, phosphate and silicate were recorded at a higher pCO2 (1050 μatm, and this is in consistence with the lowest recorded cell number indicating unsuitable conditions for the growth of Ch. gracilis. The minimum cell numbers obtained at higher levels of CO2 clearly demonstrate that, low improvement occurred when the carbon level was raised. This was confirmed by a highly negative correlation between cell number and carbon dioxide partial pressure (r = −0.742, p ⩽ 0.05. On the other hand, highest growth rate at pCO2 = 385 μatm was also confirmed by the maximum uptake of nutrient salts (NO3 = 68.96 μmol.l−1, PO4 = 29.75 μmol.l−1, Si2O3 = 36.99 μmol.l−1. Total protein, carbohydrate and lipid composition showed significant differences (p ⩽ 0.05 at different carbon dioxide concentrations during the exponential growth phase (day 8. Transmission Electron Microscopy of Ch. gracilis showed enlargement of the cell, chloroplast damage, disorganization and disintegration of thylakoid membranes; cell lysis occurs at a higher CO2 concentration (1050 μatm. It is concluded from this regression equation and from the results that the growth of Ch. gracilis is expected to decrease by increasing pCO2 and increasing ocean acidification.

  20. Speciation of bioaccumulated uranium(VI) by Euglena mutabilis cells obtained by laser fluorescence spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Brockmann, Sina; Bernhard, Gert [Technical Univ. Dresden (Germany). Radiochemistry; Helmholtz-Zentrum Dresden-Rossendorf (HZDR) e.V., Dresden (Germany). Inst. of Resource Ecology; Arnold, Thuro [Helmholtz-Zentrum Dresden-Rossendorf (HZDR) e.V., Dresden (Germany). Inst. of Resource Ecology

    2014-07-01

    The ability of Euglena mutabilis cells - a unicellular protozoan with a flexible pellicle, which is typically found in acid mine drainage (AMD) environments - to bioaccumulate uranium under acid conditions was studied in batch sorption experiments at pH 3 and 4 using Na{sub 2}SO{sub 4} and NaClO{sub 4} as background media. It was found that axenic cultures of Euglena mutabilis Schmitz were able to bioaccumulate in 5 days 94.9 to 99.2% of uranium from a 1 x 10{sup -5} mol/L uranium solution in perchlorate medium and 95.1 to 95.9% in sodium sulfate medium, respectively. The speciation of uranium in solution and uranium bioaccumulated by Euglena mutabilis cells, were studied by laser induced fluorescence spectroscopy (LIFS). The LIFS investigations showed that the uranium speciation in the NaClO{sub 4} systems was dominated by free uranyl(VI) species and that the UO{sub 2}SO{sub 4} species was dominating in the Na{sub 2}SO{sub 4} medium. Fluorescence spectra of the bioaccumulated uranium revealed that aqueous uranium binds to carboxylic and/or (organo)phosphate groups located on the euglenid pellicle or inside the Euglena mutabilis cells. Reduced uranium immobilization rates of 0.93-1.43 mg uranium per g Euglena mutabilis biomass were observed in similar experiments, using sterile filtrated AMD waters containing, 4.4 x 10{sup -5} mol/L uranium. These lower rates were attributed to competition with other cations for available sorption sites. Additional LIFS measurements, however, showed that the speciation of the bioaccumulated uranium by the Euglena mutabilis cells was found to be identical with the uranium speciation found in the bioaccumulation experiments carried out in Na{sub 2}SO{sub 4} and NaClO{sub 4} media. The results indicate that Euglena mutabilis has the potential to immobilize aqueous uranium under acid condition and thus may be used in future as promising agent for immobilizing uranium in low pH waste water environments. (orig.)

  1. Speciation of bioaccumulated uranium(VI) by Euglena mutabilis cells obtained by laser fluorescence spectroscopy

    International Nuclear Information System (INIS)

    Brockmann, Sina; Bernhard, Gert; Helmholtz-Zentrum Dresden-Rossendorf; Arnold, Thuro

    2014-01-01

    The ability of Euglena mutabilis cells - a unicellular protozoan with a flexible pellicle, which is typically found in acid mine drainage (AMD) environments - to bioaccumulate uranium under acid conditions was studied in batch sorption experiments at pH 3 and 4 using Na 2 SO 4 and NaClO 4 as background media. It was found that axenic cultures of Euglena mutabilis Schmitz were able to bioaccumulate in 5 days 94.9 to 99.2% of uranium from a 1 x 10 -5 mol/L uranium solution in perchlorate medium and 95.1 to 95.9% in sodium sulfate medium, respectively. The speciation of uranium in solution and uranium bioaccumulated by Euglena mutabilis cells, were studied by laser induced fluorescence spectroscopy (LIFS). The LIFS investigations showed that the uranium speciation in the NaClO 4 systems was dominated by free uranyl(VI) species and that the UO 2 SO 4 species was dominating in the Na 2 SO 4 medium. Fluorescence spectra of the bioaccumulated uranium revealed that aqueous uranium binds to carboxylic and/or (organo)phosphate groups located on the euglenid pellicle or inside the Euglena mutabilis cells. Reduced uranium immobilization rates of 0.93-1.43 mg uranium per g Euglena mutabilis biomass were observed in similar experiments, using sterile filtrated AMD waters containing, 4.4 x 10 -5 mol/L uranium. These lower rates were attributed to competition with other cations for available sorption sites. Additional LIFS measurements, however, showed that the speciation of the bioaccumulated uranium by the Euglena mutabilis cells was found to be identical with the uranium speciation found in the bioaccumulation experiments carried out in Na 2 SO 4 and NaClO 4 media. The results indicate that Euglena mutabilis has the potential to immobilize aqueous uranium under acid condition and thus may be used in future as promising agent for immobilizing uranium in low pH waste water environments. (orig.)

  2. Outcomes of electrically stimulated gracilis neosphincter surgery.

    Science.gov (United States)

    Tillin, T; Chambers, M; Feldman, R

    2005-07-01

    To examine patient quality of life (QoL) and long-term costs of electrically stimulated gracilis neosphincter surgery (ESGNS). Independently conducted prospective case-comparison study of patients at the Royal London Hospital (RLH), plus a cross-sectional study of outcomes of ESGNS performed at three other UK centres. Cases were patients who underwent ESGNS at the participating hospitals during a 5-year period from 1977. Comparisons were made with two groups of people with similar bowel disorders who did not undergo ESGNS. ESGNS is a procedure designed to improve bowel function for people living with severe faecal incontinence or stomas. It involves transposition of the gracilis muscle to form a neo-anal sphincter. The transposed muscle is electrically stimulated via an electronic pulse generator implanted beneath the skin of the abdomen. Clinical success and symptomatic outcomes of surgery. Generic, domain and condition specific measures of QoL. Comparative costs to the NHS of ESGNS and conventional alternatives. At 3 years after surgery approximately three-quarters of patients still had functioning neosphincters. At this stage, bowel-related QoL and continence improved by more than 20% for nearly two-thirds of RLH patients. However, ongoing bowel evacuation difficulties occurred in half of those with good continence outcomes. QoL improvements were maintained in the smaller group of RLH patients who had reached 4 and 5 years of follow-up, although at this stage the proportion with failed neosphincters had increased. The RLH findings were supported by those from the three other UK centres. No significant changes in QoL were observed in the comparison groups during the follow-up period. The mean cost of patient care at RLH, was 23,253 pounds. In the other three centres, the estimated mean cost of the intervention per patient was 11,731 pounds, reflecting fewer planned operations and repeat admissions. Costs of patient care for those with stomas who did not undergo

  3. 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.

  4. 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

  5. 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

  6. Economics of microalgae production

    NARCIS (Netherlands)

    Acién, F.G.; Molina, E.; Fernández-Sevilla, J.M.; Barbosa, M.; Gouveia, L.; Sepúlveda, C.; Bazaes, J.; Arbib, Z.

    2017-01-01

    The economic analysis of biomass production is a critical step in ensuring the success of any microalgae-based industry. Until recently, only small-scale facilities of less than 10. ha have been in operation, but now large-scale facilities of more than 200. ha are being built and operated.

  7. Food commodities from microalgae

    NARCIS (Netherlands)

    Draaisma, R.B.; Wijffels, R.H.; Slegers, P.M.; Brentner, L.B.; Roy, A.; Barbosa, M.J.

    2013-01-01

    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

  8. 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

  9. 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...

  10. 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.

  11. 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

  12. Multi-Product Microalgae Biorefineries

    NARCIS (Netherlands)

    Lam, 't G.P.; Vermuë, M.H.; Eppink, M.H.M.; Wijffels, R.H.; Berg, van den C.

    2018-01-01

    Although microalgae are a promising biobased feedstock, industrial scale production is still far off. To enhance the economic viability of large-scale microalgae processes, all biomass components need to be valorized, requiring a multi-product biorefinery. However, this concept is still too

  13. On the chemical identification and visualization of uranium species in biofilms and Euglena mutabilis cells

    International Nuclear Information System (INIS)

    Brockmann, Sina

    2013-01-01

    For risk assessment of anthropogenic uranium contaminations in the environment a detailed knowledge of the migration and immobilization behavior is required to prevent health hazards for humans and animals caused by an uncontrolled discharge of uranium. Hence, comprehensive studies on the interactions of uranium with the environment are required. Besides the influences of the geological materials, there is a huge effect of the biosphere, especially the interactions with microorganisms and biofilms, on the properties of uranium in the environment. The aim of this study was to investigate and to describe naturally occurring biofilms from real uranium contaminated areas and their influence on the uranium migration. The investigations in this study on the localization and the speciation of the uranium in the biosystems were primarily done with a coupled system of laser scanning microscopy (CLSM) and laser induced fluorescence spectroscopy (LIFS). Natural biofilms collected from two uranium contaminated acid mine drainage (AMD) environments, the former uranium mine in Koenigstein (Saxony, Germany) and the former Gessenheap near Ronneburg (Thuringia,Germany), were investigated in this study. The chosen samples represent typical biofilm communities living in AMD water and are exemplary for potentially occurring scenarios of contaminated mining water both in the underground and on the surface. The investigation on the interactions between uranium and Euglena mutabilis, which is a typical unicellular microorganism that can be found in acidic, uranium and other heavy metal containing waters, was another important part of this study. Bioaccumulation experiments of uranium on living Euglena mutabilis cells depending on the pH (pH 3 - 6) and on the background media in sodium perchlorate (9 g/l) or sodium sulfate (3.48 g/l) solution containing 0.01 mM uranium show an effective immobilization of uranium. At the acidic pH-values (pH 3 - 4) over 90 % of the added uranium was

  14. 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.

  15. 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.

  16. Physicochemical analysis of cellulose from microalgae ...

    African Journals Online (AJOL)

    African Journal of Biotechnology ... Nannochloropsis gaditana is a microalgae belonging to the class of Eustigmatophyceae. This particular microalga is the most studied species. For its richness in lipids, it is used for the biodiesel production.

  17. Microalgae harvesting techniques: A review.

    Science.gov (United States)

    Singh, Gulab; Patidar, S K

    2018-07-01

    Microalgae with wide range of commercial applications have attracted a lot of attention of the researchers in the last few decades. However, microalgae utilization is not economically sustainable due to high cost of harvesting. A wide range of solid - liquid separation techniques are available for microalgae harvesting. The techniques include coagulation and flocculation, flotation, centrifugation and filtration or a combination of various techniques. Despite the importance of harvesting to the economics and energy balance, there is no universal harvesting technique for microalgae. Therefore, this review focuses on assessing technical, economical and application potential of various harvesting techniques so as to allow selection of an appropriate technology for cost effectively harvesting of microalgae from their culture medium. Various harvesting and concentrating techniques of microalgae were reviewed to suggest order of suitability of the techniques for four main microalgae applications i.e biofuel, human and animal food, high valued products, and water quality restoration. For deciding the order of suitability, a comparative analysis of various harvesting techniques based on the six common criterions (i.e biomass quality, cost, biomass quantity, processing time, species specific and toxicity) has been done. Based on the order of various techniques vis-a-vis various criteria and preferred order of criteria for various applications, order of suitability of harvesting techniques for various applications has been decided. Among various harvesting techniques, coagulation and flocculation, centrifugation and filtration were found to be most suitable for considered applications. These techniques may be used alone or in combination for increasing the harvesting efficiency. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. Recovery from inhibition of transcription in γ-irradiated Euglena cells

    International Nuclear Information System (INIS)

    Tsushimoto, G.; Kikuchi, T.; Ishida, M.R.

    1982-01-01

    Transcriptional activity was inhibited with low doses of γ-irradiation which did not cause the death of cells, but induced the delay of cell division in the unicellular alga Euglena. The incorporation of [ 14 C]uracil into cells was inhibited to about 50% of non-irradiated cells immediately after 3 krad irradiation. The suppressed transcriptional activity was gradually recovered after irradiation. At about 12 h post-irradiation, the rate of incorporation of [ 14 C]uracil recovered to that of non-irradiated cells. The synthesis of ribosomal RNA was inhibited immediately after 3 krad irradiation, but it recovered within 12 h after irradiation. The synthesis of cytosol ribosomal RNA precursor was more strongly inhibited than that of other cytosol ribosomal RNAs. The synthesis of cytoplasmic organelle ribosomal RNA was also inhibited and recovered after 3 krad irradiation. (Auth.)

  19. 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.

  20. Heavy metal sorption by microalgae

    International Nuclear Information System (INIS)

    Sandau, E.; Sandau, P.; Pulz, O.

    1996-01-01

    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.)

  1. Phosphopantetheinylation in the green microalgae Chlamydomonas reinhardtii

    DEFF Research Database (Denmark)

    Sonnenschein, Eva; Pu, Yuan; Beld, Joris

    2016-01-01

    available microalgal genome data revealed that most green microalgae appear to carry two PPTases forming clusters with each C. reinhardtii PPTase, while microalgae of other divisions carry one or two PPTases and do not cluster in the pattern of the green algal data. This new understanding on the PPTases...... in microalgae shows that microalgae are already primed for biotechnological applications in contrast to other organisms. Thus, microalgae have great potential for metabolic engineering efforts in the realm of biofuel and high-value products including direct engineering of the fatty acid or secondary metabolism...

  2. Airborne Microalgae: Insights, Opportunities, and Challenges

    Science.gov (United States)

    Skjøth, Carsten Ambelas; Šantl-Temkiv, Tina; Löndahl, Jakob

    2016-01-01

    Airborne dispersal of microalgae has largely been a blind spot in environmental biological studies because of their low concentration in the atmosphere and the technical limitations in investigating microalgae from air samples. Recent studies show that airborne microalgae can survive air transportation and interact with the environment, possibly influencing their deposition rates. This minireview presents a summary of these studies and traces the possible route, step by step, from established ecosystems to new habitats through air transportation over a variety of geographic scales. Emission, transportation, deposition, and adaptation to atmospheric stress are discussed, as well as the consequences of their dispersal on health and the environment and state-of-the-art techniques to detect and model airborne microalga dispersal. More-detailed studies on the microalga atmospheric cycle, including, for instance, ice nucleation activity and transport simulations, are crucial for improving our understanding of microalga ecology, identifying microalga interactions with the environment, and preventing unwanted contamination events or invasions. PMID:26801574

  3. Antiviral Ability of Kalanchoe gracilis Leaf Extract against Enterovirus 71 and Coxsackievirus A16

    Directory of Open Access Journals (Sweden)

    Ching-Ying Wang

    2012-01-01

    Full Text Available Pandemic infection or reemergence of Enterovirus 71 (EV71 and coxsackievirus A16 (CVA16 occurs in tropical and subtropical regions, being associated with hand-foot-and-mouth disease, herpangina, aseptic meningitis, brain stem encephalitis, pulmonary edema, and paralysis. However, effective therapeutic drugs against EV71 and CVA16 are rare. Kalanchoe gracilis (L. DC is used for the treatment of injuries, pain, and inflammation. This study investigated antiviral effects of K. gracilis leaf extract on EV71 and CVA16 replications. HPLC analysis with a C-18 reverse phase column showed fingerprint profiles of K. gracilis leaf extract had 15 chromatographic peaks. UV/vis absorption spectra revealed peaks 5, 12, and 15 as ferulic acid, quercetin, and kaempferol, respectively. K. gracilis leaf extract showed little cytotoxicity, but exhibited concentration-dependent antiviral activities including cytopathic effect, plaque, and virus yield reductions. K. gracilis leaf extract was shown to be more potent in antiviral activity than ferulic acid, quercetin, and kaempferol, significantly inhibiting in vitro replication of EV71 (IC50=35.88 μg/mL and CVA16 (IC50=42.91 μg/mL. Moreover, K. gracilis leaf extract is a safe antienteroviral agent with the inactivation of viral 2A protease and reduction of IL-6 and RANTES expressions.

  4. Antibacterial and Antioxidant Activity of Green Algae Halimeda gracilis from Seribu Island District

    Directory of Open Access Journals (Sweden)

    Abdul Basir

    2017-08-01

    Full Text Available Seaweeds have ecological functions as primary producers in marine waters. It also has an important economic value as a producer of hydrocolloids (alginate, agar and carrageenan that is used in various industries of food and pharmaceuticals. This study aimed to determine the antibacterial and antioxidant activity of green algae Halimeda gracilis. The study was conducted in several stages, sample collection and preparation, extraction of bioactive compound, fractionation, antibacterial and antioxidant test, and phytochemical. Extraction was done by maceration method using methanol and concentrated by rotary evaporator. The methanol extracts of H. gracilis were tested against Staphylococcus aureus and Escherichia coli. Methanol extract of H. gracilis formed inhibition zone against the test bacteria with diameter of inhibition zone was 10 mm and 6 mm, respectively. After liquid-liquid partition (water: ethyl acetate, inhibition zone was only seen in the ethyl acetate fraction of H. gracilis with diameter of inhibition zone was 6 mm and 7.50±1.71 mm, respectively. Antioxidant test methanol extracts and ethyl acetate fractions of H. gracilis each show IC50 value of 290.49 ppm and 375.50 ppm. Phytochemical test showed methanol extract of H. gracilis contains phenols and steroids.

  5. Antiviral Ability of Kalanchoe gracilis Leaf Extract against Enterovirus 71 and Coxsackievirus A16

    Science.gov (United States)

    Wang, Ching-Ying; Huang, Shun-Chueh; Zhang, Yongjun; Lai, Zhen-Rung; Kung, Szu-Hao; Chang, Yuan-Shiun; Lin, Cheng-Wen

    2012-01-01

    Pandemic infection or reemergence of Enterovirus 71 (EV71) and coxsackievirus A16 (CVA16) occurs in tropical and subtropical regions, being associated with hand-foot-and-mouth disease, herpangina, aseptic meningitis, brain stem encephalitis, pulmonary edema, and paralysis. However, effective therapeutic drugs against EV71 and CVA16 are rare. Kalanchoe gracilis (L.) DC is used for the treatment of injuries, pain, and inflammation. This study investigated antiviral effects of K. gracilis leaf extract on EV71 and CVA16 replications. HPLC analysis with a C-18 reverse phase column showed fingerprint profiles of K. gracilis leaf extract had 15 chromatographic peaks. UV/vis absorption spectra revealed peaks 5, 12, and 15 as ferulic acid, quercetin, and kaempferol, respectively. K. gracilis leaf extract showed little cytotoxicity, but exhibited concentration-dependent antiviral activities including cytopathic effect, plaque, and virus yield reductions. K. gracilis leaf extract was shown to be more potent in antiviral activity than ferulic acid, quercetin, and kaempferol, significantly inhibiting in vitro replication of EV71 (IC50 = 35.88 μg/mL) and CVA16 (IC50 = 42.91 μg/mL). Moreover, K. gracilis leaf extract is a safe antienteroviral agent with the inactivation of viral 2A protease and reduction of IL-6 and RANTES expressions. PMID:22666293

  6. Development of virtual photobioreactor for microalgae culture considering turbulent flow and flashing light effect

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Toru; Hirabayashi, Shinichiro [Department of Ocean Technology, Policy, and Environment, University of Tokyo, 5-1-5 Kashiwa-no-ha, Kashiwa 277-8563 (Japan); Yamada, Daiki [Department of Systems Innovation, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8563 (Japan)

    2010-06-15

    A virtual photobioreactor for mass-culturing microalgae was developed. This is a computer model system combining a numerical simulation code for two-phase turbulent flow of bubbles and continuous medium and a photosynthesis model that can express the flashing light effect. The flashing light effect should be considered because turbulent flow in the reactor gives microalgae a chance to come close to the irradiated surface in the opaque medium at irregular frequency and this intermittent illumination enhances photosynthesis of the algae. The two-phase flow model output the time history of light pass along light ray between the irradiated wall surface of the reactor and the individual algal cell, which was passively moved by turbulent flow. When the history of light intensity, which was calculated from that of the light pass and the Beer-Lambert law, experienced by the cell was given, the photosynthesis model output the amount of O{sub 2} emitted from the cell in every small time interval. Finally, the harvest of the alga was estimated from the amount of the O{sub 2}. As a result, the present model system successfully predicted the algal concentration optimal for the largest O{sub 2} emission at the given light intensity and simulated the growth curve of Chaetoceros gracili. (author)

  7. Development of virtual photobioreactor for microalgae culture considering turbulent flow and flashing light effect

    International Nuclear Information System (INIS)

    Sato, Toru; Yamada, Daiki; Hirabayashi, Shinichiro

    2010-01-01

    A virtual photobioreactor for mass-culturing microalgae was developed. This is a computer model system combining a numerical simulation code for two-phase turbulent flow of bubbles and continuous medium and a photosynthesis model that can express the flashing light effect. The flashing light effect should be considered because turbulent flow in the reactor gives microalgae a chance to come close to the irradiated surface in the opaque medium at irregular frequency and this intermittent illumination enhances photosynthesis of the algae. The two-phase flow model output the time history of light pass along light ray between the irradiated wall surface of the reactor and the individual algal cell, which was passively moved by turbulent flow. When the history of light intensity, which was calculated from that of the light pass and the Beer-Lambert law, experienced by the cell was given, the photosynthesis model output the amount of O 2 emitted from the cell in every small time interval. Finally, the harvest of the alga was estimated from the amount of the O 2 . As a result, the present model system successfully predicted the algal concentration optimal for the largest O 2 emission at the given light intensity and simulated the growth curve of Chaetoceros gracili.

  8. 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

  9. Antimicrobial action of the essential oil of Lippia gracilis Schauer

    Directory of Open Access Journals (Sweden)

    Cynthia Cavalcanti de Albuquerque

    2006-07-01

    Full Text Available Antimicrobial activity of the essential oil (EO of Lippia gracilis Schauer over fungi and heliconia endophytic bacteria was evaluated. For the fungi Geotrichum candidum; Trichoderma viride; Torula herbarum; Paecillomyces sp.; Fusicoccum sp.; P. aeruginens; Curvularia lunata; Aspergillus nidulans; A. flavus; and A. niger mycelial discs were inoculated in PDA medium with oil (0; 420; 440; 460; 480 e 500 µL L-1. The inhibition percentage in 420 µL L-1 was 100% for all fungi, except for C. lunata and A. niger, which was 95.58% and 89.40% , respectively. In other experiment, a suspension of the Salmonella choleraceuis-diarizonae, Enterobacter asburiae, Bacillus thuringiensis, B. pumilus, B. cereus, Klebsiella pneumoniae, and E. hormaechei was individually added to the solid NYDA medium dishes. In each dish, wells were drilled in medium and filled with water or EO (420 µL L-1. The diameter of the inhibition halo was assessed. K. pneumoniae was the bacterial species less sensitive and E. hormaechei was the most sensitive.Avaliou-se a atividade antimicrobiana do óleo essencial (OE de Lippia gracilis Schauer sobre fungos contaminantes de laboratórios de cultura de tecidos vegetais e bactérias endofíticas de helicônias. Discos de micélio dos fungos Geotrichum candidum; Trichoderma viride; Torula herbarum; Paecillomyces sp.; Aspergillus nidulans; Fusicoccum sp.; A. flavus; P. aeruginens; Curvularia lunata e A. niger, foram inoculados em meio BDA com óleo (0; 420; 440; 460; 480 e 500 µL L-1. O percentual de inibição em 420 µL L-1 foi de 100% para todos os fungos exceto paraC. lunata and A. niger, o qual foi de 95.58% and 89.40% respectivamente. Em outro experimento, suspensão das espécies Salmonela choleraceuis-diarizonae, Enterobacter asburiae, Bacillus thuringiensis, B. pumilus, Klebsiella pneumoniae, E. hormaechei, Bacillus pumilus, B. cereus, B. pumilus foi individualmente adicionada ao meio NYDA, que foi vertido em placas de Petri e, ap

  10. 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)

  11. Dynamic Penile Corpora Cavernosa Reconstruction Using Bilateral Innervated Gracilis Muscles: A Preclinical Investigation.

    Science.gov (United States)

    Yin, Zhuming; Liu, Liqiang; Xue, Bingjian; Fan, Jincai; Chen, Wenlin; Liu, Zheng

    2018-03-07

    Prosthesis-assisted penile reconstruction has been performed extensively to restore a cosmetically acceptable phallus. However, a large number of patients will undergo revision surgery for various prosthesis-related complications. To develop a 1-stage prosthesis-free dynamic cavernosa reconstruction method using bilateral innervated gracilis muscles and to investigate the feasibility and reliability of the surgical design. 10 fresh cadavers were dissected to assess the availability of bilateral gracilis muscles for functional cavernosa rebuilding. 11 mongrel female dogs were involved in the penile reconstruction surgery. The neophallus consisted of bilateral gracilis muscles as the neo-cavernosa, a right gracilis skin flap as the neourethra, and a lower abdominal flap with an anterior rectus sheath as the skin envelope and neo-tunica albuginea. The function and structure of the neo-phalli were assessed 7 months postoperatively. The neurovascular pedicle length of the gracilis muscles and the volume of the gracilis venter musculi were measured in the cadaveric investigation. The average dimensions of the canine neo-phalli at rest and during electrostimulated erection were obtained and the muscular fatigue-resistant curve was drawn. Histologic evaluations also were performed. The neurovascular pedicle length and volume of the gracilis muscles were sufficient to yield a nearly normal appearance of the neo-cavernosa in the cadaveric and animal studies. The muscular fatigue-resistant curve demonstrated adequate length, stiffness, and duration of erection of the neo-phalli to accomplish normal coitus. Histologic evaluations showed an intact neourethra and nearly normal muscle structure in the inner layer of the canine neo-cavernosa, except for significantly increased amount of collagen fibers and type I/III collagen ratio in the outer layer of the neo-cavernosa. The percentage of type II (fatigue-prone) muscle fibers did not change significantly. Our preclinical

  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. 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

  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. Biodiesel from microalgae beats bioethanol.

    Science.gov (United States)

    Chisti, Yusuf

    2008-03-01

    Renewable biofuels are needed to displace petroleum-derived transport fuels, which contribute to global warming and are of limited availability. Biodiesel and bioethanol are the two potential renewable fuels that have attracted the most attention. As demonstrated here, biodiesel and bioethanol produced from agricultural crops using existing methods cannot sustainably replace fossil-based transport fuels, but there is an alternative. Biodiesel from microalgae seems to be the only renewable biofuel that has the potential to completely displace petroleum-derived transport fuels without adversely affecting supply of food and other crop products. Most productive oil crops, such as oil palm, do not come close to microalgae in being able to sustainably provide the necessary amounts of biodiesel. Similarly, bioethanol from sugarcane is no match for microalgal biodiesel.

  16. Solar Radiation Stress in Natural Acidophilic Biofilms of Euglena mutabilis Revealed by Metatranscriptomics and PAM Fluorometry.

    Science.gov (United States)

    Puente-Sánchez, Fernando; Olsson, Sanna; Gómez-Rodriguez, Manuel; Souza-Egipsy, Virginia; Altamirano-Jeschke, Maria; Amils, Ricardo; Parro, Victor; Aguilera, Angeles

    2016-02-01

    The daily photosynthetic performance of a natural biofilm of the extreme acidophilic Euglena mutabilis from Río Tinto (SW, Spain) under full solar radiation was analyzed by means of pulse amplitude-modulated (PAM) fluorescence measurements and metatrascriptomic analysis. Natural E. mutabilis biofilms undergo large-scale transcriptomic reprogramming during midday due to a dynamic photoinhibition and solar radiation stress. Photoinhibition is due to UV radiation and not to light intensity, as revealed by PAM fluorometry analysis. In order to minimize the negative effects of solar radiation, our data supports the presence of a circadian rhythm in this euglenophyte that increases their opportunity to survive. Differential gene expression throughout the day (at 12:00, 20:00 and night) was monitored by massive Illumina parallel sequencing of metatranscriptomic libraries. The transcription pattern was altered in genes involved in Photosystem II stability and repair, UV damaged DNA repair, non-photochemical quenching and oxidative stress, supporting the photoinhibition detected by PAM fluorometry at midday. Copyright © 2016 Elsevier GmbH. All rights reserved.

  17. Hydrothermal liquefaction of Gracilaria gracilis and Cladophora glomerata macro-algae for biocrude production.

    Science.gov (United States)

    Parsa, Mehran; Jalilzadeh, Hamoon; Pazoki, Maryam; Ghasemzadeh, Reza; Abduli, MohammadAli

    2018-02-01

    The potential of Gracilaria gracilis (G. gracilis) and Cladophora glomerata (C. glomerata) macro-algae species harvested from Caspian Sea for biocrude oil production under Hydrothermal Liquefaction (HTL) reaction at 350 °C and 15 min has been investigated. Furthermore, the effect of using recycled aqueous phase as the HTL reaction solvent was studied. The biocrude yield for G. gracilis and C. glomerata was 15.7 and 16.9 wt%, respectively with higher heating value (HHV) of 36.01 and 33.06 MJ/kg. The sources of each existing component in bio-oil were identified by GC-MS based on their suggested reaction pathways. Moreover, after two series of aqueous solution recycling, experiments showed that the bio-oil yield significantly increased compared with the initial condition. This increasing directly relates with recovery of carbon content from the aqueous solution residue. Copyright © 2017. Published by Elsevier Ltd.

  18. On the chemical identification and visualization of uranium species in biofilms and Euglena mutabilis cells; Zur chemischen Identifizierung und Visualisierung von Uran-Spezies in Biofilmen und Euglena mutabilis Zellen

    Energy Technology Data Exchange (ETDEWEB)

    Brockmann, Sina

    2013-11-14

    For risk assessment of anthropogenic uranium contaminations in the environment a detailed knowledge of the migration and immobilization behavior is required to prevent health hazards for humans and animals caused by an uncontrolled discharge of uranium. Hence, comprehensive studies on the interactions of uranium with the environment are required. Besides the influences of the geological materials, there is a huge effect of the biosphere, especially the interactions with microorganisms and biofilms, on the properties of uranium in the environment. The aim of this study was to investigate and to describe naturally occurring biofilms from real uranium contaminated areas and their influence on the uranium migration. The investigations in this study on the localization and the speciation of the uranium in the biosystems were primarily done with a coupled system of laser scanning microscopy (CLSM) and laser induced fluorescence spectroscopy (LIFS). Natural biofilms collected from two uranium contaminated acid mine drainage (AMD) environments, the former uranium mine in Koenigstein (Saxony, Germany) and the former Gessenheap near Ronneburg (Thuringia,Germany), were investigated in this study. The chosen samples represent typical biofilm communities living in AMD water and are exemplary for potentially occurring scenarios of contaminated mining water both in the underground and on the surface. The investigation on the interactions between uranium and Euglena mutabilis, which is a typical unicellular microorganism that can be found in acidic, uranium and other heavy metal containing waters, was another important part of this study. Bioaccumulation experiments of uranium on living Euglena mutabilis cells depending on the pH (pH 3 - 6) and on the background media in sodium perchlorate (9 g/l) or sodium sulfate (3.48 g/l) solution containing 0.01 mM uranium show an effective immobilization of uranium. At the acidic pH-values (pH 3 - 4) over 90 % of the added uranium was

  19. 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

  20. 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.

  1. 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

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

    African Journals Online (AJOL)

    This review presents the current classification of biofuels, with special focus on microalgae and their applicability for the production of biodiesel. The paper considered issues related with the processing and culturing of microalgae, for not only those that are involved in biofuel production, but as well as the possibility of their ...

  3. 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.

  4. UV-B affects photosynthesis, ROS production and motility of the freshwater flagellate, Euglena agilis Carter

    Energy Technology Data Exchange (ETDEWEB)

    Kottuparambil, Sreejith [Institute of Green Environmental Research Center, University of Incheon, Incheon, 406 840 (Korea, Republic of); Shin, Woongghi [Department of Biology, Chungnam University, Daejeon, 306 764 (Korea, Republic of); Brown, Murray T. [School of Marine Science and Engineering, Plymouth University, Drake Circus, Plymouth PL4 8AA (United Kingdom); Han, Taejun, E-mail: hanalgae@hanmail.net [Institute of Green Environmental Research Center, University of Incheon, Incheon, 406 840 (Korea, Republic of); Department of Marine Science, University of Incheon, Incheon, 406 840 (Korea, Republic of)

    2012-10-15

    Highlights: Black-Right-Pointing-Pointer We proposed a hypothesis for the UV-B protective/adaptive mechanism in Euglena agilis. After moderate levels of UV-B radiation, ROS plays a signaling role to shut down photosynthetic system for protection against harmful UV radiation. Black-Right-Pointing-Pointer E. agilis exposed to excessive UV appears to become animal-like, investing all its stored energy into movement rather than into sustaining its photosynthetic machinery. Black-Right-Pointing-Pointer This adaptation allows E. agilis to avoid harmful UV and seek a safe place where the organism may regain its photosynthetic capacity for survival. - Abstract: The effects of ultraviolet B (UV-B; 295-320 nm) radiation on certain vital physiological (photosynthesis), biochemical (production of reactive oxygen species - ROS) and behavioral (motility and orientation) characteristics were investigated in the unicellular photoautotroph, Euglena agilis Carter. The photosynthetic performance of E. agilis was recorded after exposure of between 15 and 60 min followed by a period of recovery lasting 6-24 h under dim light (5-10 {mu}mol photons m{sup -2} s{sup -1}). The maximum quantum yield of PS II (F{sub v}/F{sub m}) was reduced to 65% and 14% of initial values immediately following 15 and 30 min UV-B exposure, but recovered to 100 and 86% of the initials, respectively. Values of rETR{sub max} in E. agilis exposed to 15 min UV-B were similar to those of the initials, but a 30 min UV exposure resulted in 75% reduction of rETR{sub max} with only a 43% recovery as compared with the initial after 24 h recovery. After a 60 min UV-B exposure, there were no Chl a fluorescence signals, and hence no F{sub v}/F{sub m} or rETR{sub max}. A UV dose-dependent increase in DCFH-DA fluorescence was found in E. agilis cells, reflecting an increase in ROS production. After exposures to UV-B for between 15 and 60 min, the percentages of motile cells in the population decreased to 76, 39 and 15

  5. Proximal hamstring reconstruction using semitendinosus and gracilis autograft: a novel technique.

    Science.gov (United States)

    Muellner, Thomas; Kumar, Sandeep; Singla, Amit

    2017-01-01

    The complete proximal hamstring avulsion is relatively uncommon injury and predominantly occurs in young athletes but causes significant functional impairment. In chronic cases, the muscle mass is so much retracted that primary repair is not possible. A surgical technique for reconstruction of chronic proximal hamstring avulsion using contralateral semitendinosus and gracilis autograft is described in this case report. V.

  6. Chemical Composition Variability of Essential Oils of Daucus gracilis Steinh. from Algeria.

    Science.gov (United States)

    Benyelles, Batoul; Allali, Hocine; Dib, Mohamed El Amine; Djabou, Nassim; Paolini, Julien; Costa, Jean

    2017-06-01

    The chemical compositions of 20 Algerian Daucus gracilis essential oils were investigated using GC-FID, GC/MS, and NMR analyses. Altogether, 47 compounds were identified, accounting for 90 - 99% of the total oil compositions. The main components were linalool (18; 12.5 - 22.6%), 2-methylbutyl 2-methylbutyrate (20; 9.2 - 20.2%), 2-methylbutyl isobutyrate (10; 4.2 - 12.2%), ammimajane (47; 2.6 - 37.1%), (E)-β-ocimene (15; 0.2 - 12.8%) and 3-methylbutyl isovalerate (19; 3.3 - 9.6%). The chemical composition of the essential oils obtained from separate organs was also studied. GC and GC/MS analysis of D. gracilis leaves and flowers allowed identifying 47 compounds, amounting to 92.3% and 94.1% of total oil composition, respectively. GC and GC/MS analysis of D. gracilis leaf and flower oils allowed identifying linalool (22.7%), 2-methylbutyl 2-methylbutyrate (18.9%), 2-methylbutyl isovalerate (13.6%), ammimajane (10.4%), 3-methylbutyl isovalerate (10.3%), (E)-β-ocimene (8.4%) and isopentyl 2-methylbutyrate (8.1%) as main components. The chemical variability of the Algerian oil samples was studied using statistical analysis, which allowed the discrimination of three main Groups. A direct correlation between the altitudes, nature of soils and the chemical compositions of the D. gracilis essential oils was evidenced. © 2017 Wiley-VHCA AG, Zurich, Switzerland.

  7. Consequences of acclimation to Microcystis on the selective feeding behavior of the calanoid copepod Eudiaptomus gracilis

    NARCIS (Netherlands)

    Ger, K.A.; Panosso, R.; Lürling, M.

    2011-01-01

    We tested the hypothesis that calanoid copepods would adapt to extended periods of Microcystis exposure by increasing selective feeding on alternative food. Copepod (Eudiaptomus gracilis) clearance rates were compared before and after a 5-d acclimation to Microcystis aeruginosa using paired food

  8. Gracilioethers A-C, Antimalarial Metabolites from the Marine Sponge Agelas gracilis

    NARCIS (Netherlands)

    Ueoka, R.; Nakao, Y.; Kawatsu, S.; Yaegashi, J.; Matsumoto, Y.; Matsunaga, S.; Furihata, K; van Soest, R.W.M.; Fusetani, N.

    2009-01-01

    Three new antiprotozoan compounds, gracilioethers A−C (1−3), have been isolated from the marine sponge Agelas gracilis. Their structures were elucidated on the basis of spectroscopic and chemical methods. Gracilioethers A−C showed antimalarial activity against Plasmodium falciparum with IC50 values

  9. Antioxidant, anti-inflammatory and antiproliferative activities of Kalanchoe gracilis (L.) DC stem.

    Science.gov (United States)

    Lai, Zhen-Rung; Ho, Yu-Ling; Huang, Shun-Chieh; Huang, Tai-Hung; Lai, Shang-Chih; Tsai, Jen-Chieh; Wang, Ching-Ying; Huang, Guan-Jhong; Chang, Yuan-Shiun

    2011-01-01

    Oxidative stress and inflammation are related to several chronic diseases including cancer and atherosclerosis. Kalanchoe gracilis (L.) DC is a special folk medicinal plant in Taiwan. The aim of this study was to evaluate the antioxidant, anti-inflammatory and antiproliferative activities of the methanolic extract and fractions of the stem of K. gracilis. TEAC, total phenolic compound content, total flavonoid content, DPPH radical scavenging activity, reducing power, inhibition of NO production in LPS-induced RAW264.7 cells, and inhibition of cancer cell proliferation were analyzed. Among all fractions, the chloroform fraction showed the highest TEAC and DPPH radical scavenging activities. The chloroform fraction also had the highest content of polyphenols and flavonoids. Chloroform fractions also decreased LPS-induced NO production and expressions of iNOS and COX-2 in RAW264.7 cells. The antiproliferative activities of the methanolic extract and fractions were studied in vitro using HepG2 cells, and the results were consistent with their antioxidant capacities. Chloroform fractions had the highest antiproliferative activity with an IC(50) of 136.85 ± 2.32 μg/ml. Eupafolin also had good pharmacological activity in the antioxidant, anti-inflammation and antiproliferative. Eupafolin might be an important bioactive compound in the stem of K. gracilis. The above experimental data indicated that the stem of K. gracilis is a potent antioxidant medicinal plant, and such efficacy may be mainly attributed to its polyphenolic compounds.

  10. 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

  11. 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.

  12. 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.

  13. 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.

  14. Chemical analysis, antimicrobial and anti-oxidative properties of Daucus gracilis essential oil and its mechanism of action

    Directory of Open Access Journals (Sweden)

    Meriem El Kolli

    2016-01-01

    Conclusions: D. gracilis EO showed potent antimicrobial and anti-oxidative activities and had acted on the cytoplasm membrane. These activities could be exploited in the food industry for food preservation.

  15. 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...

  16. Comparison between direct transesterification of microalgae and hydrochar

    Directory of Open Access Journals (Sweden)

    Vo Thanh Phuoc

    2017-07-01

    Full Text Available Hydrothermal carbonization (HTC of microalgae is one of processes that can effectively remove moisture from microalgae. In addition, the hydrochar retains most of fatty acids from microalgae feedstock, and the content of fatty acids in hydrochar is doubled. This research concentrates on the comparison between direct transesterification of microalgae and hydrochar. The result shows that the biodiesel yields of hydrochar were higher than those of microalgae at the same reaction conditions due to the higher extraction rate of fatty acids from hydrochar. Finally, the amount of methanol and catalyst which is required for a given amount of microalgae can be reduced to a half through the direct transesterification of hydrochar.

  17. Marine Microalgae with Anti-Cancer Properties.

    Science.gov (United States)

    Martínez Andrade, Kevin A; Lauritano, Chiara; Romano, Giovanna; Ianora, Adrianna

    2018-05-15

    Cancer is the leading cause of death globally and finding new therapeutic agents for cancer treatment remains a major challenge in the pursuit for a cure. This paper presents an overview on microalgae with anti-cancer activities. Microalgae are eukaryotic unicellular plants that contribute up to 40% of global primary productivity. They are excellent sources of pigments, lipids, carotenoids, omega-3 fatty acids, polysaccharides, vitamins and other fine chemicals, and there is an increasing demand for their use as nutraceuticals and food supplements. Some microalgae are also reported as having anti-cancer activity. In this review, we report the microalgal species that have shown anti-cancer properties, the cancer cell lines affected by algae and the concentrations of compounds/extracts tested to induce arrest of cell growth. We also report the mediums used for growing microalgae that showed anti-cancer activity and compare the bioactivity of these microalgae with marine anticancer drugs already on the market and in phase III clinical trials. Finally, we discuss why some microalgae can be promising sources of anti-cancer compounds for future development.

  18. 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

  19. Microalgae growth on the aqueous phase from Hydrothermal Liquefaction of the same microalgae

    NARCIS (Netherlands)

    Garcia Alba, Laura; Torri, Cristian; Fabbri, Daniele; Kersten, Sascha R.A.; Brilman, Derk Willem Frederik

    2013-01-01

    Cultivation of Desmodesmus sp. microalgae in the recycled aqueous phase (AP) recovered after Hydrothermal Liquefaction (HTL) of the same microalgae was studied to evaluate the potential of nutrients recycling. AP dilution ratio was systematically varied, using either water or water enriched with

  20. Adynamic Graciloplasty With a Pedicled Gracilis Muscle Flap Wrapped Around Bulbar Urethra for Treatment of Male Acquired Urinary Incontinence.

    Science.gov (United States)

    Guo, Hailin; Sa, Yinglong; Xu, Yuemin; Wang, Lin; Fei, Xiaofang

    2016-05-01

    To evaluate the efficacy of adynamic gracilis urethral myoplasty with a pedicled gracilis muscle flap wrapped around bulbar urethra for treatment of male acquired urinary incontinence. Twenty-four patients with acquired urinary incontinence (8 after radical prostatectomy, 7 after transurethral resection of the prostate, and 9 after posterior urethroplasty) were included in our study. Eighteen of these patients (75.0%) had mild to moderate urinary incontinence, and 6 (25.0%) had severe urinary incontinence. All patients received adynamic gracilis urethral myoplasty with a pedicled gracilis muscle flap wrapped around bulbar urethra and had a close follow-up. The mean postoperative maximum urethral pressure after the gracilis muscle wrapped around bulbar urethra was significantly higher than that of the preoperative measurements (P urethra can raise the urethral pressure. Adynamic graciloplasty with a pedicled gracilis muscle flap wrapped around bulbar urethra is a safe and effective surgical option in the treatment of male patients with mild to moderate incontinence, but is not suitable for severe incontinence. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Can the gracilis be used to replace the anterior cruciate ligament in the knee? A cadaver study.

    Science.gov (United States)

    Cavaignac, Etienne; Pailhé, Regis; Murgier, Jérôme; Reina, Nicolas; Lauwers, Frederic; Chiron, Philippe

    2014-12-01

    The purpose of this study was to evaluate whether a four-strand gracilis-only graft can be used in anterior cruciate ligament (ACL) reconstruction. Cadaver study. This study involved 16 cadaver knees. The length and diameter of the native ACL were measured in each one. The same measurements were performed on a four-strand graft of the gracilis only, the semitendinosus only and both tendons. Student's t-test was used to compare the various conditions. The average diameter of the G4 construct was 0.07 mm greater (1%) than the native ACL (p=0.044). The average cross-sectional area of the G4 construct was 1.2 mm(2) greater (3.9%) than the native ACL (p=0.049). The G4 was on average 38.9 mm longer than the intra-articular portion of the ACL (p<0.001). A four-strand gracilis construct meets the anatomical specifications for use as an ACL reconstruction graft. By using the gracilis only, the morbidity associated with harvesting the gracilis and semitendinosus tendons should be reduced. Further studies must be performed to compare the biomechanical properties of this graft with other graft types and also to evaluate how this four-strand gracilis graft behaves in a clinical setting. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Desenvolvimento marsupial e pós-marsupial de Janaira Gracilis (Crustacea, Isopoda, Asellota Marsupial and postmarsupial development of Janaira gracilis

    Directory of Open Access Journals (Sweden)

    Ana Maria Setubal Pires

    1977-01-01

    Full Text Available No presente estudo são descritos os estádios de desenvolvimento de Janaira gracilis e discutidos vários aspectos de seu crescimento. Coletou-se o material mensalmente, de janeiro de 1972 a janeiro de 1973, junto ao trapiche da Base Norte do Instituto Oceanográfico da Universidade de São Paulo, Ubatuba, Estado de Sao Paulo. Janaira gracilis apresenta 4 estádios de desenvolvimento marsupial, 9 de desenvolvimento pós-marsupial para as fêmeas, e 10 para os machos. Os estádios pós-marsupiais podem ser bem determinados através do número de artículos do flagelo da antena 1, pereópodo I e VII, pleópodos 1 e 2 masculino e desenvolvimento de oostégitos na fêmea. As transformações decorrentes do desenvolvimento pós-marsupial são mais marcantes nos machos, pois as fêmeas conservam uma morfologia juvenil e uniforme durante toda a sua vida. O crescimento médio dos machos suplanta o das fêmeas a partir do estádio 7. Nestas, a diminuição de crescimento observada deve-se, provavelmente, à utilização crescente de energia disponível, para fins reprodutivos. Os machos alcançam a maturidade sexual precocemente às fêmeas.The development and growth of Janaira gracilis are described and discussed. The sampling was carried out once a month from January 1972 to January 1973 at the pier of Base Norte, Instituto Oceanográfico USP, Ubatuba, State of São Paulo. Four distinct marsupial stages were disclosed in the development of Janaira gracilis as well as 9 distinct postmarsupial stages for the females and 10 for the males. Every postmarsupial instar can be distinguished by morphological features, such as first antennae articles, first and seventh pereopod, first and second pair of pleopods and the oostegites. During the course of development females undergo less morphological changes than males. Considering the final stages, in average males are larger than females. It is suggested that the decrease in growth of females may be related to

  3. Antioxidative properties of some phototropic microalgae grown in waste water

    DEFF Research Database (Denmark)

    Safafar, Hamed; Jacobsen, Charlotte; Møller, Peter

    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...

  4. With a flick of the lid: a novel trapping mechanism in Nepenthes gracilis pitcher plants.

    Directory of Open Access Journals (Sweden)

    Ulrike Bauer

    Full Text Available Carnivorous pitcher plants capture prey with modified leaves (pitchers, using diverse mechanisms such as 'insect aquaplaning' on the wet pitcher rim, slippery wax crystals on the inner pitcher wall, and viscoelastic retentive fluids. Here we describe a new trapping mechanism for Nepenthes gracilis which has evolved a unique, semi-slippery wax crystal surface on the underside of the pitcher lid and utilises the impact of rain drops to 'flick' insects into the trap. Depending on the experimental conditions (simulated 'rain', wet after 'rain', or dry, insects were captured mainly by the lid, the peristome, or the inner pitcher wall, respectively. The application of an anti-slip coating to the lower lid surface reduced prey capture in the field. Compared to sympatric N. rafflesiana, N. gracilis pitchers secreted more nectar under the lid and less on the peristome, thereby directing prey mainly towards the lid. The direct contribution to prey capture represents a novel function of the pitcher lid.

  5. Surgical repair of rectovaginal fistula using gracilis muscular flap. A case report

    Energy Technology Data Exchange (ETDEWEB)

    Inoue, Yasuhiro; Ooi, Masataka; Takeuchi, Kenji; Honzumi, Makoto [Nabari City Hospital, Mie (Japan); Fukunishi, Shigeji

    1999-07-01

    A 78 year-old female suffered from vaginal discharge of flatus and stool for 20 years after the radiation therapy for cervical cancer. Digital and endoscopic examination of the rectum and the vagina disclosed a large, short rectovaginal fistula at the level of the cervix. Since laparotomy and low anterior resection of the rectum were impossible, a perineal approach was adopted. After perineal skin incision, the fistula was resected and the defects of the rectum and the vagina were closed. Gracilis muscular flap was anchored between the two closures. Though the closure of the rectal side was torn, her postoperative course was uneventful. Endoscopic examination 24 days after the operation confirmed healing of the dehiscence. The results verified the usefulness of the perineal approach using the gracilis muscular flap as an alternative method to low anterior resection for troublesome radiation induced rectovaginal fistula. (author)

  6. Surgical repair of rectovaginal fistula using gracilis muscular flap. A case report

    International Nuclear Information System (INIS)

    Inoue, Yasuhiro; Ooi, Masataka; Takeuchi, Kenji; Honzumi, Makoto; Fukunishi, Shigeji

    1999-01-01

    A 78 year-old female suffered from vaginal discharge of flatus and stool for 20 years after the radiation therapy for cervical cancer. Digital and endoscopic examination of the rectum and the vagina disclosed a large, short rectovaginal fistula at the level of the cervix. Since laparotomy and low anterior resection of the rectum were impossible, a perineal approach was adopted. After perineal skin incision, the fistula was resected and the defects of the rectum and the vagina were closed. Gracilis muscular flap was anchored between the two closures. Though the closure of the rectal side was torn, her postoperative course was uneventful. Endoscopic examination 24 days after the operation confirmed healing of the dehiscence. The results verified the usefulness of the perineal approach using the gracilis muscular flap as an alternative method to low anterior resection for troublesome radiation induced rectovaginal fistula. (author)

  7. Spermiogenesis and spermatozoon of the tapeworm Parabothriocephalus gracilis (Bothriocephalidea): Ultrastructural and cytochemical studies

    Czech Academy of Sciences Publication Activity Database

    Šípková, Lenka; Levron, Céline; Freeman, M.; Scholz, Tomáš

    2010-01-01

    Roč. 55, č. 1 (2010), s. 58-65 ISSN 1230-2821 R&D Projects: GA ČR GP524/07/P039; GA ČR GA524/08/0885; GA MŠk LC522 Institutional research plan: CEZ:AV0Z60220518 Keywords : Eucestoda * Bothriocephalidea * Parabothriocephalus gracilis * spermiogenesis * spermatozoon * ultrastructure Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 1.144, year: 2010

  8. Kalanchosides A-C, new cytotoxic bufadienolides from the aerial parts of Kalanchoe gracilis.

    Science.gov (United States)

    Wu, Pei-Lin; Hsu, Yu-Lin; Wu, Tian-Shung; Bastow, K F; Lee, Kuo-Hsiung

    2006-11-09

    [Structure: see text] Three new compounds, kalanchosides A-C (1-3), as well as five known compounds, were isolated from the aerial parts of Kalanchoe gracilis. The compound structures were determined by spectroscopic methods. All eight isolated compounds showed significant cytotoxic activity against a panel of human tumor cell lines, with potency reaching the nanomolar range. However, only bryophyllin B (8) inhibited HIV replication in H9 lymphocyte cells.

  9. A rapid phenol toxicity test based on photosynthesis and movement of the freshwater flagellate, Euglena agilis Carter

    International Nuclear Information System (INIS)

    Kottuparambil, Sreejith; Kim, Youn-Jung; Choi, Hoon; Kim, Mi-Sung; Park, Areum; Park, Jihae; Shin, Woongghi; Han, Taejun

    2014-01-01

    Highlights: • Rapid phenol toxicity tests (1 h) were developed based on Chl a fluorescence and the movement parameters of Euglena agilis. • Phenol significantly reduced F v /F m of PS II and rETRmax with EC50 values of 8.94 and 4.67 mM, respectively. • Among the movement parameters tested, velocity was the most sensitive biomarker with an EC50 of 3.17 mM. • The EC50 values for F v /F m , motility, and velocity appear to overlap the environmental permissible levels of phenol. - Abstract: Phenol, a monosubstituted aromatic hydrocarbon with various commercial uses, is a major organic constituent in industrial wastewaters. The ecotoxic action of phenol for aquatic environment is well known. In this study, rapid phenol toxicity tests (1 h) were developed based on chlorophyll a (Chl a) fluorescence and the movement parameters of the freshwater flagellate, Euglena agilis Carter. Phenol significantly reduced the maximum quantum yield (F v /F m ) of photosystem II (PS II) and the maximum photosynthetic electron transport rate (rETR max ) with median effective concentration (EC 50 ) values of 8.94 and 4.67 mM, respectively. Phenol reduced the motility and triggered change in the swimming velocity of the test organism. Among the parameters tested, velocity was the most sensitive biomarker with an EC 50 of 3.17 mM. The EC 50 values for F v /F m , motility, and velocity appear to overlap the permitted levels of phenol. In conclusion, the photosynthesis and movement of E. agilis can be fast and sensitive risk assessment parameters for the evaluation of phenol toxicity in municipal and industrial effluents

  10. A rapid phenol toxicity test based on photosynthesis and movement of the freshwater flagellate, Euglena agilis Carter

    Energy Technology Data Exchange (ETDEWEB)

    Kottuparambil, Sreejith [Institute of Green Environmental Research Center, Incheon National University, Incheon 406 840 (Korea, Republic of); Kim, Youn-Jung [Institute of Green Environmental Research Center, Incheon National University, Incheon 406 840 (Korea, Republic of); Department of Marine Science, Incheon National University, Incheon 406 840 (Korea, Republic of); Green-Pioneer (Ltd.), Incheon National University, Incheon 406 840 (Korea, Republic of); Choi, Hoon; Kim, Mi-Sung; Park, Areum; Park, Jihae [Institute of Green Environmental Research Center, Incheon National University, Incheon 406 840 (Korea, Republic of); Shin, Woongghi [Department of Biology, Chungnam University, Daejeon 306 764 (Korea, Republic of); Han, Taejun, E-mail: hanalgae@hanmail.net [Institute of Green Environmental Research Center, Incheon National University, Incheon 406 840 (Korea, Republic of); Department of Marine Science, Incheon National University, Incheon 406 840 (Korea, Republic of); Green-Pioneer (Ltd.), Incheon National University, Incheon 406 840 (Korea, Republic of)

    2014-10-15

    Highlights: • Rapid phenol toxicity tests (1 h) were developed based on Chl a fluorescence and the movement parameters of Euglena agilis. • Phenol significantly reduced F{sub v}/F{sub m} of PS II and rETRmax with EC50 values of 8.94 and 4.67 mM, respectively. • Among the movement parameters tested, velocity was the most sensitive biomarker with an EC50 of 3.17 mM. • The EC50 values for F{sub v}/F{sub m}, motility, and velocity appear to overlap the environmental permissible levels of phenol. - Abstract: Phenol, a monosubstituted aromatic hydrocarbon with various commercial uses, is a major organic constituent in industrial wastewaters. The ecotoxic action of phenol for aquatic environment is well known. In this study, rapid phenol toxicity tests (1 h) were developed based on chlorophyll a (Chl a) fluorescence and the movement parameters of the freshwater flagellate, Euglena agilis Carter. Phenol significantly reduced the maximum quantum yield (F{sub v}/F{sub m}) of photosystem II (PS II) and the maximum photosynthetic electron transport rate (rETR{sub max}) with median effective concentration (EC{sub 50}) values of 8.94 and 4.67 mM, respectively. Phenol reduced the motility and triggered change in the swimming velocity of the test organism. Among the parameters tested, velocity was the most sensitive biomarker with an EC{sub 50} of 3.17 mM. The EC{sub 50} values for F{sub v}/F{sub m}, motility, and velocity appear to overlap the permitted levels of phenol. In conclusion, the photosynthesis and movement of E. agilis can be fast and sensitive risk assessment parameters for the evaluation of phenol toxicity in municipal and industrial effluents.

  11. Effects of TiO2 nanoparticles and sunscreens on coastal marine microalgae: Ultraviolet radiation is key variable for toxicity assessment.

    Science.gov (United States)

    Sendra, M; Sánchez-Quiles, D; Blasco, J; Moreno-Garrido, I; Lubián, L M; Pérez-García, S; Tovar-Sánchez, A

    2017-01-01

    Given the large numbers of sunbathers on beaches, sunscreen compounds are being released into the coastal aquatic environment in significant amounts. Until now the effect of these potential pollutants on microbiota has been not well-known. Phytoplankton is a key component of the microbiota community. It forms the basis of the aquatic trophic networks, and any change in the natural population of phytoplankton can affect the structure of aquatic biota. This paper describes an experiment performed outdoors (in natural sunlight conditions including ultraviolet radiation (UVR) and with UVR blocked) on mixed microalgae populations (four species from different key marine taxonomic groups, Nannochloropsis gaditana, Chaetoceros gracilis, Pleurochrysis roscoffensis and Amphidinium carterae), for three days, exposed to a range of concentrations of three commercial sunscreens (with variable TiO 2 concentrations: highest concentration for sunscreen C, followed by sunscreen A; and sunscreen B did not contain TiO 2 in its composition). With regard to UVR effect, in the absence of sunscreens, the most sensitive species is the centric diatom, Chaetoceros gracilis, and the least is Nannochloropsis gaditana; this last species presented the same behavior in the absence of UVR and with high sunscreen concentrations. The toxicity gradient obtained for sunscreens and nanoparticles under UVR is: TiO 2 NPs>Sunscreen C>Sunscreen A>Sunscreen B. The differential sensitivity of microalgae to sunscreens and TiO 2 NPs can produce a change in the dynamics of phytoplankton populations and provoke undesirable ecological effects (such as giving dinoflagellates more prominence). The effects of UVR, commonly neglected in bioassays, could alter the results in important ways and should be considered when performing environmentally-relevant bioassays. The toxicity mediated by hydrogen peroxide production associated with the concentration of TiO 2 NPs cannot be considered the only factor responsible for

  12. Treatment of ischial pressure sores using a modified gracilis myofasciocutaneous flap.

    Science.gov (United States)

    Lin, Haodong; Hou, Chunlin; Chen, Aimin; Xu, Zhen

    2010-04-01

    Despite the availability of a variety of flap reconstruction options, ischial pressure sores continue to be the most difficult pressure sores to treat. This article describes a successful surgical procedure for the coverage of ischial ulcers using a modified gracilis myofasciocutaneous flap. From August 2000 to April 2004, 12 patients with ischial sores were enrolled in the study. All patients underwent early aggressive surgical debridement followed by surgical reconstruction with a modified gracilis myofasciocutaneous flap. The follow-up period ranged from 13 to 86 months, with a mean of 44 months. Overall, 91.7% of the flaps (11 of 12) survived primarily. Partial flap necrosis occurred in one patient. Primary wound healing occurred without complications at both the donor and recipient sites in all cases. In one patient, grade II ischial pressure sores recurred 13 months after the operation. There was no recurrence in other 11 patients. A modified gracilis myofasciocutaneous flap provides a good cover for ischial pressure sores. Because it is easy to use and has favorable results, it can be used in the primary treatment for large and deep ischial pressure sores. Copyright Thieme Medical Publishers.

  13. Free gracilis muscle transfer for smile reanimation after treatment for advanced parotid malignancy.

    Science.gov (United States)

    Faris, Callum; Heiser, Alyssa; Hadlock, Tessa; Jowett, Nate

    2018-03-01

    The purpose of this study was to characterize the outcomes of free gracilis muscle transfer for delayed smile reanimation after radical parotidectomy. A retrospective chart review of patients who underwent free gracilis muscle transfer for smile reanimation after radical parotidectomy between 2003 and 2016 was performed. Patient-reported quality of life (Facial Clinimetric Evaluation Scale [FaCE]), physician-reported facial function ("eFACE" facial grading scale), and oral commissure excursion were compared preoperatively and postoperatively. Twelve patients were identified with prior surgery and adjuvant therapy (radiotherapy in 6 cases and chemoradiotherapy in 6 cases). Significant postoperative improvements were demonstrated for ipsilateral commissure excursion with smile (preoperatively: -2.2 mm [SD 2.3 mm] vs postoperatively: 7.9 mm [SD 2.5 mm]; P = .002), with meaningful smile achieved in 11 of 12 cases (91.7%). The average duration of facial paralysis before intervention was 72 months (range 12-204 months). Free gracilis muscle transfer is an option for dynamic smile reanimation in select patients who have undergone treatment for advanced parotid malignancy. © 2017 Wiley Periodicals, Inc.

  14. 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

  15. Harvesting microalgae by bio-flocculation and autoflocculation

    NARCIS (Netherlands)

    Salim, S.

    2013-01-01

    Harvesting in commercial microalgae production plants is generally done by centrifugation, but this requires upto about 50% of the total energy gained from the microalgae. The energy needed for harvesting can be reduced considerably by pre-concentration of the microalgae prior to further dewatering.

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

    African Journals Online (AJOL)

    Therefore, the microalga was introduced to be cultivated in the biogas wastewater, which could not only bioremediate the wastewater, but also produce plenty of the microalga biomass that could be used for the exploitation of fertilizers, feed additives and biofuels. This study showed that the microalga, C. pyrenoidosa could ...

  17. Factors affecting growth of the spiny lobsters Panulirus gracilis and Panulirus inflatus (Decapoda: Palinuridae in Guerrero, México

    Directory of Open Access Journals (Sweden)

    Patricia Briones-Fourzán

    2003-03-01

    Full Text Available The effects of sex, injuries, season and site on the growth of the spiny lobsters Panulirus gracilis, and P. inflatus, were studied through mark-recapture techniques in two sites with different ecological characteristics on the coast of Guerrero, México. Panulirus gracilis occurred in both sites, whereas P. inflatus occurred only in one site. All recaptured individuals were adults. Both species had similar intermolt periods, but P. gracilis had significantly higher growth rates (mm carapace length week -1 than P. inflatus as a result of a larger molt increment. Growth rates of males were higher than those of females in both species owing to larger molt increments and shorter intermolt periods in males. Injuries had no effect on growth rates in either species. Individuals of P. gracilis grew faster in site 1 than in site 2. Therefore, the effect of season on growth of P. gracilis was analyzed separately in each site. In site 2, growth rates of P. gracilis were similar in summer and in winter, whereas insite 1 both species had higher growth rates in winter than in summer. This could be due to spatial differences in processes related to changes in population density and food resources, which were documented in previous works. The overall results show that P. gracilis grows faster than P. inflatus, and that growth rates of both species are highly variable and are affected by environmental factors such as site and season, which should be taken into account when attempting to produce population growth curves for each species.Se analizaron, por medio de marcado-recaptura, los efectos del sexo, heridas, estación del año y localidad sobre el crecimiento de las langostas espinosas Panulirus gracilis Streets, 1871, y Panulirus inflatus (Bouvier, 1895 en dos localidades con diferentes características ecológicas en la costa de Guerrero, México. Panulirus gracilis se presentó en ambas localidades, mientras que P. inflatus sólo se encontró en una de

  18. 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

  19. Posteromedial knee friction syndrome: an entity with medial knee pain and edema between the femoral condyle, sartorius and gracilis.

    Science.gov (United States)

    Simeone, F Joseph; Huang, Ambrose J; Chang, Connie Y; Smith, Maximilian; Gill, Thomas J; Bredella, Miriam A; Torriani, Martin

    2015-04-01

    To describe MRI features of an entity consisting of medial knee pain and edema between the posteromedial femoral condyle (PMFC), sartorius and/or gracilis tendons and determine whether reduced tendon-bone distances may account for these findings. We retrospectively identified MRI cases of edema between the PMFC, sartorius and/or gracilis tendons (25 subjects, 26 knees). Two musculoskeletal radiologists independently graded edema and measured the sartorius- and gracilis-PMFC distances and knee flexion angle. Age- and gender-matched subjects with normal knee MRIs (27 subjects, 27 knees) served as controls for measurements. Statistical analyses compared abnormal to control subjects. Sartorius-PMFC and gracilis-PMFC spaces were narrower in abnormal compared to control subjects (1.6 ± 1.0 vs. 2.1 ± 1.2 mm, P = 0.04; 2.3 ± 2.0 vs. 4.6 ± 3.0 mm, P = 0.002, respectively). The knee flexion angle was similar between groups (P > 0.05). In subjects with clinical information, medial knee pain was the main complaint in 58 % (15/26) of abnormal subjects, with 42 % (11/26) having clinical suspicion of medial meniscal tear. Edema between the PMFC, sartorius and/or gracilis was mild in 54 % (14/26), moderate in 35 % (9/26) and severe in 12 % (3/26), and it was most frequent deep to both the sartorius and gracilis (50 %, 13/26). Edema between the PMFC, sartorius and/or gracilis tendons identified on knee MRI may be associated with medial knee pain and may represent a friction syndrome.

  20. Posteromedial knee friction syndrome: an entity with medial knee pain and edema between the femoral condyle, sartorius and gracilis

    Energy Technology Data Exchange (ETDEWEB)

    Simeone, F.J.; Huang, Ambrose J.; Chang, Connie Y.; Smith, Maximilian; Bredella, Miriam A.; Torriani, Martin [Massachusetts General Hospital and Harvard Medical School, Division of Musculoskeletal Imaging and Intervention, Department of Radiology, Boston, MA (United States); Gill, Thomas J. [Boston Sports Medicine and Research Institute, Boston, MA (United States)

    2014-12-20

    To describe MRI features of an entity consisting of medial knee pain and edema between the posteromedial femoral condyle (PMFC), sartorius and/or gracilis tendons and determine whether reduced tendon-bone distances may account for these findings. We retrospectively identified MRI cases of edema between the PMFC, sartorius and/or gracilis tendons (25 subjects, 26 knees). Two musculoskeletal radiologists independently graded edema and measured the sartorius- and gracilis-PMFC distances and knee flexion angle. Age- and gender-matched subjects with normal knee MRIs (27 subjects, 27 knees) served as controls for measurements. Statistical analyses compared abnormal to control subjects. Sartorius-PMFC and gracilis-PMFC spaces were narrower in abnormal compared to control subjects (1.6 ± 1.0 vs. 2.1 ± 1.2 mm, P = 0.04; 2.3 ± 2.0 vs. 4.6 ± 3.0 mm, P = 0.002, respectively). The knee flexion angle was similar between groups (P > 0.05). In subjects with clinical information, medial knee pain was the main complaint in 58 % (15/26) of abnormal subjects, with 42 % (11/26) having clinical suspicion of medial meniscal tear. Edema between the PMFC, sartorius and/or gracilis was mild in 54 % (14/26), moderate in 35 % (9/26) and severe in 12 % (3/26), and it was most frequent deep to both the sartorius and gracilis (50 %, 13/26). Edema between the PMFC, sartorius and/or gracilis tendons identified on knee MRI may be associated with medial knee pain and may represent a friction syndrome. (orig.)

  1. Posteromedial knee friction syndrome: an entity with medial knee pain and edema between the femoral condyle, sartorius and gracilis

    International Nuclear Information System (INIS)

    Simeone, F.J.; Huang, Ambrose J.; Chang, Connie Y.; Smith, Maximilian; Bredella, Miriam A.; Torriani, Martin; Gill, Thomas J.

    2015-01-01

    To describe MRI features of an entity consisting of medial knee pain and edema between the posteromedial femoral condyle (PMFC), sartorius and/or gracilis tendons and determine whether reduced tendon-bone distances may account for these findings. We retrospectively identified MRI cases of edema between the PMFC, sartorius and/or gracilis tendons (25 subjects, 26 knees). Two musculoskeletal radiologists independently graded edema and measured the sartorius- and gracilis-PMFC distances and knee flexion angle. Age- and gender-matched subjects with normal knee MRIs (27 subjects, 27 knees) served as controls for measurements. Statistical analyses compared abnormal to control subjects. Sartorius-PMFC and gracilis-PMFC spaces were narrower in abnormal compared to control subjects (1.6 ± 1.0 vs. 2.1 ± 1.2 mm, P = 0.04; 2.3 ± 2.0 vs. 4.6 ± 3.0 mm, P = 0.002, respectively). The knee flexion angle was similar between groups (P > 0.05). In subjects with clinical information, medial knee pain was the main complaint in 58 % (15/26) of abnormal subjects, with 42 % (11/26) having clinical suspicion of medial meniscal tear. Edema between the PMFC, sartorius and/or gracilis was mild in 54 % (14/26), moderate in 35 % (9/26) and severe in 12 % (3/26), and it was most frequent deep to both the sartorius and gracilis (50 %, 13/26). Edema between the PMFC, sartorius and/or gracilis tendons identified on knee MRI may be associated with medial knee pain and may represent a friction syndrome. (orig.)

  2. 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.

  3. 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.

  4. 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.

  5. 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...

  6. Evaluation of the analgesic and anti-inflammatory effects of the essential oil of Lippia gracilis leaves.

    Science.gov (United States)

    Mendes, S S; Bomfim, R R; Jesus, H C R; Alves, P B; Blank, A F; Estevam, C S; Antoniolli, A R; Thomazzi, S M

    2010-06-16

    The aim of the present study is to investigate the antinociceptive, anti-inflammatory, and antioxidant activities of essential oil (EO) of Lippia gracilis Schauer (Verbenaceae) leaves to support the medicinal uses claimed by folklore practitioners in the caatinga region (semi-arid) of Northeastern Brazil. The chemical composition and antinociceptive and anti-inflammatory activities of the EO of Lippia gracilis leaves (50-200 mg/kg) were investigated. Antinociceptive activity of the EO was evaluated by writhing test. Anti-inflammatory activity of the EO was evaluated using paw oedema and peritonitis methods. Oral treatment with the EO of Lippia gracilis leaves elicited inhibitory activity on acetic acid effect at 50, 100, and 200 mg/kg (30.33+/-2.36, 25.20+/-1.48, and 21.00+/-1.54 abdominal writhes, respectively, Pleaves at 200 mg/kg (0.72+/-0.06 mL h, Pleaves at 50, 100, and 200 mg/kg (13.81+/-0.61, 11.77+/-0.91, and 10.30+/-0.60 leukocytes x 10(6)/mL, respectively, Pessential oil allowed the identification of Lippia gracilis as a thymol-p-cymene chemotype (32.68% and 17.82%, respectively). The EO of Lippia gracilis leaves shows antinociceptive and anti-inflammatory activities. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

  7. 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.

  8. Estabelecimento de protocolo para micropropagação de Lippia gracilis Schauer Establishment of protocol for Lippia gracilis Schauer micropropagation

    Directory of Open Access Journals (Sweden)

    M.J.M Marinho

    2011-01-01

    Full Text Available A espécie Lippia gracilis SCHAUER (Verbenaceae é nativa do Nordeste brasileiro e se destaca pela capacidade de acumular nos tricomas glandulares óleos essenciais com atividade antimicrobiana. Tendo em vista que não constam trabalhos na literatura sobre o estabelecimento in vitro dessa espécie, este trabalho teve como objetivo estabelecer protocolo para micropropagação de L. gracilis. Para tanto, ramos contendo folhas foram coletados de plantas matrizes no habitat natural para a confecção de estacas. Em laboratório, os explantes provenientes do processo de estaquia foram assepticamente tratados e inoculados em meio MS, acrescido de fitorreguladores, com o intuito de se estabelecer a melhor dose para o desenvolvimento dos explantes. Em decorrência de altos níveis de contaminação, avaliou-se o efeito da cefalexina. No entanto, apesar do antibiótico ter apresentado diminuição na contaminação bacteriana, a porcentagem de oxidação foi elevada. Portanto, testou-se o carvão ativado, ácido ascórbico, ácido cítrico e metade dos sais de MS quanto a eficiência no controle da oxidação. Concluiu-se que, o antibiótico na concentração utilizada provocou a oxidação dos explantes e os fitorreguladores, bem como os métodos antioxidantes testados, não apresentaram resultados consistentes para o melhor desenvolvimento dos explantes e controle da oxidação, respectivamente.The species Lippia gracilis Schauer (Verbenaceae is native to Northeastern Brazil and has been important for its ability to accumulate essential oils with antimicrobial activity in the glandular trichomes. Since there are no reports in the literature on the micropropagation of this species, the present work aimed to establish a protocol for L. gracilis micropropagation. Thus, branches containing leaves were collected from plant matrices in their natural habitat to prepare cuttings. In the laboratory, explants from cutting were aseptically treated and inoculated

  9. Observations on the symbiosis between Colus gracilis (Da Costa, 1778) (Mollusca: Gastropoda) and Hormathia digitata (O.F. Müller, 1776) (Cnidaria: Actiniaria)

    NARCIS (Netherlands)

    Ates, R.M.L.

    1998-01-01

    Aquarium observations of the behaviour of the actinian Hormathia digitata when mounting live specimens of the gastropod Colus gracilis are fully described for the first time. C. gracilis actively initiates an association with H. digitata by approaching and remaining stationary near the actinian.

  10. Micrositios del pasto navajita (Bouteloua gracilis en comunidades de pastizal y de matorral del Altiplano Mexicano

    Directory of Open Access Journals (Sweden)

    Rosalva García-Sánchez

    2005-01-01

    Full Text Available El objetivo de este trabajo fue determinar si hay un tipo de micrositio específico para el establecimiento de Bouteloua gracilis, con patrones recurrentes, en dos diferentes tipos de comunidades vegetales. El pasto navajita azul es una especie perenne de alto valor forrajero y resistente a la sequía. Para ello se realizó un recorrido por tres matorrales y tres pastizales del Altiplano Mexicano; los sitios estudiados fueron elegidos con base en los reportes de ejemplares colectados y herborizados. Los resultados muestran, por un lado, que en los pastizales se presentan micrositios más de tipo funcional que físico, que determinan el establecimiento de B. gracilis, debido principalmente a los altos requerimientos de humedad edáfica de las semillas para germinar y desarrollarse. El micrositio más frecuente que determina el reclutamiento de los individuos provenientes de semilla es el suelo cercano a individuos adultos de su propia especie. Por otro lado, en los matorrales se detectaron, de manera recurrente, varias condiciones de micrositio para la especie y se observó que el tipo de micrositio es determinante, tanto para el establecimiento como para el crecimiento de este y otros pastos; también, el estudio mostró que en comunidades de matorral existe una mayor diversidad de micrositios que en los pastizales, por lo que se concluye que los individuos de B. gracilis, en los matorrales, crecen asociados a micrositios específicos que le brindan protección contra la desecación.

  11. Potentials of Microalgae Biodiesel Production in Nigeria

    African Journals Online (AJOL)

    Prof. Ogunji

    production industries in Nigeria will have positive effects on socio-economic development ... Keywords: bio-energy; climatic conditions; fossil fuel; microalgae; production economics ... of affordable land and labour (Sielhorst et al., ..... by clouds. Closed photobioreactors are scarcely influenced by rainfall pattern; however, ...

  12. 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 ...

  13. 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...

  14. Harvesting of microalgae by bio-flocculation

    NARCIS (Netherlands)

    Salim, S.; Bosma, R.; Vermuë, M.H.; Wijffels, R.H.

    2011-01-01

    The high-energy input for harvesting biomass makes current commercial microalgal biodiesel production economically unfeasible. A novel harvesting method is presented as a cost and energy efficient alternative: the bio-flocculation by using one flocculating microalga to concentrate the

  15. Microalgae biorefineries: The Brazilian scenario in perspective.

    Science.gov (United States)

    Brasil, B S A F; Silva, F C P; Siqueira, F G

    2017-10-25

    Biorefineries have the potential to meet a significant part of the growing demand for energy, fuels, chemicals and materials worldwide. Indeed, the bio-based industry is expected to play a major role in energy security and climate change mitigation during the 21th century. Despite this, there are challenges related to resource consumption, processing optimization and waste minimization that still need to be overcome. In this context, microalgae appear as a promising non-edible feedstock with advantages over traditional land crops, such as high productivity, continuous harvesting throughout the year and minimal problems regarding land use. Importantly, both cultivation and microalgae processing can take place at the same site, which increases the possibilities for process integration and a reduction in logistic costs at biorefinery facilities. This review describes the actual scenario for microalgae biorefineries integration to the biofuels and petrochemical industries in Brazil, while highlighting the major challenges and recent advances in microalgae large-scale production. Copyright © 2016 Elsevier B.V. All rights reserved.

  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. 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

  18. 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.

  19. 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.

  20. hydroprocessing processing processing microalgae derived h

    African Journals Online (AJOL)

    eobe

    higher yield of fuel per unit microalgae than the other ... used for the bio-crude production, it is not mandatory ... convert the whole biomass into primarily liquid .... Typical catalysts reportedly used for hydroprocessing ... design and economics for the conversion of whole ... separate reactors or a two-in-one reactor with a.

  1. Scenario evaluation of open pond microalgae production

    NARCIS (Netherlands)

    Slegers, P.M.; Lösing, M.B.; Wijffels, R.H.; Straten, van G.; Boxtel, van A.J.B.

    2013-01-01

    To evaluate microalgae production in large scale open ponds under different climatologic conditions, a model-based framework is used to study the effect of light conditions, water temperature and reactor design on trends in algae productivity. Scenario analyses have been done for two algae species

  2. 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

  3. Taxonomy of the phyllosoma of Panulirus inflatus (Bouvier, 1895 and P. gracilis Streets, 1871, based on morphometry and molecular analysis

    Directory of Open Access Journals (Sweden)

    Isabel Muñoz-García

    Full Text Available Analysis of wild phyllosoma of Panulirus inflatus (Bouvier, 1895 and P. gracilis Streets, 1871 determined the morphological structures having taxonomic value for differentiation of the two species, in addition to the structures described previously. Of 54 phyllosoma, species identity was confirmed by PCR-restriction fragment length polymorphism (RFLP on 42 P. inflatus and 4 P. gracilis, for which morphology and morphometric measurements were taken. Morphological analysis found subexopodal spines, spines at the base of pereopods 1 and 2, and the mandibles are structures of taxonomic value for differentiating the two species. Morphometric data did not allow differentiation.

  4. Induction of anthocyanin formation and of enzymes related to its biosynthesis by UV light in cell cultures of Haplopappus gracilis

    International Nuclear Information System (INIS)

    Wellmann, E.; Hrazdina, G.; Grisebach, H.

    1976-01-01

    Only UV light below 345 nm stimulates anthocyanin formation in dark grown cell suspension cultures of Haplopappus gracilis. A linear relationship between UV dose and flavonoid accumulation, as found previously with parsley cell cultures was not observed with the H.gracilis cells. Only continuous irradiation with high doses of UV was effective. Drastic increases in the activities of the enzymes phenylalanine ammonia-lyase, chalcone isomerase and flavanone synthase were observed under continuous UV light. The increase in enzyme activities paralleled anthocyanin formation. (author)

  5. Ratio between autoflocculating and target microalgae affects the energy-efficient harvesting by bio-flocculation

    NARCIS (Netherlands)

    Salim, S.; Vermuë, M.H.; Wijffels, R.H.

    2012-01-01

    The effect of ratio between autoflocculating and target microalgae in bio-flocculation was studied with emphasis on the recovery, sedimentation rate and energy demand for harvesting the target microalgae. When the autoflocculating microalgae Ettlia texensis, Ankistrodesmus falcatus and Scenedesmus

  6. In situ proteo-metabolomics reveals metabolite secretion by the acid mine drainage bio-indicator, Euglena mutabilis

    Science.gov (United States)

    Halter, David; Goulhen-Chollet, Florence; Gallien, Sébastien; Casiot, Corinne; Hamelin, Jérôme; Gilard, Françoise; Heintz, Dimitri; Schaeffer, Christine; Carapito, Christine; Van Dorsselaer, Alain; Tcherkez, Guillaume; Arsène-Ploetze, Florence; Bertin, Philippe N

    2012-01-01

    Euglena mutabilis is a photosynthetic protist found in acidic aquatic environments such as peat bogs, volcanic lakes and acid mine drainages (AMDs). Through its photosynthetic metabolism, this protist is supposed to have an important role in primary production in such oligotrophic ecosystems. Nevertheless, the exact contribution of E. mutabilis in organic matter synthesis remains unclear and no evidence of metabolite secretion by this protist has been established so far. Here we combined in situ proteo-metabolomic approaches to determine the nature of the metabolites accumulated by this protist or potentially secreted into an AMD. Our results revealed that the secreted metabolites are represented by a large number of amino acids, polyamine compounds, urea and some sugars but no fatty acids, suggesting a selective organic matter contribution in this ecosystem. Such a production may have a crucial impact on the bacterial community present on the study site, as it has been suggested previously that prokaryotes transport and recycle in situ most of the metabolites secreted by E. mutabilis. Consequently, this protist may have an indirect but important role in AMD ecosystems but also in other ecological niches often described as nitrogen-limited. PMID:22237547

  7. Extending the use of the gracilis muscle flap in perineal reconstruction surgery.

    Science.gov (United States)

    Goldie, Stephen J; Almasharqah, Riyadh; Fogg, Quentin A; Anderson, William

    2016-08-01

    Reconstruction of the perineum is required following oncological resections. Plastic surgical techniques can be used to restore the aesthetics and function of the perineum. The gracilis myocutaneous flap provides a substantial skin paddle, with minimal donor site morbidity. The flap is pedicled on a perforator from the medial circumflex femoral artery, giving it limited reach across the perineum. Tunnelling the flap under the adductor longus muscle may free up more of the arterial pedicle, increasing its reach. On three female cadavers, bilateral gracilis flaps were raised in the standard surgical manner, giving six flaps in total. With the flaps pedicled across the perineum, the distance from the tip of each flap was measured to the anterior superior iliac spine (ASIS). The flaps were then tunnelled under the adductor longus muscle. The distances to the ASIS were measured again. The average pedicle length was greater than 7 cm. Tunnelling the flap under the adductor longus muscle increased the reach by more than 4 cm on average. Cadaveric dissection has shown that tunnelling of the flap in a novel way increase its reach across the perineum. This additional flexibility improves its use clinically and is of benefit to plastic surgeons operating in perineal reconstruction. Copyright © 2016 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

  8. 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...

  9. Free gracilis transfer for smile in children: the Massachusetts Eye and Ear Infirmary Experience in excursion and quality-of-life changes.

    Science.gov (United States)

    Hadlock, Tessa A; Malo, Juan S; Cheney, Mack L; Henstrom, Douglas K

    2011-01-01

    Free muscle transfer for facial reanimation has become the standard of care in recent decades and is now the cornerstone intervention for dynamic smile reanimation. We sought to quantify smile excursion and quality-of-life (QOL) changes in our pediatric free gracilis recipients following reanimation. We quantified gracilis muscle excursion in 17 pediatric patients undergoing 19 consecutive pediatric free gracilis transplantation operations, using our validated SMILE program, as an objective measure of functional outcome. These were compared against excursion measured the same way in a cohort of 17 adults with 19 free gracilis operations. In addition, we prospectively evaluated QOL outcomes in these children using the Facial Clinimetric Evaluation (FaCE) instrument. The mean gracilis excursion in our pediatric free gracilis recipients was 8.8 mm ± 5.0 mm, which matched adult results, but with fewer complete failures of less than 2-mm excursion, with 2 (11%) and 4 (21%), respectively. Quality-of-life measures indicated statistically significant improvements following dynamic smile reanimation (P = .01). Dynamic facial reanimation using free gracilis transfer in children has an acceptable success rate, yields improved commissure excursion, and improves QOL in the pediatric population. It should be considered first-line therapy for children with lack of a meaningful smile secondary to facial paralysis.

  10. 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.

  11. Review on biofuel oil and gas production processes from microalgae

    International Nuclear Information System (INIS)

    Amin, Sarmidi

    2009-01-01

    Microalgae, as biomass, are a potential source of renewable energy, and they can be converted into energy such as biofuel oil and gas. This paper presents a brief review on the main conversion processes of microalgae becoming energy. Since microalgae have high water content, not all biomass energy conversion processes can be applied. By using thermochemical processes, oil and gas can be produced, and by using biochemical processes, ethanol and biodiesel can be produced. The properties of the microalgae product are almost similar to those of offish and vegetable oils, and therefore, it can be considered as a substitute of fossil oil.

  12. 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.

  13. Use of secondary sewage water as a culture medium for Chaetoceros gracilis and Thalassiosira Sp (Chrysophyceae in laboratory conditions

    Directory of Open Access Journals (Sweden)

    Rauquírio André Albuquerque Marinho da Costa

    1999-01-01

    Full Text Available Experiments were carried out in order to test the efficiency of additions of secondary sewage as a culture medium for Chaetoceros gracilis and Thalassiosira sp (Chrysophyceae under laboratory conditions. These algae were cultivated in sea water with concentrations of 10%, 20%, 30% and 40% of wastewater. The results were compared with those obtained by the nutritive medium f2 of Guillard (1975. The best results in terms of cellular densities were observed at 40% additions. There were significant differences (significance levels of 5% between the nutritive medium f2 and the 40% additions for both the species. Maximum cellular densities observed for all additions tested were, 4,125.00 x 10³ cells/ml for Chaetoceros gracilis on the ninth day and 834.00 x 10³ cells/ml for Thalassiosira sp on the fifth day. Biomass was higher in the nutritive medium f2 than in the other treatments, reaching average values of 2,363μg/ml for Chaetoceros gracilis. At all experimental units, the best results were registered at 40% addition for Chaetoceros gracilis, where average values of 0.768μg/ml were observed on the fifth day, and at 30% additions for Thalassiosira sp where 0.883μg/ml were observed on the thirteenth day. It was concluded that secondary sewage could be used as a culture medium for the species tested here, after large scale tests.

  14. Review of the South American characiform fish genus Chilodus, with description of a new species, C. gracilis (Pisces, Characiformes, Chilodontidae)

    NARCIS (Netherlands)

    Isbrücker, I.J.H.; Nijssen, H.

    1988-01-01

    Examination of 291 specimens of Chilodus, a genus of South American fresh water fishes, yielded the presence of three species, viz.: C. punctatus, C. zunevei, and C. gracilis. Of the first species the lectotype is designated. The type material of C. zunevei is lost; new material enabled a

  15. 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.

  16. 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.

  17. Antioxidant activity of the microalga Spirulina maxima

    OpenAIRE

    Miranda M.S.; Cintra R.G.; Barros S.B.M.; Mancini-Filho J.

    1998-01-01

    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 ...

  18. 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.

  19. Innovative natural functional ingredients from microalgae.

    Science.gov (United States)

    Plaza, Merichel; Herrero, Miguel; Cifuentes, Alejandro; Ibáñez, Elena

    2009-08-26

    Nowadays, a wide variety of compounds such as polyphenols, polyunsaturated fatty acids (PUFA), or phytosterols obtained, for example, from wine, fish byproducts, or plants are employed to prepare new functional foods. However, unexplored natural sources of bioactive ingredients are gaining much attention since they can lead to the discovery of new compounds or bioactivities. Microalgae have been proposed as an interesting, almost unlimited, natural source in the search for novel natural functional ingredients, and several works have shown the possibility to find bioactive compounds in these organisms. Some advantages can be associated with the study of microalgae such as their huge diversity, the possibility of being used as natural reactors at controlled conditions, and their ability to produce active secondary metabolites to defend themselves from adverse or extreme conditions. In this contribution, an exhaustive revision is presented involving the research for innovative functional food ingredients from microalgae. The most interesting results in this promising field are discussed including new species composition and bioactivity and new processing and extraction methods. Moreover, the future research trends are critically commented.

  20. 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.

  1. 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)

  2. Free gracilis flap for chest wall reconstruction in male patient with Poland syndrome after implant failure.

    Science.gov (United States)

    Cherubino, Mario; Maggiulli, Francesca; Pellegatta, Igor; Valdatta, Luigi

    2016-01-01

    Poland's syndrome (PS) is a congenital monolateral deformity that may involve breast, chest wall, and upper limb with different degrees of clinical expressions. In some cases, the problem is mainly cosmetic, and the reconstruction should be performed to achieve minimal scarring and donor site morbidity. The authors describe a case report of a male patient with PS who developed a severe capsular contraction after 25 years implant reconstruction, who was treated after explantation using free gracilis flap (FGF). In this patient, only the pectoralis major muscle was missing. An FGF was performed to reconstruct the anterior axillary fold and the soft tissue defect. There was no flap loss, the patient had a clearly improved appearance of the chest wall, and the pain syndrome was solved. In this case report, we demonstrate our experience with the use of an FGF for chest wall reconstruction in male patients with PS after prosthesis explantation.

  3. Free gracilis flap for chest wall reconstruction in male patient with Poland syndrome after implant failure

    Directory of Open Access Journals (Sweden)

    Mario Cherubino

    2016-01-01

    Full Text Available Poland's syndrome (PS is a congenital monolateral deformity that may involve breast, chest wall, and upper limb with different degrees of clinical expressions. In some cases, the problem is mainly cosmetic, and the reconstruction should be performed to achieve minimal scarring and donor site morbidity. The authors describe a case report of a male patient with PS who developed a severe capsular contraction after 25 years implant reconstruction, who was treated after explantation using free gracilis flap (FGF. In this patient, only the pectoralis major muscle was missing. An FGF was performed to reconstruct the anterior axillary fold and the soft tissue defect. There was no flap loss, the patient had a clearly improved appearance of the chest wall, and the pain syndrome was solved. In this case report, we demonstrate our experience with the use of an FGF for chest wall reconstruction in male patients with PS after prosthesis explantation.

  4. 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 ...

  5. 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...

  6. 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.

  7. 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

  8. 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.

  9. USAGE OF ALGAE SPECIES CHAETOMORPHA GRACILIS AND CH. AEREA FOR DEPURATION PROCESS OF THE RESIDUAL WATERS

    Directory of Open Access Journals (Sweden)

    SALARU VICTOR

    2008-11-01

    Full Text Available Rapid increase of the population on the globe scale imposes maximum exploration of the natural resources and first of all of the aquatic resources. As a result are obtained an enormous quantity of residual waters which pollute the waters from rivers, lakes, freatic and underground waters. Elaboration of the depuration methods for residual waters the quantity of which grows continuously, is one of the most up to dated issue of the world. The physical-chemical depuration methods of the residual waters are very expensive and lack the efficiency we would like to have. The most efficient method proved to be the biological method using some species of algae and superior aquatic plants. In our experiences we have involved filamentous green algae Chaetomorpha gracilis and Ch. aerea for depuration of the sewerage water from town Cimishlia. The concentration of the mineral nitrogen compounds in the residual water is around 92,5 mg/l, and of the phosphates 10,1 mg/l. There were used the following concentration of the sewerage water: 10%, 25% and 50%. The most intense development of algae Chaetomorpha aerea was observed in the variant with 10% of residual water, in which the total concentration of the nitrogen was 10,24 mg/l, and of the phosphates 1,05 mg/l. For this variant the depuration water level was about 56,9%. For the case with Chaetomorpha gracilis, the depuration level for the same concentration of the residual water constituted 55,9 %. Increase of the concentration of the polluted water inhibits development of the algae reducing to the minimum their capacity to assimilate the nitrogen and the phosphor. In the solutions with 50 % of residual waters, the algae didn't die, but at the same time they didn't develop. From this results that both algae may be used in the phytoamelioration of the residual waters being diluted at 10% with purified water.

  10. 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

  11. Towards Sustainable Production of Biofuels from Microalgae

    Directory of Open Access Journals (Sweden)

    Hans Ragnar Giselrød

    2008-07-01

    Full Text Available Renewable and carbon neutral biofuels are necessary for environmental and economic sustainability. The viability of the first generation biofuels production is however questionable because of the conflict with food supply. Microalgal biofuels are a viable alternative. The oil productivity of many microalgae exceeds the best producing oil crops. This paper aims to analyze and promote integration approaches for sustainable microalgal biofuel production to meet the energy and environmental needs of the society. The emphasis is on hydrothermal liquefaction technology for direct conversion of algal biomass to liquid fuel.

  12. Redescription of the Indo-West Pacific cardinalfishes (Perciformes: Apogonidae) Rhabdamia spilota Allen Kuiter 1994 and R. gracilis (Bleeker 1856).

    Science.gov (United States)

    Yoshida, Tomohiro; Motomura, Hiroyuki

    2018-01-31

    Rhabdamia spilota Allen Kuiter 1994 (Apogonidae), a poorly known cardinalfish previously known only from the Philippines, Indonesia and the Red Sea, is redescribed on the basis of 70 specimens (20.9-61.2 mm standard length) (including types), from the Indo-West Pacific (Red Sea, Andaman Sea, Japan, South China Sea, the Philippines, Indonesia, New Caledonia, and Australia). Because most reports of the similar species R. gracilis (Bleeker 1856), following its original description, were based on misidentifications, R. gracilis is also redescribed (based on 98 Indo-West Pacific specimens from Seychelles, Maldives, Andaman Sea, Japan, Malaysia, Indonesia, New Caledonia, and Australia, 27.9-59.3 mm standard length); a lectotype is designated for it. Rhabdamia spilota differs from R. gracilis in having 27-33 (mode 30-31) developed gill rakers [vs. 22-27 (mode 24) in the latter], 27-33 (30) gill rakers including rudiments [vs. 23-27 (24-25)], a black stripe from the jaw tips to the anterior margin of the orbit (vs. black pigments only at snout and tip of lower jaw), 3-6 reddish brown to blackish blotches on the opercle and anterior of body (vs. blotches absent), and indistinct black pigment restricted to caudal fin outer margins (vs. pigment scattered over entire fin). Rhabdamia gracilis exhibits sexual dichromatism, female specimens larger than 41.3 mm SL having one or two black stripes on the lateral surface of the body; the stripes are absent in males and smaller females. No evidence of sexual dichromatism was found in R. spilota.

  13. Arthroscopic intra- and extra-articular anterior cruciate ligament reconstruction with gracilis and semitendinosus tendons: a review

    OpenAIRE

    Marcacci, Maurilio; Zaffagnini, Stefano; Marcheggiani Muccioli, Giulio Maria; Neri, Maria Pia; Bondi, Alice; Nitri, Marco; Bonanzinga, Tommaso; Grassi, Alberto

    2011-01-01

    The purposes of this paper are to summarize the concepts relating to the use of a combined intra-articular and extra-articular reconstructive procedure in the arthroscopic treatment of a torn ACL and to review several operative techniques utilizing gracilis and semitendinosus tendons that are currently in use to treat this instability. The highly satisfactory results obtained over the time show that a combination of intra- and extra-articular procedures for ACL reconstruction is a valid surgi...

  14. Influence of gamma radiation and fast neutrons on the growth of Haplopappus gracilis (Nutt) A. Gray callus

    International Nuclear Information System (INIS)

    Cebulska-Wasilewska, A.; Wajda, L.; Korzonek, M.; Polska Akademia Nauk, Krakow. Inst. Fizjologii Roslin)

    1979-01-01

    The sensitivity of the callus of Haplopappus gracilis to gamma radiation and fast neutrons was studied. High doses of radiation cause inhibition of callus growth. At small doses the effect is less pronounced. Stimulation of callus growth was seen. Apart from morphological changes, ionizing radiations lowered the fresh weight ratio of the callus. The RBE value for 5.5 MeV neutrons depended on the dose rate of radiation and the combination of growth medium. (author)

  15. Experience with 32 Pelvic Fracture Urethral Defects Associated with Urethrorectal Fistulas: Transperineal Urethroplasty with Gracilis Muscle Interposition.

    Science.gov (United States)

    Guo, Hailin; Sa, Yinglong; Fu, Qiang; Jin, Chongrui; Wang, Lin

    2017-07-01

    Pelvic fracture urethral defects associated with urethrorectal fistulas are rare and difficult to repair. The aim of this study was to evaluate the efficacy of transperineal urethroplasty with gracilis muscle interposition for the repair of pelvic fracture urethral defects associated with urethrorectal fistulas. We identified 32 patients who underwent transperineal urethroplasty with gracilis muscle interposition to repair pelvic fracture urethral defects associated with urethrorectal fistulas. Patient demographics as well as preoperative, operative and postoperative data were obtained. Mean followup was 33 months (range 6 to 64). The overall success rate was 91% (29 of 32 cases). One-stage repair was successful in 17 of 18 patients (94%) using perineal anastomosis with separation of the corporeal body and in 12 of 14 (86%) using perineal anastomosis with inferior pubectomy and separation of the corporeal body. All 22 patients (100%) without a previous history of repair were successfully treated. However, only 7 of 10 patients (70%) with a previous history of failed urethroplasty and urethrorectal fistula repair were cured. Recurrent urethral strictures developed in 2 cases. One patient was treated successfully with optical internal urethrotomy and the other was treated successfully with tubed perineoscrotal flap urethroplasty. Recurrent urethrorectal fistulas associated with urethral strictures developed in an additional patient. Transperineal urethroplasty with gracilis muscle interposition is a safe and effective surgical procedure for most pelvic fracture urethral defects associated with urethrorectal fistulas. Several other factors may affect its postoperative efficiency. Copyright © 2017 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  16. The accordion gracilis muscle flap: a new design for coverage of recurrent and complicated ischeal pressure sores.

    Science.gov (United States)

    El-Sabbagh, Ahmed H

    2011-10-01

    Management of patients with large or recurrent pressure ulcerations can be complicated by the lack of available local flap, whether already used or because adjacent lesions make such flap insufficient for complete coverage. In this article, the gracilis muscle was modified to cover large defects without help from its cutaneous territory. Twelve ischeal pressure sores were treated between August 2007 and 2009 with the modified gracilis muscle flap in a single-staged procedure. Five ulcers were recurrent and seven patients have associated pressure ulcers. All reconstructions were successful. Mean patient age was 35 years and nearly all patients had multiple significant comorbidities, including associated ulcers, diabetes and urethrocutaneous fistula. All flaps and donor sites healed uneventfully. There was one complication presented as cellulites at the donor site. Follow-up in some cases extend up to 1·5 years. No recurrence was observed. The accordion gracilis muscle flap is a handy, safe and fast flap for reconstruction of recurrent, difficult ischeal pressure sores. © 2011 The Author. © 2011 Blackwell Publishing Ltd and Medicalhelplines.com Inc.

  17. Release of hand burn contracture: comparing the ALT perforator flap with the gracilis free flap with split skin graft.

    Science.gov (United States)

    Misani, M; Zirak, C; Hau, Lê Thua Trung; De Mey, A; Boeckx, W

    2013-08-01

    The use of microsurgery in the management of burn sequelae is not a new idea. According to the properties of various types of free flaps different goals can be achieved or various additional procedures have to be combined. We report the comparison of two different free flaps on a single patient for reconstruction of both upper extremities for burn sequelae. A 1-year-old child sustained severe burns on both hands, arms and thorax and was initially only treated conservatively. This resulted in severe contractures. At the age of 4-years a free gracilis flap was selected for reconstruction of his left hand and a free anterolateral thigh flap for the right hand. We noticed a better functional and esthetic result for the gracilis flap associated with a shorter operative time and a minor donor site morbidity. The intraoperative technique and time, postoperative complications, functional and esthetic results and donor site morbidities were studied in the two types of flaps chosen. A review of literature was also performed. Our experience reported a better success of the gracilis muscle flap covered with a split skin graft compared to the anterolateral thigh flap in the reconstruction of hand function after severe burn sequelae. Copyright © 2013 Elsevier Ltd and ISBI. All rights reserved.

  18. Management of fourth degree obstetric perineal tear without colostomy using non - stimulated gracilis - our experience over eleven years

    Directory of Open Access Journals (Sweden)

    Jiten Kulkarni

    2016-01-01

    Full Text Available Background: Although gracilis muscle transposition for faecal incontinence has been well-described method, its literature for use in obstetric perineal tear without colostomy is sparse. In this study, we have tried to analyse its use in fourth-degree obstetric perineal tears. Patients and Methods: A total of 30 patients with recto-vaginal fistula with faecal incontinence secondary to obstetric perineal tear were retrospectively studied between February 2003 and May 2014. The recto-vaginal fistula was explored, dissected and identification of sphincters was done using muscle stimulator. Fistula closure was done followed by sphincter repair, vaginal tightening procedure and single gracilis transposition. None of the patients had covering colostomy. Faecal incontinence was assessed pre- and post-operatively by digital rectal examination (single examiner, Park's score and Corman's score in all cases and using barium hold and transperineal ultrasonography, manometric studies in a few cases. The outcome was measured at an average follow-up of 8.8 months (7–24 months. Results: As per Park's score 26 patients had Grade I continence, two had Grade II and two patients had Grade III continence. Corman's score improved from fair to excellent in 26 patients. The patients in whom manometry was performed showed a remarkable rise in both resting and squeeze pressures. Two patients developed post-operative infections in upper 1/3 thigh incision site and three patients at gluteal region scar site. Conclusion: Satisfactory continence following gracilis muscle could be achieved.

  19. Photobioreactor cultivation strategies for microalgae and cyanobacteria.

    Science.gov (United States)

    Johnson, Tylor J; Katuwal, Sarmila; Anderson, Gary A; Gu, Liping; Zhou, Ruanbao; Gibbons, William R

    2018-03-08

    The current burden on fossil-derived chemicals and fuels combined with the rapidly increasing global population has led to a crucial need to develop renewable and sustainable sources of chemicals and biofuels. Photoautotrophic microorganisms, including cyanobacteria and microalgae, have garnered a great deal of attention for their capability to produce these chemicals from carbon dioxide, mineralized water, and solar energy. While there have been substantial amounts of research directed at scaling-up production from these microorganisms, several factors have proven difficult to overcome, including high costs associated with cultivation, photobioreactor construction, and artificial lighting. Decreasing these costs will substantially increase the economic feasibility of these production processes. Thus, the purpose of this review is to describe various photobioreactor designs, and then provide an overview on lighting systems, mixing, gas transfer, and the hydrodynamics of bubbles. These factors must be considered when the goal of a production process is economic feasibility. Targets for improving microalgae and cyanobacteria cultivation media, including water reduction strategies will also be described. As fossil fuel reserves continue to be depleted and the world population continues to increase, it is imperative that renewable chemical and biofuel production processes be developed toward becoming economically feasible. Thus, it is essential that future research is directed toward improving these processes. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 2018. © 2018 American Institute of Chemical Engineers.

  20. 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.

  1. 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.

  2. Electrokinetically controlled fluid injection into unicellular microalgae.

    Science.gov (United States)

    Zhou, Xuewen; Zhang, Xixi; Boualavong, Jonathan; Durney, Andrew R; Wang, Tonghui; Kirschner, Scott; Wentz, Michaela; Mukaibo, Hitomi

    2017-10-01

    Electrokinetically controlled microinjection is reported as an effective transport mechanism for microinjection into the wild-type strain of the widely studied model microalga Chlamydomonas reinhardtii. A microinjection system using glass capillary pipettes was developed to capture and impale the motile cells. To apply an electric field and induce electrokinetic flow (e.g., electrophoresis and electroosmosis), an electrode was inserted directly into the solution inside the impaling injection pipette and another electrode was inserted into the external cell media. The viability of the impaled cells was confirmed for more than an hour under 0.01 V using the fluorescein diacetate/propidium iodide dual fluorescent dye based assay. The viability was also found to increase almost logarithmically with decreasing voltage and to depend strongly on the solution within the injection pipette. Successful electrokinetic microinjection into cells was confirmed by both an increase in cell volume under an applied voltage and electric field dependent delivery of fluorescent fluorescein molecules into an impaled cell. Our study offers novel opportunities for quantitative delivery of biomolecules into microalgae and advancing the research and development of these organisms as biosynthetic factories. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Effects of the essential oil of Lippia gracilis Schauer on caulinary shoots of heliconia cultivated in vitro Efeito do óleo essencial de Lippia gracilis Schauer sobre ápices caulinares de heliconia cultivadas in vitro

    Directory of Open Access Journals (Sweden)

    C.C. Albuquerque

    2012-01-01

    Full Text Available The effects of thymol and carvacrol and the essential oil of Lippia gracilis on caulinary shoots of heliconia were evaluated. After disinfection, the shoots were inoculated into MS medium and subjected to the treatments with 420 µL L-1 of essential oil (EO of L. gracilis; 420 µL L-1 of thymol; 420 µL L-1 of carvacrol; 210 µL L-1 of thymol and 210 µL L-1 of carvacrol. The control treatment consisted of the MS medium without any phytoregulators. The main components of EO from L. gracilis are carvacrol, ρ-cimene, and thymol. Seven days after the initiation of the experiments, 36.3% of the control treatment shoots were necrotized, but 90% of the caulinary shoots exposed to EO, thymol, or carvacrol appeared necrotized. Transmission electron microscopy of the shoots revealed that the treatment with EO, thymol, or carvacrol caused the destruction of the plasma cell membranes, and the cell organelles and the nucleus were hardly evident. The EO and its main constituent were toxic to caulinary shoots of heliconia.O efeito do timol, carvacrol e óleo essencial de Lippia gracilis foi observado sobre ápices caulinares de heliconia. Após a desinfestação os ápices foram inoculados em meio MS com os tratamentos de 420 µL L-1 do óleo essencial (OE de L. gracilis; 420 µL L-1 de timol; 420 µL L-1 de carvacrol; 210 µg L-1 de timol e 210 µL L-1 de carvacrol. O tratamento controle consistiu de meio MS sem fitorreguladores. Os principais componentes do OE foram carvacrol, ρ-cimeno e timol. Sete dias após o início do experimento 36,3% dos ápices submetidos ao tratamento controle e 90% dos ápices caulinares expostos ao EO, timol ou carvacrol necrosaram. A microscopia eletrônica de transmissão dos ápices caulinares revelou que os tratamentos com OE, timol e carvacrol provocaram desestruturação da membrana plasmática das células. As organelas e o núcleo não estavam evidentes. O OE e seus principais constituintes foram tóxico para os

  4. Heterotrophic cultivation of microalgae for production of biodiesel.

    Science.gov (United States)

    Mohamed, Mohd Shamzi; Wei, Lai Zee; Ariff, Arbakariya B

    2011-08-01

    High cell density cultivation of microalgae via heterotrophic growth mechanism could effectively address the issues of low productivity and operational constraints presently affecting the solar driven biodiesel production. This paper reviews the progress made so far in the development of commercial-scale heterotrophic microalgae cultivation processes. The review also discusses on patentable concepts and innovations disclosed in the past four years with regards to new approaches to microalgal cultivation technique, improvisation on the process flow designs to economically produced biodiesel and genetic manipulation to confer desirable traits leading to much valued high lipid-bearing microalgae strains.

  5. 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

  6. Isolation, Characterization and Identification of Microalgae from the Red Sea

    KAUST Repository

    Luque Alaní s, Patricio

    2013-01-01

    Eukaryotic microalgae from the Red Sea were isolated, characterized and identified with the purpose of building a culture collection that will serve future research activities in the area of industrial microbiology. Seven sampling locations were

  7. 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

  8. Hydrothermal Disintegration and Extraction of Different Microalgae Species

    Directory of Open Access Journals (Sweden)

    Michael Kröger

    2018-02-01

    Full Text Available For the disintegration and extraction of microalgae to produce lipids and biofuels, a novel processing technology was investigated. The utilization of a hydrothermal treatment was tested on four different microalgae species (Scenedesmus rubescens, Chlorella vulgaris, Nannochloropsis oculata and Arthorspira platensis (Spirulina to determine whether it has an advantage in comparison to other disintegration methods for lipid extraction. It was shown, that hydrothermal treatment is a reasonable opportunity to utilize microalgae without drying and increase the lipid yield of an algae extraction process. For three of the four microalgae species, the extraction yield with a prior hydrothermal treatment elevated the lipid yield up to six times in comparison to direct extraction. Only Scenedesmus rubescens showed a different behaviour. Reason can be found in the different cell wall of the species. The investigation of the differences in cell wall composition of the used species indicate that the existence of algaenan as a cell wall compound plays a major role in stability.

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

    African Journals Online (AJOL)

    Isolation of microalgae species from arid environments and evaluation of their potentials for biodiesel production. ... African Journal of Biotechnology. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives.

  10. Climate conditions, and changes, affect microalgae communities… should we worry?

    Science.gov (United States)

    Gimenez Papiol, Gemma

    2018-03-01

    Microalgae play a pivotal role in the regulation of Earth's climate and its cycles, but are also affected by climate change, mainly by changes in temperature, light, ocean acidification, water stratification, and precipitation-induced nutrient inputs. The changes and impacts on microalgae communities are difficult to study, predict, and manage, but there is no doubt that there will be changes. These changes will have impacts beyond microalgae communities, and many of them will be negative. Some actions are currently ongoing for the mitigation of some of the negative impacts, such as harmful algal blooms and water quality, but global efforts for reducing CO 2 emissions, temperature rises, and ocean acidification are paramount for reducing the impact of climate change on microalgae communities, and eventually, on human well-being. Integr Environ Assess Manag 2018;14:181-184. © 2018 SETAC. © 2018 SETAC.

  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. 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.

  14. 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.

  15. Dipteran larvae and microbes facilitate nutrient sequestration in the Nepenthes gracilis pitcher plant host.

    Science.gov (United States)

    Lam, Weng Ngai; Chong, Kwek Yan; Anand, Ganesh S; Tan, Hugh Tiang Wah

    2017-03-01

    The fluid-containing traps of Nepenthes carnivorous pitcher plants (Nepenthaceae) are often inhabited by organisms known as inquilines. Dipteran larvae are key components of such communities and are thought to facilitate pitcher nitrogen sequestration by converting prey protein into inorganic nitrogen, although this has never been demonstrated in Nepenthes Pitcher fluids are also inhabited by microbes, although the relationship(s) between these and the plant is still unclear. In this study, we examined the hypothesis of digestive mutualism between N. gracilis pitchers and both dipteran larvae and fluid microbes. Using dipteran larvae, prey and fluid volumes mimicking in situ pitcher conditions, we conducted in vitro experiments and measured changes in available fluid nitrogen in response to dipteran larvae and microbe presence. We showed that the presence of dipteran larvae resulted in significantly higher and faster releases of ammonium and soluble protein into fluids in artificial pitchers, and that the presence of fluid microbes did likewise for ammonium. We showed also that niche segregation occurs between phorid and culicid larvae, with the former fragmenting prey carcasses and the latter suppressing fluid microbe levels. These results clarify the relationships between several key pitcher-dwelling organisms, and show that pitcher communities facilitate nutrient sequestration in their host. © 2017 The Author(s).

  16. Expression and characterization of plant aspartic protease nepenthesin-1 from Nepenthes gracilis.

    Science.gov (United States)

    Kadek, Alan; Tretyachenko, Vyacheslav; Mrazek, Hynek; Ivanova, Ljubina; Halada, Petr; Rey, Martial; Schriemer, David C; Man, Petr

    2014-03-01

    Carnivorous plants of the genus Nepenthes produce their own aspartic proteases, nepenthesins, to digest prey trapped in their pitchers. Nepenthesins differ significantly in sequence from other aspartic proteases in the animal or even plant kingdoms. This difference, which also brings more cysteine residues into the structure of these proteases, can be a cause of uniquely high temperature and pH stabilities of nepenthesins. Their detailed structure characterization, however, has not previously been possible due to low amounts of protease present in the pitcher fluid and also due to limited accessibility of Nepenthes plants. In the present study we describe a convenient way for obtaining high amounts of nepenthesin-1 from Nepenthes gracilis using heterologous production in Escherichia coli. The protein can be easily refolded in vitro and its characteristics are very close to those described for a natural enzyme isolated from the pitcher fluid. Similarly to the natural enzyme, recombinant nepenthesin-1 is sensitive to denaturing and reducing agents. It also has maximal activity around pH 2.5, shows unusual stability at high pH and its activity is not irreversibly inhibited even after prolonged incubation in the basic pH range. On the other hand, temperature stability of the recombinant enzyme is lower in comparison with the natural enzyme, which can be attributed to missing N-glycosylation in the recombinant protein. Copyright © 2013 Elsevier Inc. All rights reserved.

  17. Isolation and Characterization of Silaffin that Catalyze Biosilica Formation from Marine Diatom Chaetoceros gracilis

    Directory of Open Access Journals (Sweden)

    AGNES IMELDA MANURUNG

    2007-09-01

    Full Text Available The method of making silica in industries requires extreme conditions. The finding of proteins involved in the formation of biosilica from diatoms, has opened up an alternative way of production. Chaetoceros gracilis is one of the diatoms, which is potential in producing silaffin protein. This study aimed to isolate and to characterize the protein. We also analyzed the protein activity toward tetraethoxyorthosilicate (TEOS substrate in in vitro reaction. Diatom biomass was harvested and further kept in 2% SDS/100 mM EDTA solution. Protein isolation was conducted by dissolving the silica and separating the protein by soaking in 2 M HF/8 M NH4F. Protein concentration was analyzed using Bradford method and the molecular weight was estimated through SDS-PAGE. Protein activity was observed by reacting it with TEOS substrate to form silica polymer and measured by colorimetric molibdate assay. Protein concentration was 1.20 mg/ml and appeared filamentous. The apparent molecular weights consisted of 12, 23, 42, 44 kDa. These protein was able to polymerize the silica at room temperature within 10 min. As much as 85.65 μmol TEOS was polymerized per 1.4 × 106 silaffin protein per min. SEM analysis showed the formation of spherical, aggregate biosilica.

  18. Isolation and Characterization of Silaffin that Catalyze Biosilica Formation from Marine Diatom Chaetoceros gracilis

    Directory of Open Access Journals (Sweden)

    AGNES IMELDA MANURUNG

    2007-09-01

    Full Text Available The method of making silica in industries requires extreme conditions. The finding of proteins involved in the formation of biosilica from diatoms, has opened up an alternative way of production. Chaetoceros gracilis is one of the diatoms, which is potential in producing silaffin protein. This study aimed to isolate and to characterize the protein. We also analyzed the protein activity toward tetraethoxyorthosilicate (TEOS substrate in in vitro reaction. Diatom biomass was harvested and further kept in 2% SDS/100 mM EDTA solution. Protein isolation was conducted by dissolving the silica and separating the protein by soaking in 2 M HF/8 M NH4F. Protein concentration was analyzed using Bradford method and the molecular weight was estimated through SDS-PAGE. Protein activity was observed by reacting it with TEOS substrate to form silica polymer and measured by colorimetric molibdate assay. Protein concentration was 1.20 mg/ml and appeared filamentous. The apparent molecular weights consisted of 12, 23, 42, 44 kDa. These protein was able to polymerize the silica at room temperature within 10 min. As much as 85.65 mol TEOS was polymerized per 1.4 x 106 silaffin protein per min. SEM analysis showed the formation of spherical, aggregate biosilica.

  19. Pedal proportions of Poposaurus gracilis: convergence and divergence in the feet of archosaurs.

    Science.gov (United States)

    Farlow, James O; Schachner, Emma R; Sarrazin, John Cody; Klein, Hendrik; Currie, Philip J

    2014-06-01

    The crocodile-line basal suchian Poposaurus gracilis had body proportions suggesting that it was an erect, bipedal form like many dinosaurs, prompting questions of whether its pedal proportions, and the shape of its footprint, would likewise "mimic" those of bipedal dinosaurs. We addressed these questions through a comparison of phalangeal, digital, and metatarsal proportions of Poposaurus with those of extinct and extant crocodile-line archosaurs, obligate or facultatively bipedal non-avian dinosaurs, and ground birds of several clades, as well as a comparison of the footprint reconstructed from the foot skeleton of Poposaurus with known early Mesozoic archosaurian ichnotaxa. Bivariate and multivariate analyses of phalangeal and digital dimensions showed numerous instances of convergence in pedal morphology among disparate archosaurian clades. Overall, the foot of Poposaurus is indeed more like that of bipedal dinosaurs than other archosaur groups, but is not exactly like the foot of any particular bipedal dinosaur clade. Poposaurus likely had a digitigrade stance, and its footprint shape could have resembled grallatorid ichnotaxa, unless digit I of the foot of Poposaurus commonly left an impression. Copyright © 2014 Wiley Periodicals, Inc.

  20. How to cheat when you cannot lie? Deceit pollination in Begonia gracilis.

    Science.gov (United States)

    Castillo, Reyna A; Caballero, Helga; Boege, Karina; Fornoni, Juan; Domínguez, César A

    2012-07-01

    Mimicry between rewarding and non-rewarding flowers within individuals has been accepted as a strategy favored by selection to deceive pollinators. It has been proposed that this mechanism relies on the exploitation of pollinator's sensory biases, but field evidence is still scarce. In this study, we describe the mechanism of deceit pollination in the monoecious herb Begonia gracilis, a species with exposed rewarding structures (pollen) and intersexual mimicry. Specifically, we test the role of mimicry and exploitation of sensory biases on the reproductive success of male (pollination visitation) and female flowers (probability of setting fruits). We show that pollinators' perception of the amount of reward provided by male flowers is influenced by the independent variation in the sizes of the androecium and the perianth. Large rewarding structures and small perianths were preferred by pollinators, suggesting a central role of the relative size of the rewarding structure on pollinators' foraging decisions. Hence, rewarding male flowers cheat pollinators by exploiting their sensory biases, a strategy followed by non-rewarding female flowers. We suggest that intersexual mimicry operates through the functional resemblance of male flowers' deceit strategy. Artificial manipulation of the flowers supports our findings in natural conditions. Overall, we propose that the continuous and independent variation in the size of the perianth and the reproductive organs among male and female flowers could itself be adaptive.

  1. Transverse musculocutaneous gracilis flap for treatment of capsular contracture in tertiary breast reconstruction.

    Science.gov (United States)

    Pülzl, Petra; Huemer, Georg M; Schoeller, Thomas

    2015-02-01

    Capsular contracture is a common complication associated with implant-based breast reconstruction and augmentation leading to pain, displacement, and rupture. After capsulectomy and implant exchange, the problem often reappears. We performed 52 deepithelialized free transverse musculocutaneous gracilis (TMG) flaps in 33 patients for tertiary breast reconstruction or augmentation of small- and medium-sized breasts. The indications for implant removal were unnatural feel and emotion of their breasts with foreign body feel, asymmetry, pain, and sensation of cold. Anyway, most of the patients did not have a severe capsular contracture deformity. The TMG flap is formed into a cone shape by bringing the tips of the ellipse together. Depending on the contralateral breast, the muscle can also be shaped in an S-form to get more projection if needed. The operating time for unilateral TMG flap breast reconstruction or augmentation was on average 3 hours and for bilateral procedure 5 hours. One patient had a secondary revision of the donor site due to disruption of the normal gluteal fold. Eighty percent of the unilateral TMG flap reconstructions had a lipofilling procedure afterward to correct small irregularities or asymmetry. The advantages of the TMG flap such as short harvesting time, inconspicuous donor site, and the possibility of having a natural breast shape make it our first choice to treat capsular contracture after breast reconstruction and augmentation.

  2. Higher levels of multiple paternities increase seedling survival in the long-lived tree Eucalyptus gracilis.

    Directory of Open Access Journals (Sweden)

    Martin F Breed

    Full Text Available Studying associations between mating system parameters and fitness in natural populations of trees advances our understanding of how local environments affect seed quality, and thereby helps to predict when inbreeding or multiple paternities should impact on fitness. Indeed, for species that demonstrate inbreeding avoidance, multiple paternities (i.e. the number of male parents per half-sib family should still vary and regulate fitness more than inbreeding--named here as the 'constrained inbreeding hypothesis'. We test this hypothesis in Eucalyptus gracilis, a predominantly insect-pollinated tree. Fifty-eight open-pollinated progeny arrays were collected from trees in three populations. Progeny were planted in a reciprocal transplant trial. Fitness was measured by family establishment rates. We genotyped all trees and their progeny at eight microsatellite loci. Planting site had a strong effect on fitness, but seed provenance and seed provenance × planting site did not. Populations had comparable mating system parameters and were generally outcrossed, experienced low biparental inbreeding and high levels of multiple paternity. As predicted, seed families that had more multiple paternities also had higher fitness, and no fitness-inbreeding correlations were detected. Demonstrating that fitness was most affected by multiple paternities rather than inbreeding, we provide evidence supporting the constrained inbreeding hypothesis; i.e. that multiple paternity may impact on fitness over and above that of inbreeding, particularly for preferentially outcrossing trees at life stages beyond seed development.

  3. Dental microwear reveals mammal-like chewing in the neoceratopsian dinosaur Leptoceratops gracilis

    Directory of Open Access Journals (Sweden)

    Frank J. Varriale

    2016-07-01

    Full Text Available Extensive oral processing of food through dental occlusion and orbital mandibular movement is often cited as a uniquely mammalian trait that contributed to their evolutionary success. Save for mandibular translation, these adaptations are not seen in extant archosaurs or lepidosaurs. In contrast, some ornithischian dinosaurs show evidence of precise dental occlusion, habitual intraoral trituration and complex jaw motion. To date, however, a robust understanding of the diversity of jaw mechanics within non-avian dinosaurs, and its comparison with other vertebrates, remains unrealized. Large dental batteries, well-developed dental wear facets, and robust jaws suggests that neoceratopsian (horned dinosaurs were capable chewers. But, biomechanical analyses have assumed a relatively simple, scissor-like (orthal jaw mechanism for these animals. New analyses of dental microwear, presented here, show curvilinear striations on the teeth of Leptoceratops. These features indicate a rostral to caudal orbital motion of the mandible during chewing. A rostrocaudal mandibular orbit is seen in multituberculates, haramiyid allotherians, and some rodents, and its identification in Leptoceratops gracilis is the first evidence of complex, mammal-like chewing in a ceratopsian dinosaur. The term circumpalinal is here proposed to distinguish this new style of chewing from other models of ceratopsian mastication that also involve a palinal component. This previously unrecognized complexity in dinosaurian jaw mechanics indicates that some neoceratopsian dinosaurs achieved a mammalian level of masticatory efficiency through novel adaptive solutions.

  4. 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...

  5. 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.

  6. 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...... by membrane microfiltration and analyzed for fatty acid (GC), triacylglycerol (HPLC), sterol (GC) and tochol (HPLC) composition and also for amounts of phospholipids . Lipid composition in micro algae varied strongly between species....

  7. Microalgal CO2 sequestering – Modeling microalgae production costs

    International Nuclear Information System (INIS)

    Bilanovic, Dragoljub; Holland, Mark; Armon, Robert

    2012-01-01

    Highlights: ► Microalgae production costs were modeled as a function of specific expenses. ► The effects of uncontrollable expenses/factors were incorporated into the model. ► Modeled microalgae production costs were in the range $102–1503 t −1 ha −1 y −1 . - Abstract: Microalgae CO 2 sequestering facilities might become an industrial reality if microalgae biomass could be produced at cost below $500.00 t −1 . We develop a model for estimation of total production costs of microalgae as a function of known production-specific expenses, and incorporate into the model the effects of uncontrollable factors which affect known production-specific expenses. Random fluctuations were intentionally incorporated into the model, consequently into generated cost/technology scenarios, because each and every logically interconnected equipment/operation that is used in design/construction/operation/maintenance of a production process is inevitably subject to random cost/price fluctuations which can neither be eliminated nor a priori controlled. A total of 152 costs/technology scenarios were evaluated to find 44 scenarios in which predicted total production costs of microalgae (PTPCM) was in the range $200–500 t −1 ha −1 y −1 . An additional 24 scenarios were found with PTCPM in the range of $102–200 t −1 ha −1 y −1 . These findings suggest that microalgae CO 2 sequestering and the production of commercial compounds from microalgal biomass can be economically viable venture even today when microalgae production technology is still far from its optimum.

  8. 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.

  9. Techno-Economic Assessment of Micro-Algae Production Systems

    OpenAIRE

    Hoffman, Justin

    2016-01-01

    Global oil consumption is rising at an unprecedented rate renewing interest in alternative fuels. Micro-algae represents a promising feedstock due to inherent advantages such as high solar energy efficiencies, large lipid fractions, and utilization of various waste streams including industrial flue gas. Current technological challenges have limited the commercial viability of microalgae based biofuel production systems. This study directly evaluates and compares the economic viability of biom...

  10. Vibrating membrane filtration as improved technology for microalgae dewatering

    OpenAIRE

    Nurra, C.; Clavero, E.; Salvadó, J.; Torras, C.

    2014-01-01

    10.1016/j.biortech.2014.01.115 The effect of shear-enhanced filtration by vibratory process in microalgae dewatering is presented in this paper. The aim of this research was to investigate the technical performance and improvement of vibrating membrane filtration compared with conventional tangential cross-flow filtration in microalgae concentration. An industrial-scale available commercial set-up was used. Several membrane materials as polyethersulfone, polyacrylonitrile, etc., and mean ...

  11. Bacterial influence on alkenones in live microalgae.

    Science.gov (United States)

    Segev, Einat; Castañeda, Isla S; Sikes, Elisabeth L; Vlamakis, Hera; Kolter, Roberto

    2016-02-01

    The microalga Emiliania huxleyi produces alkenone lipids that are important proxies for estimating past sea surface temperatures. Field calibrations of this proxy are robust but highly variable results are obtained in culture. Here, we present results suggesting that algal-bacterial interactions may be responsible for some of this variability. Co-cultures of E. huxleyi and the bacterium Phaeobacter inhibens resulted in a 2.5-fold decrease in algal alkenone-containing lipid bodies. In addition levels of unsaturated alkenones increase in co-cultures. These changes result in an increase in the reconstructed growth temperature of up to 2°C relative to axenic algal cultures. © 2015 Phycological Society of America.

  12. Marine microalgae attack and feed on metazoans

    DEFF Research Database (Denmark)

    Berge, Terje; Poulsen, Louise K.; Moldrup, Morten

    2012-01-01

    Free-living microalgae from the dinoflagellate genus Karlodinium are known to formmassive blooms in eutrophic coastal waters worldwide and are often associated with fish kills. Natural bloom populations, recently shown to consist of the two mixotrophic and toxic species Karlodinium armiger...... and Karlodinium veneficum have caused fast paralysis and mortality of finfish and copepods in the laboratory, and have been associated with reduced metazooplankton biomass in-situ. Here we show that a strain of K. armiger (K-0688) immobilises the common marine copepod Acartia tonsa in a densitydependent manner...... and collectively ingests the grazer to promote its own growth rate. In contrast, four strains of K. veneficum did not attack or affect the motility and survival of the copepods. Copepod immobilisation by the K. armiger strain was fast (within 15min) and caused by attacks of swarming cells, likely through...

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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

  18. TECHNOLOGICAL APPLICATION OF MICROALGAE IN POWER INDUSTRY AND ENVIRONMENTAL PROTECTION

    Directory of Open Access Journals (Sweden)

    Ilmutdin M. Abdulagatov

    2018-01-01

    Full Text Available Abstract. Aim. The aim of the study is to show the possibility and efficiency of large-scale industrial production of microalgae in the Republic of Dagestan for the development of agriculture (feed for animals and poultry and other technological applications in the food and pharmaceutical industries for the production of algalin flour (eco bread, polyunsaturated fatty acids (omega-3, omega-6 physiologically necessary for humans, biologically active substances (astaxanthin, phycocyanin, new-generation antibiotics, biofuels and other high added value biotechnological products. The problems of using microalgae for bioremediation of the environment, in particular, purification of geothermal waters from phenols before discharging into the sewage system are considered. Methods. Microalgae are grown in closed and open type plants. Valuable algae components can be extracted using supercritical fluid technology of continuous action. Results. We give a comparative evaluation of the efficiency of using microalgae as a biological raw material in comparison with traditionally used oilseeds. Conclusion. For Dagestan, located on the shore of the Caspian Sea, with its warm climate and an abundance of solar and geothermal energy, the development of this technology is a task of great economic importance. The advantages of microalgae technologies are the basis for the creation of large-scale production of microalgae in southern Russia. Biotechnology in Dagestan can become not only profitable, but also a high-tech and innovative industry.

  19. Bioelectricity Production from Microalgae-Microbial Fuel Cell Technology (MMFC

    Directory of Open Access Journals (Sweden)

    da Costa Carlito

    2018-01-01

    Full Text Available Microbial fuel cell is an ecological innovative technology producing bioelectricity by utilizing microbes activity. Substituent energy is produced by changing the chemical energy to electrical energy through the catalytic reaction of microorganism. The research aims to find out the potency of bioelectricity produced by microalgae microbial fuel cell technology by utilizing the combination of tapioca wastewater and microalgae cultivation. This research is conducted through the ingredients preparation stage – microalgae culture, wastewater characterization, membrane and graphite activation, and the providing of other supporting equipment. The next stage is the MMFC arrangement, while the last one is bioelectricity measurement. The result of optimal bioelectricity production on the comparison of electrode 2 : 2, the power density is 44,33 mW/m2 on day 6, meanwhile, on that of 1 : 1, 20,18 mW/m2 power density on day 1 is obtained. It shows that bioelectricity can be produced from the combination of tapioca wastewater and microalgae culture through the microalgae-microbial fuel cell (MMFC technology.This research is expected to be a reference for the next research particularly the one that observes the utilizing of microalgae as the part of new and renewable energy sources.

  20. Una nueva especie de Euglena (Euglenozoa: Euglenales aislada de ambientes extremófilos en las Pailas de Barro del Volcán Rincón de la Vieja, Costa Rica

    Directory of Open Access Journals (Sweden)

    Ana Sittenfeld

    2004-03-01

    Full Text Available Se describe una nueva especie de euglena aislada de las Pailas de Barro Caliente del Volcán Rincón de la Vieja, Costa Rica. Esta especie se caracteriza por habitar sitios ácidos y calientes. Euglena pailasensis sp. nov. tiene como características principales: la ausencia de flagelos, presencia de filamentos similares a "pilis", presencia de cloroplastos con pirenoides atravesados por varios tilacoides, además, es termotolerante y acido-tolerante. Los análisis filogenéticos para el gen ADNr 18S y la secuencia del gen para la enzima Gap C indican que la nueva especie está relacionada con E. mutabilis. Las características taxonómicas basadas en la morfología, biología y secuencia del ADNr 18S y los genes GAP C, son discutidas y comparadas con otras especies relativamente cercanas al géneroAnew species of euglena isolated from a hot and acid mud pool located in Las Pailas de Barro, Volcán Rincón de la Vieja, Costa Rica is described. This species inhabits hot and acid environments. Euglena pailasensis sp. nov. main features are: the absence of flagella, the presence filaments like "pilis", the presence of chloroplasts with pyrenoids crossed by several tylakoids, and acid and heat tolerance. Molecular phylogeny studies using 18S rDNA and Gap C genes indicated that the new species is related to E mutabilis. Its taxonomic characters based on morphology, biology and sequence of the 18S rDNA and Gap C genes are discussed and compared with other closely related species of the genus

  1. Biología pesquera de la langosta Panulirus gracilis en Playa Lagarto, Guanacaste, Costa Rica

    Directory of Open Access Journals (Sweden)

    Helven Naranjo Madrigal

    2011-06-01

    Full Text Available Los parámetros biológicos y pesqueros analizados se fundamentaron en una muestra de 843 langostas provenientes de la actividad pesquera realizada en Playa Lagarto entre noviembre del 2007 y octubre del 2008. Las longitudes cefalotoráxicas de los machos estuvo comprendida entre los 143.6 y 42.8 y 115 y 35.8mm para hembras. El 74.9% de las langostas en los desembarques estuvo por debajo de la talla mínima legal de captura (80 mm de LC. La estructura de tallas muestra un considerable solapamiento de segmentos poblacionales y el incremento de las tallas con la profundidad en donde operan las dos modalidades de pesca estudiadas: el buceo a pulmón y el buceo con compresor. La proporción de sexos obtenida fue de 1.36 M:H. La relación entre LC y peso reveló que las hembras pesan más que los machos de una misma talla y que esta diferencia fue significativa (pBiology and fishery of the lobster Panulirus gracilis in Playa Lagarto, Guanacaste, Costa Rica. Panulirus gracilis is a high valuable lobster species with considerable captures along the tropical Pacific coast. In this study, I present some biological and fishery parameters described after a sample of 843 lobsters, landed in Playa Lagarto from November 2007 to October 2008. From landing records, a total of 74.9% of lobsters were below the minimum legal catch size (80mm CL. Carapace lengths were in the range of 42.8 and 143.6mm for males and 115 and 35.8mm for females. The size structure showed a wide overlapping of population segments, and a trend to increase with depth, where lung diving and “hooka” diving operations take place. Sex ratio was 1.36 M:H. The relationship between weight and LC revealed that females are heavier than males of the same size, and this difference was significant (p<0.05. The von Bertalanffy growth parameters for males and females respectively (K=0.45-0.38, LC∞=166.9-121.7 showed accelerated growth compared to other species. Males observed a higher growth rate

  2. [Genital elephantiasis: reconstructive treatment of penoscrotal lymphoedema with a myocutaneous M. gracilis flap. Experiences from a District Hospital in Ethiopia].

    Science.gov (United States)

    Prica, S; Donati, O F; Schaefer, D J; Peltzer, J

    2008-08-01

    Genital elephantiasis is an illness leading to serious functional and aesthetic as well as psychosocial impairment. Since the 19th century there have been articles describing methods for surgical ablative treatment of penoscrotal lymphoedema. However, most of these methods ignore the creation a new drainage for the lymph. We now describe a new technique using a myocutaneous M. gracilis muscle flap for the reconstruction of the soft tissue damage resulting from radical excision, thus ensuring drainage of the lymph into the deep muscle compartment of the thigh. In the District Hospital "Mettu-Karl Hospital" in the Ethiopian rain forest region of Illubabor, during a period of 6 months the described surgical procedure was applied to 9 patients suffering from severe forms of this grotesquely disfiguring disease. Two patients presented with combined penoscrotal oedema, while the other 7 patients were suffering from isolated scrotal lymphoedema alone. All patients benefited from reconstruction with a myocutaneous M. gracilis muscle flap after radical excision of the affected tissue. All patients were evaluated after 3 and 12 months postoperatively in the presence of a translator. All nine patients showed a functionally and aesthetically satisfying result after 3 months without postoperative occurrence of infection. The evaluation 12 months postoperatively showed no recurrence of genitoscrotal lymphoedema. All patients reported on having regained normal ability for sexual intercourse and no occurrence of urinary tract infections since the operation. Concerning fertility, no statements could be made. A significant improvement in the quality of life was observed by the regained ability to walk and work and consequently the reintegration of the patients into their socio-economic environment. Radical excision of the affected tissue followed by transferring a functioning lymphatic drainage into the deep muscle compartment of the ipsilateral thigh using a proximally based

  3. Experiencia en reconstrucción de tercio distal de pierna con colgajo libre de músculo gracilis

    Directory of Open Access Journals (Sweden)

    A. Conejero

    2013-09-01

    Full Text Available En los defectos de cobertura distales de la pierna con exposición ósea o articular, la transferencia de tejidos libres es frecuentemente la única opción viable. Se utilizan en el rescate de extremidades inferiores en riesgo por trauma, infección, ulceración, quemaduras y tumores. El colgajo libre de músculo gracilis está descrito en la literatura como una excelente alternativa. El objetivo de este estudio es describir las características de los pacientes y resultados de la utilización del colgajo libre de músculo gracilis en la reconstrucción del tercio distal de la pierna. Se trata de un estudio retrospectivo, observacional, de revisión de archivo clínico y fotográfico de 7 pacientes operados por los autores entre los años 2007-2010, 4 hombres y 3 mujeres con un promedio de edad de 38,5 años. El defecto de cobertura que motivó la cirugía (de hasta de 20 x 6 cm fue secundario a fractura expuesta (tipo III de Gustilo y a osteomielitis crónica. La cobertura del colgajo se hizo en todos los casos con injerto dermo-epidérmico. No hubo complicaciones menores ni mayores del sitio donante ni del receptor, con resultados funcionales y estéticos satisfactorios. El colgajo libre de músculo gracilis es una muy buena alternativa para la reconstrucción distal de pierna con defectos de cobertura en fracturas expuestas y osteomielitis o en úlceras crónicas. Tras el seguimiento, todos nuestros pacientes lograron una cobertura completa y estable en el tiempo.

  4. A three-dimensional study of the musculotendinous and neurovascular architecture of the gracilis muscle: application to functional muscle transfer.

    Science.gov (United States)

    Fattah, A Y; Ravichandiran, K; Zuker, R M; Agur, A M R

    2013-09-01

    Muscle transfer is used to restore function typically using a single vector of contraction. Although its use with two independently functional muscular units has been employed, in order to refine this concept we endeavoured to detail the intramuscular anatomy of gracilis, a muscle commonly used for transfer. A novel method to capture intramuscular fibre bundle and neurovascular arrangement was used to create a three-dimensional (3D) digital model that allowed for accurate representation of the relationships between all the intramuscular structures to facilitate flap planning. Twenty gracilis muscles were harvested from 15 cadavers. All components of the muscle were digitised using a Microscribe G2 Digitiser. The data were exported to the 3D animation software Autodesk(®) Maya(®) 2012 whereupon it was rendered into a 3D model that can be exported as static images or videos. Neurovascular anatomy and muscle architecture were analysed from these models, and fibre bundle length, pennation angle and physiological cross-sectional area were calculated from digitised data. The muscle is composed of a variable number of distinct longitudinal segments with muscle fibres spiralling onto the tendon. The main artery to the muscle has three main intramuscular patterns of distribution. The venae comitantes drain discrete zones without intramuscular macroscopic anastomoses. The minor pedicles form an anastomotic chain along the anterior border of the muscle and all vessels were biased to the deep surface. The nerve is related to the vessels in a variable manner and both run between longitudinal muscular compartments. The digitisation technique may be used to advance knowledge of intramuscular architecture and it demonstrated that the gracilis muscle is comprised of four to seven muscular compartments, each representing a functional unit that may theoretically be differentially activated and could be harnessed for more sophisticated muscle transfers. Copyright © 2013 British

  5. Local climate and cultivation, but not ploidy, predict functional trait variation in Bouteloua gracilis (Poaceae)

    Science.gov (United States)

    Butterfield, Bradley J.; Wood, Troy E.

    2015-01-01

    Efforts to improve the diversity of seed 18 resources for important restoration species has become a high priority for land managers in many parts of the world. Relationships between functional trait values and the environment from which seed sources are collected can provide important insights into patterns of local adaptation and guidelines for seed transfer. However, little is known about which functional traits exhibit genetic differentiation across populations of restoration species and thus may contribute to local adaptation. Here, we report the results of a common garden experiment aimed at assessing genetic (including ploidy level) and environmental regulation of several functional traits among populations of Bouteloua gracilis, a dominant C4 grass and the most highly utilized restoration species across much of the Colorado Plateau. We found that leaf size and specific leaf area (SLA) varied significantly among populations, and were strongly correlated with the source population environment from which seeds were collected. However, variation in ploidy level had no significant effect on functional traits. Leaves of plants grown from commercial seed releases were significantly larger and had lower SLA than those from natural populations, a result that is concordant with the overall relation between climate and these two functional traits. We suggest that the patterns of functional trait variation shown here may extend to other grass species in the western USA, and may serve as useful proxies for more extensive genecology research. Furthermore, we argue that care should be taken to develop commercial seed lines with functional trait values that match those of natural populations occupying climates similar to target restoration sites.

  6. Avian-like attributes of a virtual brain model of the oviraptorid theropod Conchoraptor gracilis

    Science.gov (United States)

    Kundrát, Martin

    2007-06-01

    An almost complete adult endoneurocranium of Conchoraptor gracilis Barsbold 1986 (Oviraptoridae; ZPAL MgD-I/95), discovered at the Hermiin Tsav locality (the Upper Cretaceous) in Mongolia, is analyzed. A virtual model of the endoneurocranial cavity was derived from CT scans and represents the most complete maniraptoran endocast to date. It displays reduced olfactory bulbs, large cerebral hemispheres in contact with the expanded cerebellum, an epiphysial projection, optic lobes displaced latero-ventrally, presumptive cerebellar folia, enlarged cerebellar auricles, and a deep medulla oblongata with a prominent ventral flexure. Contrary to Archaeopteryx, the shortened olfactory tract and cerebellum overtopping cerebral hemispheres of Conchoraptor resemble conditions in modern birds. Calculating brain mass relative to body mass indicates that Conchoraptor falls within the range of extant birds, whereas Archaeopteryx occupies a marginal position. Most of the endoneurocranial attributes, however, have a less birdlike appearance in Conchoraptor than do corresponding structures in Archaeopteryx and modern birds in which 1) postero-laterally expanded hemispheral domains broadly overlap the optic lobes, 2) the epiphysis projects to the posterior cerebrum, 3) lateral extension of the optic lobes substantially decreases a brain length-to-width ratio, 4) optic lobe and anterior hindbrain are superposed in lateral view, and 5) cerebellar and midbrain compartments are in distinct superposition. The endoneurocranial characteristics of Conchoraptor, taken together, suggest that the animal had a keen sense of vision, balance, and coordination. The data presented in this study do not allow an unambiguous assessment whether the avian-like endoneurocranial characteristics of the flightless Conchoraptor evolved convergently to those of avian theropods, or indicate a derivation of oviraptorosaurs from volant ancestors.

  7. The transverse musculo-cutaneous gracilis flap for breast reconstruction: How to avoid complications.

    Science.gov (United States)

    Bodin, Frédéric; Dissaux, Caroline; Dupret-Bories, Agnes; Schohn, Thomas; Fiquet, Caroline; Bruant-Rodier, Catherine

    2016-01-01

    The transverse musculocutaneous gracilis (TMG) flap has become a common solution for breast reconstruction. However, the safe skin paddle limits are not yet understood. In this study, we attempted to address this issue based on our experiences with inferior and posterior skin paddle extension. Forty-four breast reconstructions with TMG flaps performed between November 2010 and January 2014 were analyzed retrospectively. For the first 20 cases, the flap skin paddle was extended 3 cm posteriorly to the middle thigh (group 1). For the next 20 flaps (group 2), the posterior tip was limited to this line, whereas more fat was recruited inferiorly. In the four cases of group 3, the skin flap was extended posteriorly with a second vascular pedicle from the profunda artery perforator (PAP) flap. The weights and the dimensions of the flaps, operating durations, and postoperative complications of the entire series were analyzed. Groups 1 and 2 were statistically compared. Flap complications were statistically more frequent in group 1 compared with group 2 (45 vs. 0%, P = 0.0012); 40% posterior flap tip necrosis was observed in group 1. Conversely, donor site complications were statistically more frequent in group 2 than in group 1 (40 vs. 5%, P = 0.019) with 35% inner thigh dehiscence. In the TMG with extended PAP flap group, the operating duration was 77 min longer compared with the rest of the series with no donor site complications. In one case, limited necrosis occurred at the anterior skin tip. Harvesting the posterior portion of the TMG up to the middle of the posterior thigh may lead to partial flap necrosis. Extending subcutaneous fat removal under the inferior skin incision may increase the risk of donor site complications. Adding a second vascular pedicle from the PAP flap may improve posterior TMG tip perfusion at the expense of a longer operation. © 2015 Wiley Periodicals, Inc.

  8. The transverse musculocutaneous gracilis flap for breast reconstruction: guidelines for flap and patient selection.

    Science.gov (United States)

    Schoeller, Thomas; Huemer, Georg M; Wechselberger, Gottfried

    2008-07-01

    The transverse musculocutaneous gracilis (TMG) flap has received little attention in the literature as a valuable alternative source of donor tissue in the setting of breast reconstruction. The authors give an in-depth review of their experience with breast reconstruction using the TMG flap. A retrospective review of 111 patients treated with a TMG flap for breast reconstruction in an immediate or a delayed setting between August of 2002 and July of 2007 was undertaken. Of these, 26 patients underwent bilateral reconstruction and 68 underwent unilateral reconstruction, and 17 patients underwent reconstruction unilaterally with a double TMG flap. Patient age ranged between 24 and 65 years (mean, 37 years). Twelve patients had to be taken back to the operating room because of flap-related problems and nine patients underwent successful revision microsurgically, resulting in three complete flap losses in a series of 111 patients with 154 transplanted TMG flaps. Partial flap loss was encountered in two patients, whereas fat tissue necrosis was managed conservatively in six patients. Donor-site morbidity was an advantage of this flap, with a concealed scar and minimal contour irregularities of the thigh, even in unilateral harvest. Complications included delayed wound healing (n = 10), hematoma (n = 5), and transient sensory deficit over the posterior thigh (n = 49). The TMG flap is more than an alternative to the deep inferior epigastric perforator (DIEP) flap in microsurgical breast reconstruction in selected patients. In certain indications, such as bilateral reconstructions, it possibly surpasses the DIEP flap because of a better concealed donor scar and easier harvest.

  9. Spine micromorphology of normal and hyperhydric Mammillaria gracilis Pfeiff. (Cactaceae) shoots.

    Science.gov (United States)

    Peharec, P; Posilović, H; Balen, B; Krsnik-Rasol, M

    2010-07-01

    Artificial conditions of tissue culture affect growth and physiology of crassulacean acid metabolism plants which often results in formation of hyperhydric shoots. In in vitro conditions Mammillaria gracilis Pfeiff. (Cactaceae) growth switches from organized to unorganized way, producing a habituated organogenic callus which simultaneously regenerates morphologically normal as well as altered hyperhydric shoots. In this study, influence of tissue culture conditions on morphology of cactus spines of normal and hyperhydric shoots was investigated. Spines of pot-grown Mammillaria plants and of in vitro regenerated shoots were examined with stereo microscope and scanning electron microscope. The pot-grown plants had 16-17 spines per areole. In vitro grown normal shoots, even though they kept typical shoot morphology, had lower number of spines (11-12) and altered spine morphology. This difference was even more pronounced in spine number (six to seven) and morphology of the hyperhydric shoots. Scanning electron microscopy analysis revealed remarkable differences in micromorphology of spine surface between pot-grown and in vitro grown shoots. Spines of in vitro grown normal shoots showed numerous long trichomes, which were more elongated on spines of the hyperhydric shoots; the corresponding structures on spine surface of pot-grown plants were noticed only as small protrusions. Scanning electron microscopy morphometric studies showed that the spines of pot-grown plants were significantly longer compared to the spines of shoots grown in tissue culture. Moreover, transverse section shape varies from elliptical in pot-grown plants to circular in normal and hyperhydric shoots grown in vitro. Cluster and correspondence analyses performed on the scanning electron microscope obtained results suggest great variability among spines of pot-grown plants. Spines of in vitro grown normal and hyperhydric shoots showed low level of morphological variation among themselves despite the

  10. 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...... accumulation in microalgae and suggest possibilities for biodiesel production by specific induction of lipid accumulation in miroalgal cultures by cell-cycle inhibition....

  11. Investigation of radiosensitivity and growth dynamics for callus tissues Crepis Capillaris, Haplopappus gracilis, Phasolium vulgaris exposed to gamma radiation

    International Nuclear Information System (INIS)

    Gatsek, Eh.; Glinkova, E.; Ismailova, Eh.N.

    1983-01-01

    Radiosensitivity of three kinds of callus tissues (Crepis capillaris, Haplopappus gracilis, Phasolium vulgaris) manifested in the change of fresh weight after γ-irradiation has been investigated. Irradiated callus arowth showed decrease with increasing doses. It is shown that the radiosensitivity of ''young'' callus tissues is determined by the kind of the plant. Callus of Phaseolis has been found to have the highest radioresistance, while that of Crepis has the lowest one. Radiosensitivity of ''old'' callus tissues is the same for all kinds. Potential mechanism of radiosensitivity of callus tissUes are discussed

  12. Benefits of Microalgae for Human Space Exploration

    Science.gov (United States)

    Verrecchia, Angelique; Bebout, Brad M.; Murphy, Thomas

    2015-01-01

    Algae have long been known to offer a number of benefits to support long duration human space exploration. Algae contain proteins, essential amino acids, vitamins, and lipids needed for human consumption, and can be produced using waste streams, while consuming carbon dioxide, and producing oxygen. In comparison with higher plants, algae have higher growth rates, fewer environmental requirements, produce far less "waste" tissue, and are resistant to digestion and/or biodegradation. As an additional benefit, algae produce many components (fatty acids, H2, etc.) which are useful as biofuels. On Earth, micro-algae survive in many harsh environments including low humidity, extremes in temperature, pH, and as well as high salinity and solar radiation. Algae have been shown to survive inmicro-gravity, and can adapt to high and low light intensity while retaining their ability to perform nitrogen fixation and photosynthesis. Studies have demonstrated that some algae are resistant to the space radiation environment, including solar ultraviolet radiation. It remains to be experimentally demonstrated, however, that an algal-based system could fulfil the requirements for a space-based Bioregenerative Life Support System (BLSS) under comparable spaceflight power, mass, and environmental constraints. Two specific challenges facing algae cultivation in space are that (i) conventional growth platforms require large masses of water, which in turn require a large amount of propulsion fuel, and (ii) most nutrient delivery mechanisms (predominantly bubbling) are dependent on gravity. To address these challenges, we have constructed a low water biofilm based bioreactor whose operation is enabled by capillary forces. Preliminary characterization of this Surface Adhering BioReactor (SABR) suggests that it can serve as a platform for cultivating algae in space which requires about 10 times less mass than conventional reactors without sacrificing growth rate. Further work is necessary to

  13. 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.

  14. 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.

  15. 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

  16. Uptake of uranium from sea water by microalgae

    International Nuclear Information System (INIS)

    Sakaguchi, Takashi; Horikoshi, Takao; Nakajima, Akira

    1978-01-01

    The uptake of uranium from aqueous systems especially from sea water by various microalgae was investigated. The freshwater microalgae, Chlorella regularis, Scenedesmus bijuga, Scenedesmus chloreloides, Scenedesmus obliquus, Chlamydomonas angulosa, Chlamydomonas reinhardtii, accumulated relatively large amounts of uranium from the solution containing uranium only. The concentration factors of the above mentioned algae were: Chlorella regularis 3930, Chlamydomonas 2330 - 3400, Scenedesmus 803 - 1920. The uptake of uranium from sea water by Chlorella regularis was inhibited markedly by the co-existence of carbonate ions. Chlorella cells could take up a great quantity of uranium from decarbonated sea water. The uptake of uranium was affected by the pH of sea water, and the amount of uranium absorbed was maximum at pH 5. The experiment was carried out to screen marine microalgae which have the ability to accumulate a large amount of uranium from sea water. The uptake of uranium from sea water by marine microalgae of different species turned out to be in the following decreasing order: Synechococcus > Chlamydomonas >> Chlorella > Dunaliella > Platymonas > Calothrix > Porphyridium. The amount of uranium absorbed differed markedly with different species of marine microalgae. (author)

  17. 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.

  18. 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.

  19. 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.

  20. Descripción ultraestructural de Euglena pailasensis (Euglenozoa del Volcán Rincón de la Vieja, Guanacaste, Costa Rica

    Directory of Open Access Journals (Sweden)

    Ethel Sánchez

    2004-03-01

    H 2 - 4. The hot mud pool is located in Area de Pailas de Barro, Las Pailas, Rincón de la Vieja Volcano, Guanacaste, Costa Rica. The morphological characterization of the Euglena pailasensis was performed by SEM and TEM. It was determined that, although the euglenoid was obtained from an extreme volcanic environment, the general morphology corresponds to that of a typical member of Euglena of 30-45 µm long and 8-10 µm wide, with membrane, pellicle, chloroplasts, mitochondria, nucleus, pigments and other cytoplasmic organelles. E. pailasensis is delimited by a membrane and by 40 to 90 pellicle strips. It was observed up to 5 elongated chloroplasts per cell. The chloroplast contains several osmiophilic globules and a pyrenoid penetrated by few thylakoid pairs. The nutritious material is reserved in numerous small paramylon grains located at the center of the cell, mitocondria are characterized by the presence of crests in radial disposition toward the interior of the lumen. It was also observed around the external surface "pili" like filaments originating from the pellicle strips. There is no evidence for the presence of flagella in the ampulla (reservoir/canal area, a fact confirmed by negative staining, and a difference regarding other species of Euglena. The observed ultrastructural characteristics are not sufficient to explain the adaptation of this species to acid and hot environments

  1. 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

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. A tangled tale of two teal: Population history of the grey Anas gracilis and chestnut teal a. castanea of Australia

    Science.gov (United States)

    Joseph, L.; Adcock, G.J.; Linde, C.; Omland, K.E.; Heinsohn, R.; Terry, Chesser R.; Roshier, D.

    2009-01-01

    Two Australian species of teal (Anseriformes: Anatidae: Anas), the grey teal Anas gracilis and the chestnut teal A. castanea, are remarkable for the zero or near-zero divergence recorded between them in earlier surveys of mitochondrial DNA (mtDNA) diversity. We confirmed this result through wider geographical and population sampling as well as nucleotide sampling in the more rapidly evolving mtDNA control region. Any data set where two species share polymorphism as is the case here can be explained by a model of gene flow through hybridization on one hand or by incomplete lineage sorting on the other hand. Ideally, analysis of such shared polymorphism would simultaneously estimate the likelihood of both phenomena. To do this, we used the underlying principle of the IMa package to explore ramifications to understanding population histories of A. gracilis and A. castanea. We cannot reject that hybridization occurs between the two species but an equally or more plausible finding for their nearly zero divergence is incomplete sorting following very recent divergence between the two, probably in the mid-late Pleistocene. Our data add to studies that explore intermediate stages in the evolution of reciprocal monophyly and paraphyletic or polyphyletic relationships in mtDNA diversity among widespread Australian birds. ?? 2009 J. Avian Biol.

  9. Clinical and radiological outcomes after a quasi-anatomical reconstruction of medial patellofemoral ligament with gracilis tendon autograft.

    Science.gov (United States)

    Monllau, Joan C; Masferrer-Pino, Àngel; Ginovart, Gerard; Pérez-Prieto, Daniel; Gelber, Pablo E; Sanchis-Alfonso, Vicente

    2017-08-01

    To analyse the clinical and radiological outcomes of a quasi-anatomical reconstruction of the medial patellofemoral ligament (MPFL) with a gracilis tendon autograft. Patients with objective recurrent patellar instability that were operated on from 2006 to 2012 were included. A quasi-anatomical surgical technique was performed using a gracilis tendon autograft. It was anatomically attached at the patella, and the adductor magnus tendon was also used as a pulley for femoral fixation (non-anatomical reconstruction). The IKDC, Kujala and Lysholm scores as well as Tegner and VAS for pain were collected preoperatively and at final follow-up. Radiographic measurements of patellar position tilt and signs of osteoarthritis (OA) as well as trochlear dysplasia were also recorded. Thirty-six patients were included. The mean age at surgery was 25.6 years. After a minimum 27 months of follow-up, all functional scores significantly improved (p patellofemoral surfaces at the short term, as shown by the absence of radiological signs of OA in the CT scan. The procedure has been shown to be safe and suitable for the treatment of chronic patellar instability, including in adolescents with open physis. A new effective, inexpensive and easy-to-perform technique is described to reconstruct MPFL in the daily clinical practice. Therapeutic case series, Level IV.

  10. NÚMERO CROMOSSÔMICO DE Lippia gracilis Schauer (VERBENACEAE OCORRENTES NO ESTADO DO RIO GRANDE DO NORTE, BRASIL

    Directory of Open Access Journals (Sweden)

    LUIS EDUARDO DE SOUSA SOARES

    2011-01-01

    Full Text Available The genus Lippia (Verbenaceae comprises about 200 species of pantropical distribution. Lippia gracilis Schauer, popularly known as the mountain balm, is an aromatic plant, native of northeastern Brazil, used in folk medicine as an antiseptic and to treat dermatitis. Although cytogenetic serve as a tool in taxonomy rate, cytogenetical studies of genus Lippia are restricted. Given the above, the present study aimed to determine, at the first time, the chromosome number of copies of L. gracilis, and thereby contribute to a better taxonomic understanding of this genus. In this sense root tips collected from newly planted specimens were pretreated with a solution of 2mM 8-hydroxyquinoline for 4 hours, fixed in Carnoy 3:1 (ethanol: acetic acid for 24 hours and stored in the same fixative for later analysis. The roots were hydrolyzed in 5N HCl for 20 minutes and the slides, prepared by squashing in acetic acid (45% and stained with 2% Giemsa. The best metaphases were photographed and pointed to the chromosome number 2n = 24. Moreover, were observed metacentric and submetacentric chromosomes. Because there are several chromosome numbers in the genus, from n=10 to n=30, and as the same is little known cytogenetically, f more comprehensive cytogenetic studies are necessary, involving a larger number of species, so these data may help to clarify taxonomic inconsistencies in the family Verbenaceae.

  11. 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.

  12. 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.

  13. Multi-Product Microalgae Biorefineries: From Concept Towards Reality.

    Science.gov (United States)

    't Lam, G P; Vermuë, M H; Eppink, M H M; Wijffels, R H; van den Berg, C

    2018-02-01

    Although microalgae are a promising biobased feedstock, industrial scale production is still far off. To enhance the economic viability of large-scale microalgae processes, all biomass components need to be valorized, requiring a multi-product biorefinery. However, this concept is still too expensive. Typically, downstream processing of industrial biotechnological bulk products accounts for 20-40% of the total production costs, while for a microalgae multi-product biorefinery the costs are substantially higher (50-60%). These costs are high due to the lack of appropriate and mild technologies to access the different product fractions such as proteins, carbohydrates, and lipids. To reduce the costs, simplified processes need to be developed for the main unit operations including harvesting, cell disruption, extraction, and possibly fractionation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. Thermogravimetric analysis of the gasification of microalgae Chlorella vulgaris.

    Science.gov (United States)

    Figueira, Camila Emilia; Moreira, Paulo Firmino; Giudici, Reinaldo

    2015-12-01

    The gasification of microalgae Chlorella vulgaris under an atmosphere of argon and water vapor was investigated by thermogravimetric analysis. The data were interpreted by using conventional isoconversional methods and also by the independent parallel reaction (IPR) model, in which the degradation is considered to happen individually to each pseudo-component of biomass (lipid, carbohydrate and protein). The IPR model allows obtaining the kinetic parameters of the degradation reaction of each component. Three main stages were observed during the gasification process and the differential thermogravimetric curve was satisfactorily fitted by the IPR model considering three pseudocomponents. The comparison of the activation energy values obtained by the methods and those found in the literature for other microalgae was satisfactory. Quantification of reaction products was performed using online gas chromatography. The major products detected were H2, CO and CH4, indicating the potential for producing fuel gas and syngas from microalgae. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. Advances and perspectives in using microalgae to produce biodiesel

    International Nuclear Information System (INIS)

    Amaro, Helena M.; Guedes, A. Catarina; Malcata, F. Xavier

    2011-01-01

    Carbon-neutral renewable liquid biofuels are needed to displace petroleum-derived transport fuels in the near future - which contribute to global warming and are of a limited availability. A promising alternative is conveyed by microalgae, the oil content of which may exceed 80% (w/w DW ) - as compared with 5% of the best agricultural oil crops. However, current implementation of microalga-based systems has been economically constrained by their still poor volumetric efficiencies - which lead to excessively high costs, as compared with petrofuel prices. Technological improvements of such processes are thus critical - and this will require a multiple approach, both on the biocatalyst and bioreactor levels. Several bottlenecks indeed exist at present that preclude the full industrial exploitation of microalgal cells: the number of species that have been subjected to successful genetic transformation is scarce, which hampers a global understanding (and thus a rational design) of novel blue-biotechnological processes; the mechanisms that control regulation of gene expression are not fully elucidated, as required before effective bioprocesses based on microalgae can be scaled-up; and new molecular biology tools are needed to standardize genetic modifications in microalgae - including efficient nuclear transformation, availability of promoter or selectable marker genes, and stable expression of transgenes. On the other hand, a number of pending technological issues are also present: the relatively low microalga intrinsic lipid productivity; the maximum cell concentration attainable; the efficiency of harvest and sequential recovery of bulk lipids; and the possibility of by-product upgrade. This review briefly covers the state of the art regarding microalgae toward production of biofuels, both from the point of view of the microalgal cell itself and of the supporting bioreactor; and discusses, in a critical manner, current limitations and promising perspectives in this

  5. Microalgae as a raw material for biofuels production.

    Science.gov (United States)

    Gouveia, Luisa; Oliveira, Ana Cristina

    2009-02-01

    Biofuels demand is unquestionable in order to reduce gaseous emissions (fossil CO(2), nitrogen and sulfur oxides) and their purported greenhouse, climatic changes and global warming effects, to face the frequent oil supply crises, as a way to help non-fossil fuel producer countries to reduce energy dependence, contributing to security of supply, promoting environmental sustainability and meeting the EU target of at least of 10% biofuels in the transport sector by 2020. Biodiesel is usually produced from oleaginous crops, such as rapeseed, soybean, sunflower and palm. However, the use of microalgae can be a suitable alternative 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; they have fast growth rate, permit the use of non-arable land and non-potable water, use far less water and do not displace food crops cultures; their production is not seasonal and they can be harvested daily. The screening of microalgae (Chlorella vulgaris, Spirulina maxima, Nannochloropsis sp., Neochloris oleabundans, Scenedesmus obliquus and Dunaliella tertiolecta) was done in order to choose the best one(s), in terms of quantity and quality as oil source for biofuel production. Neochloris oleabundans (fresh water microalga) and Nannochloropsis sp. (marine microalga) proved to be suitable as raw materials for biofuel production, due to their high oil content (29.0 and 28.7%, respectively). Both microalgae, when grown under nitrogen shortage, show a great increase (approximately 50%) in oil quantity. If the purpose is to produce biodiesel only from one species, Scenedesmus obliquus presents the most adequate fatty acid profile, namely in terms of linolenic and other polyunsaturated fatty acids. However, the microalgae Neochloris oleabundans, Nannochloropsis sp. and Dunaliella tertiolecta can also be used if associated with other

  6. 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.

  7. 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.

  8. Potency of Microalgae as Biodiesel Source in Indonesia

    Directory of Open Access Journals (Sweden)

    H Hadiyanto

    2012-02-01

    Full Text Available Within 20 years, Indonesia should find another energy alternative to substitute current 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, however the utilization of microalgae as biofuel production is still limited. The biodiesel from current sources (Jatropha, palm oil, and sorghum is still not able to cover all the needs if the fossil oil cannot be explored anymore. In this paper, the potency of microalgae in Indonesia was analysed as the new potential of energy (biodiesel sources.

  9. 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

  10. Nanosilver microalgae biosynthesis: cell appearance based on SEM and EDX methods

    Science.gov (United States)

    Pancasakti Kusumaningrum, Hermin; Zainuri, Muhammad; Marhaendrajaya, Indras; Subagio, Agus

    2018-05-01

    Microbial contamination has caused public health problems in the world population. This problem has spurred the development of methods to overcome and prevent microbial invasion. The extensive use of antibiotics has facilitated the continued emergence and spread of resistant organisms. Synthesized of silver nanoparticle (AgNPs) on microalgae Chlorella pyrenoidosa offer environmentally safe antimicrobial agent. The present study is focused on the biosynthesis of AgNPs using microalgae C. pyrenoidosa. The research methods was conducted by insertion of nanosilver particle into microalgae cells with and without agitation to speed up the process of formation nanosilver microalgae. The formation of microalgae SNP was analyzes by UV-Vis spectrophotometer, Scanning Electron Micrograph (SEM) and Energy-dispersive X-ray spectroscopy (EDX) methods. The research result showed that nanosilver microalgae biosynthesis using the agitation treatment was exhibited better performance in particle insertion and cell stability, comparing with no agitation treatment. However, synthesis of nanosilver microalgae tend to reduce the cell size.

  11. Acaricidal efficacies of Lippia gracilis essential oil and its phytochemicals against organophosphate-resistant and susceptible strains of Rhipicephalus (Boophilus) microplus

    Science.gov (United States)

    Plant-derived natural products can serve as an alternative to synthetic compounds for control of ticks of veterinary and medical importance. Lippia gracilis is an aromatic plant that produces essential oil with high content of carvacrol and thymol monoterpenes. These monoterpenes have high acaricida...

  12. Wet torrefaction of microalga Chlorella vulgaris ESP-31 with microwave-assisted heating

    International Nuclear Information System (INIS)

    Bach, Quang-Vu; Chen, Wei-Hsin; Lin, Shih-Cheng; Sheen, Herng-Kuang; Chang, Jo-Shu

    2017-01-01

    Highlights: • A microwave-assisted heating system is used for wet torrefaction (WT) of microalga. • Microalga Chlorella vulgaris ESP-31 is adopted as the feedstock. • The ash content in the microalga is reduced after WT. • The calorific value of the microalga can be intensified up to 21% after WT. • At least 61.5% of energy in the biomass is retained after WT. - Abstract: Microalgae are a prime source of third generation biofuels. Many thermochemical processes can be applied to convert them into fuels and other valuable products. However, some types of microalgae are characterized by very high moisture and ash contents, thereby causing several problems in further conversion processes. This study presents wet torrefaction (WT) as a promising pretreatment method to overcome the aforementioned drawbacks coupled with microalgal biomass. For this purpose, a microwave-assisted heating system was used for WT of microalga Chlorella vulgaris ESP-31 at different reaction temperatures (160, 170, and 180 °C) and durations (5, 10, and 30 min). The results show several improvements in the fuel properties of the microalga after WT such as increased calorific value and hydrophobicity as well as reduced ash content. A correlation in terms of elemental analysis can be adopted to predict the higher heating value of the torrefied microalga. The structure analysis by Fourier transform infrared (FT-IR) spectroscopy reveals that the carbohydrate content in the torrefied microalgae is lowered, whereas their protein and lipid contents are increased if the WT extent is not severe. However, the protein and lipid contents are reduced significantly at more severe WT conditions. The thermogravimetric analysis shows that the torrefied microalgae have lower ignition temperatures but higher burnout temperatures than the raw microalga, revealing significant impact of WT on the combustion reactivity of the microalga. Overall, the calorific value of the microalga can be intensified up to

  13. Catch composition of the spiny lobster Panulirus gracilis (Decapoda: Palinuridae off the western coast of Mexico Composición de la captura de la langosta espinosa Panulirus gracilis (Decapoda: Palinuridae en la costa oeste de México

    Directory of Open Access Journals (Sweden)

    Raúl Pérez-González

    2011-07-01

    Full Text Available The lobster fishery in the Gulf of California and the south-central region of the western coast of Mexico consists of small-scale artisanal activity supported by Panulirus gracilis and P. inflatus, with an annual average catch of 132 ton. The present study analyzes the landing composition of this fishery and the population structure of P. gracilis. Carapace lengths (CL for this species ranged from 35 to 125 mm, and the most frequent sizes were between 60 and 85 mm. The size distribution was approximately normal. This implies that the fishery is composed of several size classes, with annual recruitment to the fishing areas. For the 1989-1990 and 1990-1991 fishing seasons, the mean monthly sizes of males were between 70.18 ± 11.74 and 81.11 ± 6.76 mm CL, whereas females averaged from 73.60 ± 8.95 to 80.28 ± 7.53 mm CL. Power-law relationships between carapace length (CL in mm and total weight (TW in g were determined, resulting in the following equations: PT = 0.0021 CL27689 for males and PT = 0.0009 CL³ 0038 for females. During certain periods of the year, males dominated the catch; however, the overall annual male:female ratio was near 1:1.La pesquería de langosta en el golfo de California y en el centro-sur de la costa occidental de México es una actividad artesanal a pequeña escala y es sostenida por Panulirus gracilis y P. inflatus, con una captura promedio anual de 132 ton. En este estudio se analiza la composición de los desembarques de esta pesquería y la estructura de la población de P. gracilis. El intervalo de talla de esta especie fue de 35 a 125 mm de longitud del cefalotórax (LC y el más frecuente se encontró entre 60 y 85 mm. La distribución de tallas fue aproximadamente normal. Esto implica que la pesquería está compuesta por varias clases de tallas, con un reclutamiento anual a las áreas de pesca. La talla media mensual de machos fue entre 70,18 ± 11,74 y 81,11 ± 6,76 mm LC y en hembras de 73,60 ± 8,95 a 80

  14. Management of autotrophic mass cultures of micro-algae

    CSIR Research Space (South Africa)

    Toerien, DF

    1987-01-01

    Full Text Available Interest in the mass cultivation of micro-algae as feed and foodstuff has existed since the turn of the century (Robinson and Toerien, 1962). Experiments using algae in photosynthetic research (Warburg, 1919) also led to an appreciation...

  15. 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.

  16. 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

  17. 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

  18. Potential of industrial biotechnology with cyanobacteria and eukaryotic microalgae

    NARCIS (Netherlands)

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

    2013-01-01

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

  19. 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...

  20. 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.

  1. 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 ...

  2. 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

  3. 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,

  4. 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

  5. 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

  6. 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.

  7. Microalgae respond differently to nitrogen availability during culturing

    Indian Academy of Sciences (India)

    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 Trachydiscus ...

  8. 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).

  9. Biodiesel production with microalgae as feedstock: from strains to biodiesel.

    Science.gov (United States)

    Gong, Yangmin; Jiang, Mulan

    2011-07-01

    Due to negative environmental influence and limited availability, petroleum-derived fuels need to be replaced by renewable biofuels. Biodiesel has attracted intensive attention as an important biofuel. Microalgae have numerous advantages for biodiesel production over many terrestrial plants. There are a series of consecutive processes for biodiesel production with microalgae as feedstock, including selection of adequate microalgal strains, mass culture, cell harvesting, oil extraction and transesterification. To reduce the overall production cost, technology development and process optimization are necessary. Genetic engineering also plays an important role in manipulating lipid biosynthesis in microalgae. Many approaches, such as sequestering carbon dioxide from industrial plants for the carbon source, using wastewater for the nutrient supply, and maximizing the values of by-products, have shown a potential for cost reduction. This review provides a brief overview of the process of biodiesel production with microalgae as feedstock. The methods associated with this process (e.g. lipid determination, mass culture, oil extraction) are also compared and discussed.

  10. Ingestion of Brachionus plicatilis under different microalgae conditions

    Science.gov (United States)

    Zhou, Wenli; Tang, Xuexi; Qiao, Xiuting; Wang, You; Wang, Renjun; Feng, Lei

    2009-09-01

    The effects of four microalgae, Chlorella vulgaris, Platymonas helgolandicavar, Isochrysis galbana, and Nitzschia closterium on the grazing and filtering rates of the marine rotifer, Brachionus plicatilis, were evaluated under laboratory conditions. The grazing rates in separate cultures of the four microalga were as follows: C. vulgaris > P. helgolandicavar > I. galbana > N. closterium. However, the filtering rates occurred in the following order: P. helgolandicavar > N. closterium > C. vulgaris > I. galbana. A mixed diets experiment revealed that P. helgolandicavar was the preferred diet of B. plicatilis. In addition, the grazing rate of B. plicatilis increased gradually as the density of the microalgae increased, until concentrations of 2.5×106 cells mL-1 for C. vulgaris and 1.5×106 cells mL-1 for I. galbana were obtained. Furthermore, the filtering rate increased slightly when the density of the microalgae was low, after which it declined as the microalgal density increased. The grazing rates of B. plicatilis were as follows during the different growth phases: stationary phase > exponential phase > lag phase > decline phase. Additionally, the filtering rates during the growth phases were: exponential phase > lag phase > stationary phase > decline phase. The results of this study provide foundational information that can be used to explore the optimal culture conditions for rotifers and to promote the development of aquaculture.

  11. Production of bio-jet fuel from microalgae

    Science.gov (United States)

    Elmoraghy, Marian

    The increase in petroleum-based aviation fuel consumption, the decrease in petroleum resources, the fluctuation of the crude oil price, the increase in greenhouse gas emission and the need for energy security are motivating the development of an alternate jet fuel. Bio-jet fuel has to be a drop in fuel, technically and economically feasible, environmentally friendly, greener than jet fuel, produced locally and low gallon per Btu. Bic jet fuel has been produced by blending petro-based jet fuel with microalgae biodiesel (Fatty Acid Methyl Ester, or simply FAME). Indoor microalgae growth, lipids extraction and transetrification to biodiesel are energy and fresh water intensive and time consuming. In addition, the quality of the biodiesel product and the physical properties of the bio-jet fuel blends are unknown. This work addressed these challenges. Minimizing the energy requirements and making microalgae growth process greener were accomplished by replacing fluorescent lights with light emitting diodes (LEDs). Reducing fresh water footprint in algae growth was accomplished by waste water use. Microalgae biodiesel production time was reduced using the one-step (in-situ transestrification) process. Yields up to 56.82 mg FAME/g dry algae were obtained. Predicted physical properties of in-situ FAME satisfied European and American standards confirming its quality. Lipid triggering by nitrogen deprivation was accomplished in order to increase the FAME production. Bio-jet fuel freezing points and heating values were measured for different jet fuel to biodiesel blend ratios.

  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. 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.

  14. 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.

  15. 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

  16. 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 ...

  17. 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

  18. 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.

  19. 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

  20. 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

  1. 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

  2. Analysis and stability of fatty acid esterified xanthophylls from microalgae

    NARCIS (Netherlands)

    Weesepoel, Y.J.A.

    2014-01-01

    Fatty acid esterified xanthophylls (e.g. astaxanthin) produced by microalgae are regarded as a natural alternative for food colourants, but little is known on the stability of these compounds in foods. The aims of this research were (i) to develop protocols to analyze esterified

  3. Vibrating membrane filtration as improved technology for microalgae dewatering.

    Science.gov (United States)

    Nurra, Claudia; Clavero, Ester; Salvadó, Joan; Torras, Carles

    2014-04-01

    The effect of shear-enhanced filtration by vibratory process in microalgae dewatering is presented in this paper. The aim of this research was to investigate the technical performance and improvement of vibrating membrane filtration compared with conventional tangential cross-flow filtration in microalgae concentration. An industrial-scale available commercial set-up was used. Several membrane materials as polyethersulfone, polyacrylonitrile, etc., and mean pore sizes (from 7000Da to 0.2μm) were tested and compared in both filtration set-ups. Experiments were carried-out with Nannochloropsis gaditana and Phaeodactylum tricornutum microalgae. It has been demonstrated that, even if the choice of the membrane depends on its cut-off, its material and the type of microalgae filtrated, dynamic filtration is always the best technology over a conventional one. If with conventional filtration permeability values were in the vicinity of 10L/h/m(2)/bar in steady state phase, with dynamic filtration these values increased to 30L/h/m(2)/bar or more. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. 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

  5. Suitability of Nigerian Weather Conditions for Cultivation of Microalgae

    African Journals Online (AJOL)

    Client

    compared with optimal conditions for cultivation of various species of microalgae. ... The results of average hours of sunshine showed that Jos has the lowest number of hours ... Temperature stratification in ponds within Abakaliki was ... question of how we will feed the starving masses of our ever increasing world population.

  6. Morphological Identification and Single-Cell Genomics of Marine Diplonemids

    Czech Academy of Sciences Publication Activity Database

    Gawryluk, R. M. R.; del Campo, J.; Okamoto, n.; Strassert, J. F. H.; Lukeš, Julius; Richards, T.A.; Worden, A.Z.; Santoro, A. E.; Keeling, P. J.

    2016-01-01

    Roč. 26, č. 22 (2016), s. 3053-3059 ISSN 0960-9822 Institutional support: RVO:60077344 Keywords : Euglena gracilis * introns * genes * annotation * RNA Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 8.851, year: 2016

  7. Effects of mixed substrates on growth and vitamin production by ...

    African Journals Online (AJOL)

    SERVER

    2007-10-16

    Oct 16, 2007 ... The cells were grown mixotrophically in glucose (G), ethanol ... Key words: mixed substrate culture, Euglena gracilis, cell growth, vitamin production. ..... Biological elimination of nitric oxide from fuel gas by marine micro-.

  8. Use of alternative media and different types of recipients in a laboratory culture of Ankistrodesmus gracilis (Reinsch Korshikov (Chlorophyceae - doi: 10.4025/actascibiolsci.v33i3.8046 Use of alternative media and different types of recipients in a laboratory culture of Ankistrodesmus gracilis (Reinsch Korshikov (Chlorophyceae - doi: 10.4025/actascibiolsci.v33i3.8046

    Directory of Open Access Journals (Sweden)

    Flávia de Almeida Berchielli

    2011-07-01

    Full Text Available A laboratory culture of Ankistrodesmus gracilis algae was evaluated by studying the biology of the species and its chemical composition in a traditional medium (CHU12 and in two alternative culture media, NPK (20-5-20 and macrophyte (Eichhornia crassipes + NPK, in three different types of recipients (fiberglass, carboy and plastic bag. First peak in the growth curve of Ankistrodesmus gracilis occurred on the ninth day in macrophyte + NPK medium (74.16 x 105 cells mL-1 in a fiberglass recipient. However, highest density (p 12 (122.87 x 105 cells mL-1 in a plastic bag on the twelfth day. Cell density was over 70 x 105 cells mL-1 starting on the twelfth day. Growth rate of A. gracilis was similar (p > 0.05 in culture media in the three recipients. Protein and fiber were similar (p > 0.05 in the treatments, but lipids were higher (p -1 in NPK (p A. gracilis cultured in three types of recipients. Costs are low, occupying less space when cultured in plastic bags and in the laboratory.A laboratory culture of Ankistrodesmus gracilis algae was evaluated by studying the biology of the species and its chemical composition in a traditional medium (CHU12 and in two alternative culture media, NPK (20-5-20 and macrophyte (Eichhornia crassipes + NPK, in three different types of recipients (fiberglass, carboy and plastic bag. First peak in the growth curve of Ankistrodesmus gracilis occurred on the ninth day in macrophyte + NPK medium (74.16 x 105 cells mL-1 in a fiberglass recipient. However, highest density (p 12 (122.87 x 105 cells mL-1 in a plastic bag on the twelfth day. Cell density was over 70 x 105 cells mL-1 starting on the twelfth day. Growth rate of A. gracilis was similar (p > 0.05 in culture media in the three recipients. Protein and fiber were similar (p > 0.05 in the treatments, but lipids were higher (p -1 in NPK (p A. gracilis cultured in three types of recipients. Costs are low, occupying less space when cultured in plastic bags and in the

  9. 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.

  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. Quality-of-life improvement after free gracilis muscle transfer for smile restoration in patients with facial paralysis.

    Science.gov (United States)

    Lindsay, Robin W; Bhama, Prabhat; Hadlock, Tessa A

    2014-01-01

    Facial paralysis can contribute to disfigurement, psychological difficulties, and an inability to convey emotion via facial expression. In patients unable to perform a meaningful smile, free gracilis muscle transfer (FGMT) can often restore smile function. However, little is known about the impact on disease-specific quality of life. To determine quantitatively whether FGMT improves quality of life in patients with facial paralysis. Prospective evaluation of 154 FGMTs performed at a facial nerve center on 148 patients with facial paralysis. The Facial Clinimetric Evaluation (FaCE) survey and Facial Assessment by Computer Evaluation software (FACE-gram) were used to quantify quality-of-life improvement, oral commissure excursion, and symmetry with smile. Free gracilis muscle transfer. Change in FaCE score, oral commissure excursion, and symmetry with smile. There were 127 successful FGMTs on 124 patients and 14 failed procedures on 13 patients. Mean (SD) FaCE score increased significantly after successful FGMT (42.30 [15.9] vs 58.5 [17.60]; paired 2-tailed t test, P improved significantly in all subgroups (nonflaccid cohort, 37.8 [19.9] vs 52.9 [19.3]; P = .02; flaccid cohort, 43.1 [15.1] vs 59.6 [17.2]; P improved from a mean (SD) of 13.8 (7.46) to 4.88 (3.47) (P improvement in quality of life after FGMT in patients who could not recover a meaningful smile after facial nerve insult. Quality-of-life improvement was not statistically different between donor nerve groups or facial paralysis types.

  12. Biotechnological production of value-added carotenoids from microalgae: Emerging technology and prospects.

    Science.gov (United States)

    Wichuk, Kristine; Brynjólfsson, Sigurður; Fu, Weiqi

    2014-01-01

    We recently evaluated the relationship between abiotic environmental stresses and lutein biosynthesis in the green microalga Dunaliella salina and suggested a rational design of stress-driven adaptive evolution experiments for carotenoids production in microalgae. Here, we summarize our recent findings regarding the biotechnological production of carotenoids from microalgae and outline emerging technology in this field. Carotenoid metabolic pathways are characterized in several representative algal species as they pave the way for biotechnology development. The adaptive evolution strategy is highlighted in connection with enhanced growth rate and carotenoid metabolism. In addition, available genetic modification tools are described, with emphasis on model species. A brief discussion on the role of lights as limiting factors in carotenoid production in microalgae is also included. Overall, our analysis suggests that light-driven metabolism and the photosynthetic efficiency of microalgae in photobioreactors are the main bottlenecks in enhancing biotechnological potential of carotenoid production from microalgae.

  13. Transgene Expression in Microalgae-From Tools to Applications.

    Science.gov (United States)

    Doron, Lior; Segal, Na'ama; Shapira, Michal

    2016-01-01

    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 range of transformation

  14. 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

  15. 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.

  16. Euglenophyceae de ambientes lênticos na planície costeira do Rio Grande do Sul, Sul do Brasil: gêneros Euglena Ehr. e Lepocinclis Perty Euglenophyceae of lentic environments at the coastal plain of Rio Grande do Sul State, South of Brazil: genera Euglena Ehr. and Lepocinclis Perty

    Directory of Open Access Journals (Sweden)

    Sandra Maria Alves-da-Silva

    2006-06-01

    Full Text Available São apresentados 28 táxons específicos e infra-específicos dos gêneros Euglena Ehr. e Lepocinclis Perty como resultado do estudo do fitoplâncton e perifíton em ambientes lênticos (lagoas, açude e banhados da Lagoa do Casamento e ecossistemas associados (30º03'- 30º34'S e 50º25'- 50º47'W e ecossistemas próximos ao Butiazal de Tapes (30º23'- 30º38'S e 51º16'- 51º29'W na planície costeira do Rio Grande do Sul. As coletas abrangeram as estações de outono e primavera de 2003. As áreas úmidas (banhados associadas à Lagoa do Casamento na primavera de 2003 apresentaram maior riqueza específica destes dois gêneros. Lepocinclis salina Fritsch var. salina foi a espécie que se distinguiu quanto a distribuição por ter ocorrido em 41,2% do total de amostras analisadas. São novos registros para o estado do Rio Grande do Sul e país, L. playfairiana Defl. var. playfairiana e L. boseensis Xie, Qiu & Ling.Twenty eight specific and infra-specific taxa of the genera Euglena Ehr. and Lepocinclis Perty are presented as a result of phytoplankton and periphyton study in lentic systems next to Lagoa do Casamento (30º03'- 30º34'S and 50º25'- 50º47'W and Butiazal de Tapes (30º23'- 30º38'S and 51º16'- 51º29'W, coastal zone of Rio Grande do Sul State. Samples were collected in autumn and spring seasons in 2003. The swamps associated to Lagoa do Casamento in spring of 2003 presented more specific richness of these two genera. Lepocinclis salina Fritsch var. salina distinguished by its distribution, occuring in 41,2% of the analized samples. Two taxa are new records for the State and Brazil: L. playfairiana Defl. var. playfairiana and L. boseensis Xie, Qiu & Ling.

  17. Study of Euglenophyta in the Jacuí Delta State Park, Rio Grande do Sul, Brazil. 1. Euglena Ehr., Lepocinclis Perty Estudo de Euglenophyta no Parque Estadual Delta do Jacuí, Rio Grande do Sul, Brasil, 1. Euglena Ehr., Lepocinclis Perty

    Directory of Open Access Journals (Sweden)

    Sandra Maria Alves-da-Silva

    2004-03-01

    Full Text Available This paper is the result of the study of pigmented Euglenaceae performed within the area of the Jacuí Delta State Park, located between parallels 29º56' and 30º03'S and meridians 51º12'and 51º18'W, with qualitative samplings at 25 stations, distributed over 8 islands, 8 "sacos" (i.e. small bays, 4 river mouths, 2 stream mouths and 3 channels in December/1993 and January/1994, and from February/1998 to December/1999. One hundred and fifty taxa of the Euglenophyceae were identified in the area. Currently 23 specific and infraspecific taxa of genus Euglena and 12 taxa of Lepocinclis are presented. E. acus Ehr. var. acus, and L. salina Fritsch var. salina were the taxa best represented in the region since they occured in over 40% of the samples studied. E. bonettoi (Tell & Zaloc. Couté & Thérez., L. playfairiana Defl. var. striata Conf. and L. caudata (Cunha Conr. were recorded exclusively for South America; sixteen taxa identified have a cosmopolitan distribution. Ranges of some abiotic variables of the environments in which each taxon occurred in the study area are mentioned.Este trabalho é o resultado do estudo de Euglenaceae pigmentadas realizado na área do Parque Estadual Delta do Jacuí, localizado entre paralelos 29º56' e 30º03'S e os meridianos 51º12'e 51º18'W, com amostragens qualitativas em 25 estações de coletas distribuídas em 8 ilhas, 8 sacos, 6 desembocaduras de rios e 3 canais, em dezembro/1993 e janeiro/1994 e de fevereiro/1998 a dezembro/1999. Foram identificados na área cerca de 150 táxons de Euglenophyceae. São apresentados, neste trabalho, 23 táxons específicos e infra-específicos do gênero Euglena e 12 táxons de Lepocinclis. E. acus Ehr. var. acus e L. salina Fritsch var. salina foram os táxons melhor representados na área por ocorrerem em mais de 40% dos biótopos estudados. E. bonettoi (Tell & Zaloc. Couté & Thérez., L. playfairiana Defl. var. striata Conf. e L. caudata (Cunha Conr. foram

  18. 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.

  19. 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...

  20. 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.

  1. 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

    2015-01-01

    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 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. PMID:26473834

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. In vitro activity of essential oils of Lippia sidoides and Lippia gracilis and their major chemical components against Thielaviopsis paradoxa, causal agent of stem bleeding in coconut palms

    Directory of Open Access Journals (Sweden)

    Rejane Rodrigues da Costa e Carvalho

    2013-01-01

    Full Text Available Essential oils of Lippia sidoides, Lippia gracilis and their main chemical components were investigated for in vitro control of Thielaviopsis paradoxa. Mycelial growth and a number of pathogen conidia were inhibited by the essential oil of L. sidoides at all concentrations tested (0.2; 0.5; 1.0; 3.0 µL mL-1. L. sidoides oil contained 42.33% thymol and 4.56% carvacrol, while L. gracilis oil contained 10% thymol and 41.7% carvacrol. Mycelial growth and conidial production of T. paradoxa were completely inhibited by thymol at a 0.3 µL m-1 concentration. The results suggest that thymol could potentially be used for controlling coconut stem bleeding.

  7. 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)

  8. 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.

  9. Recent developments on biofuels production from microalgae and macroalgae

    DEFF Research Database (Denmark)

    Kumar, Kanhaiya; Ghosh, Supratim; Angelidaki, Irini

    2016-01-01

    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......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......, bringing together both microalgae and macroalgae on the same platform. It provides a brief overview on the mechanism of different biofuel production from algae. Factors affecting the biofuel process and the associated challenges have been highlighted alongwith analysis of techno-economic study available...

  10. Biorefinery of microalgae - opportunities and constraints for different production scenarios.

    Science.gov (United States)

    Hariskos, Ioanna; Posten, Clemens

    2014-06-01

    In order to design economically feasible production processes it is necessary, as part of the biorefinery concept, to valorize all constituents of the microalgal biomass. Such an approach requires appropriate biorefinery side-process strategies to be adapted to production of the primary product. These strategies are particularly valid for microalgae, since the composition and amount of residual biomass can vary significantly depending on cell stoichiometry and cultivation techniques. This review investigates opportunities and constraints for biorefinery concepts in production scenarios for four different products from microalgae with different market volumes, including high- and medium-value products, whole cells and biodiesel. Approaches to close material and energy balances, as well as to adapt the biorefinery according to biological potential, process routes, and market needs are presented, which will further contribute to making the biorefinery concept a success. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Anisotropic transport of microalgae Chlorella vulgaris in microfluidic channel

    International Nuclear Information System (INIS)

    Ishak, Nur Izzati; Muniandy, S V; Periasamy, Vengadesh; Ng, Fong-Lee; Phang, Siew-Moi

    2017-01-01

    In this work, we study the regional dependence of transport behavior of microalgae Chlorella vulgaris inside microfluidic channel on applied fluid flow rate. The microalgae are treated as spherical naturally buoyant particles. Deviation from the normal diffusion or Brownian transport is characterized based on the scaling behavior of the mean square displacement (MSD) of the particle trajectories by resolving the displacements in the streamwise (flow) and perpendicular directions. The channel is divided into three different flow regions, namely center region of the channel and two near-wall boundaries and the particle motions are analyzed at different flow rates. We use the scaled Brownian motion to model the transitional characteristics in the scaling behavior of the MSDs. We find that there exist anisotropic anomalous transports in all the three flow regions with mixed sub-diffusive, normal and super-diffusive behavior in both longitudinal and transverse directions. (paper)

  12. Improving biogas production from microalgae by enzymatic pretreatment.

    Science.gov (United States)

    Passos, Fabiana; Hom-Diaz, Andrea; Blanquez, Paqui; Vicent, Teresa; Ferrer, Ivet

    2016-01-01

    In this study, enzymatic pretreatment of microalgal biomass was investigated under different conditions and evaluated using biochemical methane potential (BMP) tests. Cellulase, glucohydrolase and an enzyme mix composed of cellulase, glucohydrolase and xylanase were selected based on the microalgae cell wall composition (cellulose, hemicellulose, pectin and glycoprotein). All of them increased organic matter solubilisation, obtaining high values already after 6h of pretreatment with an enzyme dose of 1% for cellulase and the enzyme mix. BMP tests with pretreated microalgae showed a methane yield increase of 8 and 15% for cellulase and the enzyme mix, respectively. Prospective research should evaluate enzymatic pretreatments in continuous anaerobic reactors so as to estimate the energy balance and economic cost of the process. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Fungitoxicidade dos extratos vegetais e do óleo essencial de Lippia gracilis Schauer sobre o fungo Monosporascus cannonballus Pollack e Uecker

    Directory of Open Access Journals (Sweden)

    Luciana Cristina Borges Fernandes

    2015-06-01

    Full Text Available Alecrim da Chapada (Lippia gracilis Schauer é considerada uma planta rica em óleo essencial e possui atividade antimicrobiana comprovada, devido aos monoterpenos fenólicos carvacrol e timol. O objetivo deste trabalho foi avaliar o efeito in vitro do óleo essencial e dos extratos etanólicos de raízes e folhas de L. gracilis no controle do fungo Monosporasccus cannonballus, causador do colapso do meloeiro. O extratos foram testados nas concentrações de 2500, 5000 e 7500 ppm e o óleo essencial de L. gracilis foi avaliado nas concentrações 255, 340 e 425 ppm tendo também um controle positivo com o fungicida comercial Captan(r e um negativo apenas com meio BDA (batata, dextrose, ágar. Discos de micélio com 3 mm de diâmetro foram inoculados no centro de placas de Petri e as medições do crescimento micelial do fungo foram realizadas 48 horas após a montagem do experimento. Verificou-se que o óleo essencial de L. gracilis nas três concentrações testadas foi eficiente para o controle do fungo, com percentuais de inibição de 100%, em comparação ao tratamento com o controle negativo (0% que não apresentou inibição. O extrato radicular, nas concentrações de 5000 e 7500 ppm e o extrato foliar na concentração de 7500 ppm também proporcionaram um percentual de inibição de 100%.

  14. 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 ...

  15. A Novel Enclosed Online Control System for Microalgae Production

    Directory of Open Access Journals (Sweden)

    Bin Li

    2014-03-01

    Full Text Available Microalgae are single celled microscopic organisms which, like plants, convert solar energy into bio-energy through photosynthesis. They can be used to produce a variety of bio-based products, such as bio-food and biodiesel. Large scale algae production can be achieved in open or closed systems. An enclosed online microalgae control production system is presented in this paper. The designed system is composed of a reactor which is placed inside a box with light reflecting surface. Lighting system, CO2 supply, heating, as well as online cell mass monitoring via spectrophotometer, were integrated. The online monitoring of cell mass concentration is coupled to two pumps which remove a certain amount of cell suspension, and take fresh media as an alternative. Also, a LabView program was developed to collect data from a spectrophotometer and processed in a computer. Considering the limited experimental conditions and the pollution possibility for its high productivity if liquid is not properly disposed, food color was used to test the designed novel system in this paper. The results showed that, the system could detect a change in absorption over time with periodic sampling for every 4.8 minutes. When absorption value reach a pre-set gate, pump1 immediately starts to pump out a certain amount of solution?then pump2 starts to pump in fresh media according to the calculated time. The concentration could be controlled below the threshold value. From the continuous test using food color, the designed system showed good stability and controlling accuracy. It provides a good reference for the following microalgae testing experiment in future. Considering the applications of microalgae in agriculture, this research also provides resources for bio-fertilizer.

  16. "Rational" management of dichlorophenols biodegradation by the microalga Scenedesmus obliquus.

    Science.gov (United States)

    Papazi, Aikaterini; Kotzabasis, Kiriakos

    2013-01-01

    The microalga Scenedesmus obliquus exhibited the ability to biodegrade dichlorophenols (dcps) under specific autotrophic and mixotrophic conditions. According to their biodegradability, the dichlorophenols used can be separated into three distinct groups. Group I (2,4-dcp and 2,6 dcp - no meta-substitution) consisted of quite easily degraded dichlorophenols, since both chloride substituents are in less energetically demanding positions. Group II (2,3-dcp, 2,5-dcp and 3,4-dcp - one meta-chloride) was less susceptible to biodegradation, since one of the two substituents, the meta one, required higher energy for C-Cl-bond cleavage. Group III (3,5-dcp - two meta-chlorides) could not be biodegraded, since both chlorides possessed the most energy demanding positions. In general, when the dcp-toxicity exceeded a certain threshold, the microalga increased the energy offered for biodegradation and decreased the energy invested for biomass production. As a result, the biodegradation per cell volume of group II (higher toxicity) was higher, than group I (lower toxicity) and the biodegradation of dichlorophenols (higher toxicity) was higher than the corresponding monochlorophenols (lower toxicity). The participation of the photosynthetic apparatus and the respiratory mechanism of microalga to biodegrade the group I and the group II, highlighted different bioenergetic strategies for optimal management of the balance between dcp-toxicity, dcp-biodegradability and culture growth. Additionally, we took into consideration the possibility that the intermediates of each dcp-biodegradation pathway could influence differently the whole biodegradation procedures. For this reason, we tested all possible combinations of phenolic intermediates to check cometabolic interactions. The present contribution bring out the possibility of microalgae to operate as "smart" bioenergetic "machines", that have the ability to continuously "calculate" the energy reserves and "use" the most energetically

  17. Spectral optical properties of selected photosynthetic microalgae producing biofuels

    International Nuclear Information System (INIS)

    Lee, Euntaek; Heng, Ri-Liang; Pilon, Laurent

    2013-01-01

    This paper presents the spectral complex index of refraction of biofuel producing photosynthetic microalgae between 400 and 750 nm. They were retrieved from their experimentally measured average absorption and scattering cross-sections. The microalgae were treated as homogeneous polydisperse spheres with equivalent diameter such that their surface area was identical to that of their actual spheroidal shape. An inverse method was developed combining Lorentz–Mie theory as the forward method and genetic algorithm. The unicellular green algae Chlamydomonas reinhardtii strain CC125 and its truncated chlorophyll antenna transformants tla1, tlaX, and tla1-CW + as well as Botryococcus braunii, Chlorella sp., and Chlorococcum littorale were investigated. These species were selected for their ability to produce either hydrogen gas or lipids for liquid fuel production. Their retrieved real and imaginary parts of the complex index of refraction were continuous functions of wavelength with absorption peaks corresponding to those of in vivo Chlorophylls a and b. The T-matrix method was also found to accurately predict the experimental measurements by treating the microalgae as axisymmetric spheroids with the experimentally measured major and minor diameter distributions and the retrieved spectral complex index of refraction. Finally, pigment mass fractions were also estimated from the retrieved absorption index. The method and/or the reported optical properties can be used in various applications from ocean remote sensing, carbon cycle study, as well as photobiological carbon dioxide mitigation and biofuel production. -- Highlights: ► Retrieval of optical properties from average absorption and scattering cross-sections. ► Inverse method based on Lorentz–Mie theory and genetic algorithm. ► Refraction and absorption indices of selected microalgae between 400 and 750 nm. ► Determination of pigment concentrations from absorption index. ► Good agreement between T

  18. 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.

  19. 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.

  20. 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.

  1. Prospects of biodiesel production from microalgae in India

    Energy Technology Data Exchange (ETDEWEB)

    Khan, Shakeel A.; Hussain, Mir Z.; Prasad, S. [Division of Environmental Sciences, Indian Agricultural Research Institute, New Delhi 110012 (India); Rashmi; Banerjee, U.C. [Department of Pharmaceutical Technology (Biotechnology), National Institute of Pharmaceutical and Education Research (NIPER), Sector 67, Phase X, S.A.S. Nagar, Mohali 160062, Punjab (India)

    2009-12-15

    Energy is essential and vital for development, and the global economy literally runs on energy. The use of fossil fuels as energy is now widely accepted as unsustainable due to depleting resources and also due to the accumulation of greenhouse gases in the environment. Renewable and carbon neutral biodiesel are necessary for environmental and economic sustainability. Biodiesel demand is constantly increasing as the reservoir of fossil fuel are depleting. Unfortunately biodiesel produced from oil crop, waste cooking oil and animal fats are not able to replace fossil fuel. The viability of the first generation biofuels production is however questionable because of the conflict with food supply. Production of biodiesel using microalgae biomass appears to be a viable alternative. The oil productivity of many microalgae exceeds the best producing oil crops. Microalgae are photosynthetic microorganisms which convert sunlight, water and CO{sub 2} to sugars, from which macromolecules, such as lipids and triacylglycerols (TAGs) can be obtained. These TAGs are the promising and sustainable feedstock for biodiesel production. Microalgal biorefinery approach can be used to reduce the cost of making microalgal biodiesel. Microalgal-based carbon sequestration technologies cover the cost of carbon capture and sequestration. The present paper is an attempt to review the potential of microalgal biodiesel in comparison to the agricultural crops and its prospects in India. (author)

  2. 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.

  3. 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).

  4. 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

  5. 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.

  6. 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.

  7. 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

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. The impact of Manjil and Tarik dams (Sefidroud River, southern Caspian Sea basin on morphological traits of Siah Mahi Capoeta gracilis (Pisces: Cyprinidae

    Directory of Open Access Journals (Sweden)

    Adeleh Heidari

    2013-08-01

    Full Text Available It has been postulated that the building of the Manjil and Tarik dams on Sefidroud River has led to the body shape variation of Capoeta gracilis in up- and downstream populations due to the isolation. In this study, Geometric morphometric approach was used to explore body shape variations of Capoeta gracilis populations in up- and downstream Manjil and Tarik dams in Sefidroud River from south of the Caspian Sea basin. The shape of 90 individuals from three sampling sites was extracted by recording the 2-D coordinates of 13 landmark points. PCA, CVA, DFA and CA analysis were used to examine shape differences among the populations. The significant differences were found among the shape of the populations and these differences were observed in the snout, the caudal peduncle and head. The present study indicated the body shape differences in the populations of Capoeta gracilis in the Sefidroud River across the Manjil and Tarik dams, probably due to the dam construction showing anthropogenic transformation of rivers influences body shape in an aquatic organism.

  13. Optic chiasm in the species of order Clupeiformes, family Clupeidae: optic chiasm of Spratelloides gracilis shows an opposite laterality to that of Etrumeus teres.

    Science.gov (United States)

    Mogi, Kazue; Misawa, Kazuya; Utsunomiya, Kentaro; Kawada, Yuta; Yamazaki, Toshihisa; Takeuchi, Shigeo; Toyoizumi, Ryuji

    2009-09-01

    In most teleost fishes, the optic nerves decussate completely as they project to the mesencephalic region. Examination of the decussation pattern of 25 species from 11 different orders in Pisces revealed that each species shows a specific chiasmic type. In 11 species out of the 25, laterality of the chiasmic pattern was not determined; in half of the individuals examined, the left optic nerve ran dorsally to the right optic nerve, while in the other half, the right optic nerve was dorsal. In eight other species the optic nerves from both eyes branched into several bundles at the chiasmic point, and intercalated to form a complicated decussation pattern. In the present study we report our findings that Spratelloides gracilis, of the order Clupeiformes, family Clupeidae, shows a particular laterality of decussation: the left optic nerve ran dorsally to the right (n=200/202). In contrast, Etrumeus teres, of the same order and family, had a strong preference of the opposite (complementary) chiasmic pattern to that of S. gracilis (n=59/59), revealing that these two species display opposite left-right optic chiasm patterning. As far as we investigated, other species of Clupeiformes have not shown left-right preference in the decussation pattern. We conclude that the opposite laterality of the optic chiasms of these two closely related species, S. gracilis and E. teres, enables investigation of species-specific laterality in fishes of symmetric shapes.

  14. Ciclo reproductivo de Liolaemus gracilis Bell, 1843 (Iguanidae: Tropidurinae en las dunas costeras de Buenos Aires, Argentina

    Directory of Open Access Journals (Sweden)

    Vega, Laura Estela

    2005-02-01

    Full Text Available Estudiamos la fenología y edad de madurez reproductiva y el tamaño y la frecuencia de la puesta de una población de Liolaemus gracilis de las dunas costeras de Buenos Aires, Argentina. Examinamos las gónadas de 93 ejemplares coleccionados mensualmente a lo largo de un año en la localidad de Mar del Sur (provincia de Buenos Aires y medimos 11 caracteres morfométricos en 39 adultos en búsqueda de dimorfismo sexual. Las hembras se consideraron maduras si poseían folículos yemados mayores a 2 mm, o huevos oviductales, u oviductos claramente distendidos. En los machos los indicadores de madurez sexual fueron la presencia de testículos agrandados y el estado convoluto de los epidídimos, midiéndose el ancho y largo del testículo izquierdo en cada uno. L. gracilis exhibió un patrón reproductivo estacional con características del tipo parcial de otoño. El tamaño medio de las hembras en actividad reproductiva fue de 48,9 mm ± 3,5 (largo hocico-cloaca (n = 19 y la menor madura sexualmente midió 43,8 mm. El tamaño de la puesta varió de 4 a 6 huevos ( X = 4,75 ± 0,95, n = 4. El macho de menor tamaño con testículos agrandados midió 40,5 mm. (largo hocico-cloaca. Tanto los machos como las hembras estuvieron reproductivamente activos desde comienzos del otoño hasta comienzos del verano. Las hembras producirían una puesta por año entre fines de la primavera y comienzos del verano y las crías nacerían a mediados de esta estación. Encontramos dimorfismo sexual en la mayor distancia entre los miembros anteriores y posteriores de las hembras y en la mayor longitud de la cabeza, tibio-fíbula y pie de los machos. We studied the reproductive phenology, size at maturity, frequency and clutch size of a lizard population of Liolaemus gracilis from coastal sand dunes of Buenos Aires, Argentina. We examined 93 specimens collected monthly throughout a year in the locality of Mar del Sur (Buenos Aires province and measured 11 morphometric

  15. 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.

  16. HPLC-DAD analysis, antioxidant potential and anti-urease activity of Asparagus gracilis collected from District Islamabad.

    Science.gov (United States)

    Shah, Naseer Ali; Khan, Muhammad Rashid; Sattar, Saadia; Ahmad, Bushra; Mirza, Bushra

    2014-09-23

    Asparagus gracilis subspecie of Asparagus capitatus Baker, is described as food and medicine for various ailments. In this study we investigated, its phenolic constituents, in vitro antioxidant potential against various free radicals and anti-urease potential. Asparagus gracilis aerial parts collected from District Islamabad, Pakistan were extracted with crude methanol which was further fractionated into n-hexane, ethyl acetate, n-butanol and aqueous fraction. Total phenolic and flavonoid contents were estimated for extract and all the derived fractions. Diverse in vitro antioxidants assays such as DPPH, H2O2, •OH, ABTS, β-carotene bleaching assay, superoxide radical, lipid peroxidation, reducing power, and total antioxidant capacity were studied to assess scavenging potential. Antiurease activity of methanol extract and its derived fractions was also investigated. HPLC-DAD analysis of crude methanol extract was performed by using different phenolic standards. Ethyl acetate fraction expressed maximum content of flavonoids (240.6 ± 6.1 mg RE/g dry sample), phenolics (615 ± 13 mg GAE/g dry sample) and best antioxidant potential among different fractions of crude methanol extract. Hydrogen peroxide assay and hydroxyl, supeoxide, nitric oxide free radicals antioxidant assays as well as beta carotene assay showed significant correlation with flavonoid content while hydrogen peroxide, ABTS and lipid peroxidation assay displayed significant correlation with phenolic content. HPLC analysis showed the presence of important phenolics i.e. catechin (4.04 ± 0.02 μg/mg sample), caffeic acid (0.89 ± 0.003 μg/mg sample), rutin (24.58 ± 0.1 μg/mg sample), myricetin (1.13 ± 0.07 μg/mg sample) and quercetin (14.91 ± 0.09 μg/mg sample). Ethyl acetate fraction expressed lowest IC50 in antiurease activity. Correlation analysis of antiurease activity expressed significant correlation with flavonoids (P < 0.004) and phenolics (P < 0.02) proposing multipotent activity of

  17. Comparison of Oone-Stage Free Gracilis Muscle Flap With Two-Stage Method in Chronic Facial Palsy

    Directory of Open Access Journals (Sweden)

    J Ghaffari

    2007-08-01

    Full Text Available Background:Rehabilitation of facial paralysis is one of the greatest challenges faced by reconstructive surgeons today. The traditional method for treatment of patients with facial palsy is the two-stage free gracilis flap which has a long latency period of between the two stages of surgery.Methods: In this paper, we prospectively compared the results of the one-stage gracilis flap method with the two -stage technique.Results:Out of 41 patients with facial palsy refered to Hazrat-e-Fatemeh Hospital 31 were selected from whom 22 underwent two- stage and 9 one-stage method treatment. The two groups were identical according to age,sex,intensity of illness, duration, and chronicity of illness. Mean duration of follow up was 37 months. There was no significant relation between the two groups regarding the symmetry of face in repose, smiling, whistling and nasolabial folds. Frequency of complications was equal in both groups. The postoperative surgeons and patients' satisfaction were equal in both groups. There was no significant difference between the mean excursion of muscle flap in one-stage (9.8 mm and two-stage groups (8.9 mm. The ratio of contraction of the affected side compared to the normal side was similar in both groups. The mean time of the initial contraction of the muscle flap in the one-stage group (5.5 months had a significant difference (P=0.001 with the two-stage one (6.5 months.The study revealed a highly significant difference (P=0.0001 between the mean waiting period from the first operation to the beginning of muscle contraction in one-stage(5.5 monthsand two-stage groups(17.1 months.Conclusion:It seems that the results and complication of the two methods are the same,but the one-stage method requires less time for facial reanimation,and is costeffective because it saves time and decreases hospitalization costs.

  18. 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.

  19. 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....

  20. Techno-economic assessment of micro-algae as feedstock for renewable bio-energy production

    NARCIS (Netherlands)

    Jonker, J.G.G.; Faaij, A.P.C.|info:eu-repo/dai/nl/10685903X

    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

  1. 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

  2. Mild disintegration of the green microalgae Chlorella vulgaris using bead milling

    NARCIS (Netherlands)

    Postma, P.R.; Miron, T.L.; Olivieri, G.; Barbosa, M.J.; Wijffels, R.H.; Eppink, M.H.M.

    2015-01-01

    In this work, the mild disintegration of the microalgae Chlorella vulgaris for the release of intracellular products has been studied. By means of bead milling the microalgae suspensions were successfully disintegrated at different biomass concentrations (25–145 gDW kg-1) over a range of agitator

  3. 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

  4. 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.

  5. The impact of nitrogen starvation on the dynamics of triacylglycerol accumulation in nine microalgae strains

    NARCIS (Netherlands)

    Breuer, G.; Lamers, P.P.; Martens, D.E.; Draaisma, R.B.; Wijffels, R.H.

    2012-01-01

    Microalgae-derived lipids are an alternative to vegetable and fossil oils, but lipid content and quality vary among microalgae strains. Selection of a suitable strain for lipid production is therefore of paramount importance. Based on published results for 96 species, nine strains were selected to

  6. Cranial pneumatization and auditory perceptions of the oviraptorid dinosaur Conchoraptor gracilis (Theropoda, Maniraptora) from the Late Cretaceous of Mongolia

    Science.gov (United States)

    Ramanah, D.; Raghunath, S.; Mee, D. J.; Rösgen, T.; Jacobs, P. A.

    2007-09-01

    The distribution of air-filled structures in the craniofacial and neurocranial bones of the oviraptorid ZPAL MgD-I/95, discovered at the Hermiin Tsav locality, Mongolia, is restored. Based on the complete obliteration of most of the cranial sutures, the specimen is identified as an adult individual of Conchoraptor gracilis Barsbold 1986. Except for the orbitosphenoids and epipterygoids, the preserved bones of the neurocranium are hollow. Three types of tympanic recess are present in Conchoraptor, a characteristic shared with troodontids, dromaeosaurids, and avian theropods. The contralateral middle ear cavities are interconnected by the supraencephalic pathway that passes through the dorsal tympanic recesses, the posterodorsal prootic sinuses and the parietal sinus. The spatial arrangements of the middle ear cavity and a derived neurocranial pneumatic system in Conchoraptor indicate enhancements of acoustic perception in the lower-frequency registers and of auditory directionality. We further speculate that this improvement of binaural hearing could be explained as an adaptation required for accurate detection of prey and/or predators under conditions of low illumination. The other potentially pneumatic structures of the Conchoraptor cranium include (1) recessus-like irregularities on the dorsal surface of the nasal and frontal bones (a putative oviraptorid synapomorphy; pos); (2) a subotic recess; (3) a sub-condylar recess; and (4) a posterior condylar recess (pos).

  7. Effects of chronic exposure in populations of Koeleria gracilis Pers. from the Semipalatinsk nuclear test site, Kazakhstan.

    Science.gov (United States)

    Geras'kin, S A; Oudalova, A A; Dikarev, V G; Dikareva, N S; Mozolin, E M; Hinton, T; Spiridonov, S I; Copplestone, D; Garnier-Laplace, J

    2012-02-01

    Morphological and cytogenetic abnormalities were examined in crested hairgrass (Koeleria gracilis Pers.) populations inhabiting the Semipalatinsk nuclear test site (STS), Kazakhstan. Sampling of biological material and soil was carried out during 3 years (2005-2007) at 4 sites within the STS. Activity concentrations of 10 radionuclides and 8 heavy metals content in soils were measured. Doses absorbed by plants were estimated and varied, depending on the plot, from 4 up to 265 mGy/y. The frequency of cytogenetic alterations in apical meristem of germinated seeds from the highly contaminated plot significantly exceeded the level observed at other plots with lower levels of radioactive contamination during all three years of the study. A significant excess of chromosome aberrations, typical for radiation exposure, as well as a dependence of the frequency of these types of mutations on dose absorbed by plants were revealed. The results indicate the role radioactive contamination plays in the occurrence of cytogenetic effects. However, no radiation-dependent morphological alterations were detected in the progeny of the exposed populations. Given that the crested hairgrass populations have occupied the radioactively contaminated plots for some 50 years, adaptation to the radiation stress was not evident. The findings obtained were in agreement with the benchmark values proposed in the FASSET and ERICA projects to restrict radiation impacts on biota. Copyright © 2011 Elsevier Ltd. All rights reserved.

  8. Chemical mechanism of D-amino acid oxidase from Rhodotorula gracilis: pH dependence of kinetic parameters.

    Science.gov (United States)

    Ramón, F; Castillón, M; De La Mata, I; Acebal, C

    1998-01-01

    The variation of kinetic parameters of d-amino acid oxidase from Rhodotorula gracilis with pH was used to gain information about the chemical mechanism of the oxidation of D-amino acids catalysed by this flavoenzyme. d-Alanine was the substrate used. The pH dependence of Vmax and Vmax/Km for alanine as substrate showed that a group with a pK value of 6.26-7.95 (pK1) must be unprotonated and a group with a pK of 10.8-9.90 (pK2) must be protonated for activity. The lower pK value corresponded to a group on the enzyme involved in catalysis and whose protonation state was not important for binding. The higher pK value was assumed to be the amino group of the substrate. Profiles of pKi for D-aspartate as competitive inhibitor showed that binding is prevented when a group on the enzyme with a pK value of 8.4 becomes unprotonated; this basic group was not detected in Vmax/Km profiles suggesting its involvement in binding of the beta-carboxylic group of the inhibitor. PMID:9461524

  9. 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.

  10. 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.

  11. 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.

  12. 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

  13. 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.

  14. 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

  15. 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.

  16. 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.

  17. 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.

  18. 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

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. Removal of metal from acid mine drainage using a hybrid system including a pipes inserted microalgae reactor.

    Science.gov (United States)

    Park, Young-Tae; Lee, Hongkyun; Yun, Hyun-Shik; Song, Kyung-Guen; Yeom, Sung-Ho; Choi, Jaeyoung

    2013-12-01

    In this study, the microalgae culture system to combined active treatment system and pipe inserted microalgae reactor (PIMR) was investigated. After pretreated AMD in active treatment system, the effluent load to PIMR in order to Nephroselmis sp. KGE 8 culture. In experiment, effect of iron on growth and lipid accumulation in microalgae were inspected. The 2nd pretreatment effluent was economic feasibility of microalgae culture and lipid accumulation. The growth kinetics of the microalgae are modeled using logistic growth model and the model is primarily parameterized from data obtained through an experimental study where PIMR were dosed with BBM, BBM added 10 mg L(-1) iron and 2nd pretreatment effluent. Moreover, the continuous of microalgae culture in PIMR can be available. Overall, this study indicated that the use of pretreated AMD is a viable method for culture microalgae and lipid accumulation. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Bacterial Influence on Alkenones in Live Microalgae1

    Science.gov (United States)

    Segev, Einat; Castañeda, Isla S.; Sikes, Elisabeth L.; Vlamakis, Hera; Kolter, Roberto

    2015-01-01

    The microalga Emiliania huxleyi produces alkenone lipids which are important proxies for estimating past sea surface temperatures. Field calibrations of this proxy are robust but highly variable results are obtained in culture. Here we present results suggesting that algal-bacterial interactions may be responsible for some of this variability. Co-cultures of E. huxleyi and the bacterium Phaeobacter inhibens resulted in a 2.5-fold decrease in algal alkenone-containing lipid bodies. In addition levels of unsaturated alkenones increase in co-cultures. These changes result in an increase in the reconstructed growth temperature of up to 2°C relative to axenic algal cultures. PMID:26987094

  5. Potency of Microalgae as Biodiesel Source in Indonesia

    OpenAIRE

    Hadiyanto, H; Widayat, W; Cahyo Kumoro, Andri

    2012-01-01

    Within 20 years, Indonesia should find another energy alternative to substitute current 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, however the utilization of microalgae as biofuel production is still limited. The biodiesel from current sources (Jatropha, palm oil, and sorghum) is still not able to cover all the needs if the fossil oil cannot be explored anymor...

  6. 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.

  7. 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.

  8. 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.

  9. [Progress in microalgae culture system for biodiesel combined with reducing carbon dioxide emission].

    Science.gov (United States)

    Su, Hongyang; Zhou, Xuefei; Xia, Xuefen; Sun, Zhen; Zhang, Yalei

    2011-09-01

    Wastewater resources, CO2 emission reduction and microalgae biodiesel are considered as current frontier fields of energy and environmental researches. In this paper, we reviewed the progress in system of microalgae culture for biodiesel production by wastewater and stack gas. Multiple factors including microalgal species, nutrition, culture methods and photobioreactor, which were crucial to the cultivation of microalgae for biodiesel production, were discussed in detail. A valuable culture system of microalgae for biodiesel production or other high value products combined with the treatment of wastewater by microalgae was put forward through the optimizations of algal species and culture technology. The culture system coupled with the treatment of wastewater, the reduction of CO2 emission with the cultivation of microalgae for biodiesel production will reduce the production cost of microalgal biofuel production and the treatment cost of wastewater simultaneously. Therefore, it would be a promising technology with important environmental value, social value and economic value to combine the treatment of wastewater with the cultivation of microalgae for biodiesel production.

  10. Eupafolin and Ethyl Acetate Fraction of Kalanchoe gracilis Stem Extract Show Potent Antiviral Activities against Enterovirus 71 and Coxsackievirus A16

    Science.gov (United States)

    Wang, Ching-Ying; Huang, Shun-Chueh; Lai, Zhen-Rung; Ho, Yu-Ling; Jou, Yu-Jen; Kung, Szu-Hao; Zhang, Yongjun; Chang, Yuan-Shiun; Lin, Cheng-Wen

    2013-01-01

    Enterovirus 71 (EV71) and coxsackievirus A16 (CoxA16) are main pathogens of hand-foot-and-mouth disease, occasionally causing aseptic meningitis and encephalitis in tropical and subtropical regions. Kalanchoe gracilis, Da-Huan-Hun, is a Chinese folk medicine for treating pain and inflammation, exhibiting antioxidant and anti-inflammatory activities. Our prior report (2012) cited K. gracilis leaf extract as moderately active against EV71 and CoxA16. This study further rates antienteroviral potential of K. gracilis stem (KGS) extract to identify potent antiviral fractions and components. The extract moderately inhibits viral cytopathicity and virus yield, as well as in vitro replication of EV71 (IC50 = 75.18 μg/mL) and CoxA16 (IC50 = 81.41 μg/mL). Ethyl acetate (EA) fraction of KGS extract showed greater antiviral activity than that of n-butanol or aqueous fraction: IC50 values of 4.21 μg/mL against EV71 and 9.08 μg/mL against CoxA16. HPLC analysis, UV-Vis absorption spectroscopy, and plaque reduction assay indicate that eupafolin is a vital component of EA fraction showing potent activity against EV71 (IC50 = 1.39 μM) and CoxA16 (IC50 = 5.24 μM). Eupafolin specifically lessened virus-induced upregulation of IL-6 and RANTES by inhibiting virus-induced ERK1/2, AP-1, and STAT3 signals. Anti-enteroviral potency of KGS EA fraction and eupafolin shows the clinical potential against EV71 and CoxA16 infection. PMID:24078828

  11. Eupafolin and Ethyl Acetate Fraction of Kalanchoe gracilis Stem Extract Show Potent Antiviral Activities against Enterovirus 71 and Coxsackievirus A16

    Directory of Open Access Journals (Sweden)

    Ching-Ying Wang

    2013-01-01

    Full Text Available Enterovirus 71 (EV71 and coxsackievirus A16 (CoxA16 are main pathogens of hand-foot-and-mouth disease, occasionally causing aseptic meningitis and encephalitis in tropical and subtropical regions. Kalanchoe gracilis, Da-Huan-Hun, is a Chinese folk medicine for treating pain and inflammation, exhibiting antioxidant and anti-inflammatory activities. Our prior report (2012 cited K. gracilis leaf extract as moderately active against EV71 and CoxA16. This study further rates antienteroviral potential of K. gracilis stem (KGS extract to identify potent antiviral fractions and components. The extract moderately inhibits viral cytopathicity and virus yield, as well as in vitro replication of EV71 (IC50 = 75.18 μg/mL and CoxA16 (IC50 = 81.41 μg/mL. Ethyl acetate (EA fraction of KGS extract showed greater antiviral activity than that of n-butanol or aqueous fraction: IC50 values of 4.21 μg/mL against EV71 and 9.08 μg/mL against CoxA16. HPLC analysis, UV-Vis absorption spectroscopy, and plaque reduction assay indicate that eupafolin is a vital component of EA fraction showing potent activity against EV71 (IC50 = 1.39 μM and CoxA16 (IC50 = 5.24 μM. Eupafolin specifically lessened virus-induced upregulation of IL-6 and RANTES by inhibiting virus-induced ERK1/2, AP-1, and STAT3 signals. Anti-enteroviral potency of KGS EA fraction and eupafolin shows the clinical potential against EV71 and CoxA16 infection.

  12. Reconstruction of the pelvic floor and the vagina after total pelvic exenteration using the transverse musculocutaneous gracilis flap.

    Science.gov (United States)

    Kaartinen, Ilkka S; Vuento, Maarit H; Hyöty, Marja K; Kallio, Jukka; Kuokkanen, Hannu O

    2015-01-01

    Total pelvic exenteration (TPE) is a rare operation in which the pelvic contents are removed entirely. Several options for pelvic floor and vaginal reconstruction have been described including transverse rectus abdominis musculocutaneous (TRAM) or deep inferior epigastric perforator (DIEP) flaps. The transverse musculocutaneous gracilis (TMG) flap has been introduced for breast reconstruction as a free flap. We adopted the pedicled TMG flap for reconstructions after TPE. To the best of our knowledge, this is the first report of this method in the literature. Between November 2011 and February 2014, 12 patients underwent TPE and reconstruction with unilateral (six patients) or bilateral (six patients) pedicled TMG flaps. Five patients underwent vaginal reconstruction with bilateral TMG flaps. We describe the operative procedure and the outcome of the operation in these patients. The total mean operative times for TPE with or without vaginal reconstruction were 467 ± 12 and 386 ± 59 min, respectively. The TMG flaps had enough vascular tissue and mobility for reconstructing the TPE defects. There was distal edge necrosis in one out of 18 flaps, while the rest survived completely. During the follow-up, complete wound healing with no signs of weakening of the pelvic floor was observed in all cases. Soft-tissue reconstructions are needed to reduce complications associated with TPE, to secure the pelvic floor and to reconstruct the vagina in select patients. The TMG flap is a logical flap choice that does not lead to functional deficits, complicate the abdominal ostomies or weaken the abdominal wall. It reduces the length of operation compared to that of abdominal flaps. IV, therapeutic. Copyright © 2014 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

  13. Effects of chronic exposure in populations of Koeleria gracilis Pers. from the Semipalatinsk nuclear test site, Kazakhstan

    International Nuclear Information System (INIS)

    Geras'kin, S.A.; Oudalova, A.A.; Dikarev, V.G.; Dikareva, N.S.; Mozolin, E.M.; Hinton, T.; Spiridonov, S.I.; Copplestone, D.; Garnier-Laplace, J.

    2012-01-01

    Morphological and cytogenetic abnormalities were examined in crested hairgrass (Koeleria gracilis Pers.) populations inhabiting the Semipalatinsk nuclear test site (STS), Kazakhstan. Sampling of biological material and soil was carried out during 3 years (2005–2007) at 4 sites within the STS. Activity concentrations of 10 radionuclides and 8 heavy metals content in soils were measured. Doses absorbed by plants were estimated and varied, depending on the plot, from 4 up to 265 mGy/y. The frequency of cytogenetic alterations in apical meristem of germinated seeds from the highly contaminated plot significantly exceeded the level observed at other plots with lower levels of radioactive contamination during all three years of the study. A significant excess of chromosome aberrations, typical for radiation exposure, as well as a dependence of the frequency of these types of mutations on dose absorbed by plants were revealed. The results indicate the role radioactive contamination plays in the occurrence of cytogenetic effects. However, no radiation-dependent morphological alterations were detected in the progeny of the exposed populations. Given that the crested hairgrass populations have occupied the radioactively contaminated plots for some 50 years, adaptation to the radiation stress was not evident. The findings obtained were in agreement with the benchmark values proposed in the FASSET and ERICA projects to restrict radiation impacts on biota. - Highlights: ► Morphological and cytogenetic abnormalities were examined in plants from the STS. ► Annual doses absorbed by plants varied from 4 up to 265 mGy. ► Cytogenetic alterations in plants from the explosions epicenter exceeded the control. ► No radiation-dependent morphological alterations were detected in the progeny. ► Radio-adaptation in plant populations in 50 years of chronic exposure was not evident.

  14. Analgesic and anti-inflammatory activities of the methanol extract of Kalanchoe gracilis (L.) DC stem in mice.

    Science.gov (United States)

    Lai, Zhen-Rung; Peng, Wen-Huang; Ho, Yu-Ling; Huang, Shun-Chieh; Huang, Tai-Hung; Lai, Shang-Chih; Ku, Yoe-Ray; Tsai, Jen-Chieh; Wang, Ching-Ying; Chang, Yuan-Shiun

    2010-01-01

    In this study, we evaluated the analgesic effect of the methanol extract of Kalanchoe gracilis (MKGS) stem in animal models by inducing writhing response with acetic acid and conducting formalin test. The anti-inflammatory effect of MKGS was also estimated on mice with lambda-carrageenan induced paw edema model. In order to investigate the anti-inflammatory mechanism of MKGS, we analyzed the activities of glutathione peroxidase (GPx) and glutathione reductase (GRx) in the liver, and the levels of interleukin-1beta (IL-1beta), tumor necrosis factor (TNF-alpha), malondialdehyde (MDA) and nitric oxide (NO) in the edema paw tissue. In the analgesic tests, MKGS (0.5 and 1.0 g/kg) decreased both the acetic acid-induced writhing response and the licking time in the late phase of the formalin test. In the anti-inflammatory test, MKGS (0.1, 0.5 and 1.0 g/kg) decreased paw edema at the third, fourth, fifth and sixth hours after lambda-carrageenan had been administrated. Furthermore, MKGS increased the activities of SOD and GRx in liver tissues and decreased MDA level in the edema paws three hours after lambda-carrageenan was injected. MKGS also affected the levels of IL-1beta, TNF-alpha and NO induced by lambda-carrageenan. All these results suggested that MKGS possessed analgesic and anti-inflammatory effects. The anti-inflammatory mechanism of MKGS might be related to the lowering of MDA level in the edema paw via increasing the activities of superoxide dismutase (SOD) and GRx in the liver, as well as the decreases in the levels of TNF-alpha and NO, and the production of IL-1beta in inflamed tissues.

  15. 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.)

  16. 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.

  17. 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.

  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 251C 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. Lipid Extraction Methods from Microalgae: A Comprehensive Review

    Energy Technology Data Exchange (ETDEWEB)

    Ranjith Kumar, Ramanathan [Department of Plant Biology and Plant Biotechnology, Shree Chandraprabhu Jain College, Chennai (India); Hanumantha Rao, Polur [Department of Microbiology, Madras Christian College, Chennai (India); Arumugam, Muthu, E-mail: arumugam@niist.res.in [Division of Biotechnology, CSIR – National Institute for Interdisciplinary Science and Technology (NIIST), Trivandrum (India)

    2015-01-08

    Energy security has become a serious global issue and a lot of research is being carried out to look for economically viable and environment-friendly alternatives. The only solution that appears to meet futuristic needs is the use of renewable energy. Although various forms of renewable energy are being currently used, the prospects of producing carbon-neutral biofuels from microalgae appear bright because of their unique features such as suitability of growing in open ponds required for production of a commodity product, high CO{sub 2}-sequestering capability, and ability to grow in wastewater/seawater/brackish water and high-lipid productivity. The major process constraint in microalgal biofuel technology is the cost-effective and efficient extraction of lipids. The objective of this article is to provide a comprehensive review on various methods of lipid extraction from microalgae available, to date, as well as to discuss their advantages and disadvantages. The article covers all areas of lipid extraction procedures including solvent extraction procedures, mechanical approaches, and solvent-free procedures apart from some of the latest extraction technologies. Further research is required in this area for successful implementation of this technology at the production scale.

  20. Phycoremediation of Tannery Wastewater Using Microalgae Scenedesmus Species.

    Science.gov (United States)

    Ajayan, Kayil Veedu; Selvaraju, Muthusamy; Unnikannan, Pachikaran; Sruthi, Palliyath

    2015-01-01

    A number of microalgae species are efficient in removing toxicants from wastewater. Many of these potential species are a promising, eco-friendly, and sustainable option for tertiary wastewater treatment with a possible advantage of improving the economics of microalgae cultivation for biofuel production. The present study deals with the phycoremediation of tannery wastewater (TWW) using Scenedesmus sp. isolated from a local habitat. The test species was grown in TWW under laboratory conditions and harvested on the 12th day. The results revealed that the algal biomass during the growth period not only reduced the pollution load of heavy metals (Cr-81.2-96%, Cu-73.2-98%, Pb-75-98% and Zn-65-98%) but also the nutrients (NO3 >44.3% and PO4 >95%). Fourier Transform Infrared (FTIR) spectrums of Scenedesmus sp. biomass revealed the involvement of hydroxyl amino, carboxylic and carbonyl groups. The scanning electron micrograph (SEM) and Energy Dispersive X-ray Spectroscopic analysis (EDS) revealed the surface texture, morphology and element distribution of the biosorbent. Furthermore, the wastewater generated during wet-blue tanning process can support dense population of Scenedesmus sp., making it a potential growth medium for biomass production of the test alga for phycoremediation of toxicants in tannery wastewaters.

  1. 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.

  2. Lipid Extraction Methods from Microalgae: A Comprehensive Review

    International Nuclear Information System (INIS)

    Ranjith Kumar, Ramanathan; Hanumantha Rao, Polur; Arumugam, Muthu

    2015-01-01

    Energy security has become a serious global issue and a lot of research is being carried out to look for economically viable and environment-friendly alternatives. The only solution that appears to meet futuristic needs is the use of renewable energy. Although various forms of renewable energy are being currently used, the prospects of producing carbon-neutral biofuels from microalgae appear bright because of their unique features such as suitability of growing in open ponds required for production of a commodity product, high CO 2 -sequestering capability, and ability to grow in wastewater/seawater/brackish water and high-lipid productivity. The major process constraint in microalgal biofuel technology is the cost-effective and efficient extraction of lipids. The objective of this article is to provide a comprehensive review on various methods of lipid extraction from microalgae available, to date, as well as to discuss their advantages and disadvantages. The article covers all areas of lipid extraction procedures including solvent extraction procedures, mechanical approaches, and solvent-free procedures apart from some of the latest extraction technologies. Further research is required in this area for successful implementation of this technology at the production scale.

  3. 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.

  4. 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.

  5. 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)

  6. 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)

  7. Biologia floral e sistema reprodutivo de duas espécies de marantaceae no Nordeste do Brasil : Ischnosiphon gracilis (Rudge) Köern. e Stromanthe porteana A. Gris

    OpenAIRE

    Virgínia de Lima Leite, Ana

    2002-01-01

    As espécies de Marantaceae apresentam um elaborado mecanismo de polinização caracterizado pela apresentação secundária de pólen associada a um mecanismo explosivo do estilete. Neste trabalho foram feitas análises da biologia floral e do sistema reprodutivo em populações naturais de Ischnosiphon gracilis (Rudge) Köern. e Stromanthe porteana A. Gris ocorrentes no Parque Estadual Dois Irmãos (8º7 30 S 34º52 30 W), estado de Pernambuco, Brasil. A inflorescência de I. gracil...

  8. 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.

  9. Modifications of the metabolic pathways of lipid and triacylglycerol production in microalgae

    Directory of Open Access Journals (Sweden)

    Yu Wei-Luen

    2011-11-01

    Full Text Available Abstract 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.

  10. Use of microalgae to recycle nutrients in aqueous phase derived from hydrothermal liquefaction process.

    Science.gov (United States)

    Leng, Lijian; Li, Jun; Wen, Zhiyou; Zhou, Wenguang

    2018-05-01

    Hydrothermal liquefaction (HTL) of microalgae biomass generates an aqueous phase (AP) byproduct with limited energy value. Recycling the AP solution as a source of nutrients for microalgae cultivation provides an opportunity for a cost-effective production of HTL based biofuel and algal biomass feedstock for HTL, allowing a closed-loop biofuel production in microalgae HTL biofuel system. This paper aims to provide a comprehensive overview of characteristics of AP and its nutrients recycling for algae production. Inhibitory effects resulted from the toxic compounds in AP and alleviation strategies are discussed. Copyright © 2018 Elsevier Ltd. All rights reserved.

  11. 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.

  12. Isolation and application of SOX and NOX resistant microalgae in biofixation of CO2 from thermoelectricity plants

    International Nuclear Information System (INIS)

    Radmann, Elisangela Martha; Vieira Camerini, Felipe; Duarte Santos, Thaisa; Vieira Costa, Jorge Alberto

    2011-01-01

    Highlights: → Microalgae can help reduce global warming. → Synechococcus nidulans and Chlorella vulgaris were isolated in a thermoelectric plant. → Microalgae were compared with Spirulina and Scenedesmus obliquus for CO 2 fixation. → Microalgae were exposed to CO 2 , SO 2 and NO, simulating a gas from coal combustion. → C. vulgaris and Spirulina sp. showed 13.43% of maximum daily fixation. - Abstract: Microalgae have been studied for their potential use in foodstuffs, agriculture, in the treatment of wastewater and, in particular, in the reduction of atmospheric carbon dioxide, the main cause of global warming. Thermoelectricity plants account for 22% of CO 2 emitted into the atmosphere and native microalgae may be more tolerant to the gases emitted from burning fossil fuels. In the study presented here, microalgae were isolated from ponds next to a Thermoelectricity Plant, located in southern Brazil, and identified as Synechococcus nidulans and Chlorella vulgaris. The isolated microalgae were grown and compared with two different strains of microalgae, Spirulina sp. and Scenedesmus obliquus, for CO 2 biofixation. The microalgae were exposed to 12% CO 2 , 60 ppm of SO 2 and 100 ppm of NO, simulating a gas from coal combustion. The C. vulgaris had similar behavior to Spirulina sp., with 13.43% of maximum daily fixation. The microalgae with the greater fixing capacity were C. vulgaris and Spirulina sp. and these can be grown in electric power plants for CO 2 biofixation of the coal combustion gas, which would help reduce global warming.

  13. Use of alternative media and different types of recipients in a laboratory culture of Ankistrodesmus gracilis (Reinsch Korshikov (Chlorophyceae = Utilização de meios alternativos e diferentes tipos de recipientes no cultivo de Ankistrodesmus gracilis (Reinsch Korshikov (Chlorophyceae em laboratório.

    Directory of Open Access Journals (Sweden)

    Lucia Helena Sipauba-Tavares

    2011-07-01

    Full Text Available A laboratory culture of Ankistrodesmus gracilis algae was evaluated by studying the biology of the species and its chemical composition in a traditional medium (CHU12 and in two alternative culture media, NPK (20-5-20 and macrophyte (Eichhornia crassipes + NPK, in three different types of recipients (fiberglass, carboy and plastic bag. First peak in the growth curve of Ankistrodesmus gracilis occurred on the ninth day in macrophyte + NPK medium (74.16 x 105 cells mL-1 in a fiberglass recipient. However, highest density (p 0.05 in culture media in the three recipients. Protein and fiber were similar (p > 0.05 in the treatments, but lipids were higher (p O objetivo do estudo foi avaliar os aspectos biológicos e a composição química da alga Ankistrodesmus gracilis em laboratório utilizando um meio tradicional (CHU12 e dois meios alternativos, NPK (20-5-20 e macrófita (Eichhornia crassipes + NPK em três diferentes tipos de recipientes (cuba de fibra de vidro translúcido, garrafões e saco plástico. O primeiro pico de densidade celular de Ankistrodesmus gracilis ocorreu no nono dia da curva de crescimento em meio macrófita+NPK (74,16 x 105 células mL-1 no recipiente de fibra de vidro, porém a maior densidade (p 0,05 nos três recipientes e meios de cultivo. Os teores de proteína e fibra foram similares (p > 0,05 nos tratamentos utilizados, já os de lipídios foram mais elevados (p < 0,05 no meio NPK. Os teores médios de nitrato, amônia, fósforo total e ortofosfato estiveram acima de 1 mg L-1 no meio NPK (p < 0,01. Os resultados obtidos neste estudo indicam a possibilidade do uso de meios alternativos como o NPK e macrophyte +NPK para o cultivo de A. gracilis em larga escala cultivados nos três tipos de recipientes, porém, em saco plástico o custo é baixo e ocupa menos espaço em cultivo de laboratório.

  14. Microencapsulation of single-cell protein from various microalgae species

    Directory of Open Access Journals (Sweden)

    Purnama Sukardi

    2015-10-01

    Full Text Available ABSTRACT The objective of the research was to evaluate nutritional values of microencapsulated diet made from single cell protein of microalgae. Complete randomized design was applied using three different types of microalgae for inclusion trials i.e. (A Nannochloropsis sp., (B Chlorella sp., and (C Spirulina sp. with five replications respectively. Microencapsulated diet was produced by a modification method based on thermal cross-linking with stable temperature. Phytoplankton was cultured in sea water for which fertilized by a modification of Walne and Guillard fertilizer. The results showed that the highest value of nutrition content was Spirulina sp. and the average composition of protein, crude lipid, carbohydrate, ash, nitrogen free extract, and water content was 34.80%, 0.30%, 18.53%, 20.09%, 26.29%, and 13.32%, respectively. Organoleptically, microcapsule showed that the color of capsule was dark green and smell fresh phytoplankton. Keywords: microcapsule, single-cell protein, thermal cross-linking, microalgae, phytoplankton  ABSTRAK Tujuan penelitian adalah mengevaluasi kandungan nutrisi pakan mikrokapsul protein sel tunggal (single cell protein yang berasal dari berbagai jenis mikroalga (fitoplankton. Rancangan percobaan yang digunakan adalah rancangan acak lengkap, dengan perlakuan inklusi mikrokapsul dari jenis fitoplankton (A Nannochloropsis sp., (B Chlorella sp., dan (C Spirulina sp., masing-masing diulang lima kali. Pembuatan mikrokapsul dilakukan dengan menggunakan modifikasi metode dasar thermal cross-linking, serta menerapkan teknik pengeringan suhu konstan. Proses pembuatan mikrokapsul protein diawali dengan kultur fitoplankton jenis Nannochloropsis sp., Chlorella sp., dan Spirulina sp. Kultur dilakukan di dalam laboratorium menggunakan media air laut dan modifikasi pupuk Walne dan Guillard. Hasil penelitian menunjukkan bahwa kandungan nutrisi tertinggi terdapat pada jenis mikrokapsul protein sel tunggal yang berasal dari

  15. Using Benthic microalgae to asses groundwater ecological status

    International Nuclear Information System (INIS)

    Tolivia, Analia A.; Kundt, Mirian S.; Iglicki, A.

    2009-01-01

    The water resources have been evaluated for a long time by physicochemical parameters. These provide timely results and do not reveal much about the evolution of a pollutant load and resilient and buffering capacity of aquatic ecosystems. Techniques based on the evaluation of sensitivity index of living organisms in the presence of different impacts have been developed as an alternative to these procedures. Biological indicator species are unique environmental indicators as they offer a signal of the biological condition in a watershed. The use of bio indicators as an early warning of pollution or degradation in an ecosystem can help sustain critical resources. While indicator species is a term that is often used, it is somewhat inaccurate. Indicators are actually groups or types of biological resources that can be used to assess environmental condition. Within each group, individual species can be used to calculate metrics in an effort to assess water quality conditions. Aquatic invertebrates and microalgae are the two groups recommended in evaluations of water quality, both are required by DMA 2000. The aim of this study was to evaluate two water bodies to choose the most appropriate group of microalgae to use as a biological indicator and establish the proposed rates that adjust better to describe the ecological quality of waters in the ecoregions where are the sites of CNEA. Surveys were carried out for this recognition of environments in the Ezeiza Atomic Center (CAE) and the industrial mining complex Los Gigantes, phytobenthos samples were taken in three sites in the Ezeiza Atomic Center (CAE) and the industrial mining complex Los Gigantes, Cordoba. Water samples were collected for later determination of chlorophyll content and biomass estimation. Determination of microalgal species were carried out and established those most representative groups. From that observation diatoms were selected as best represented in both sites. Some of the genera found in the

  16. Isolation, Characterization and Identification of Microalgae from the Red Sea

    KAUST Repository

    Luque Alanís, Patricio

    2013-05-01

    Eukaryotic microalgae from the Red Sea were isolated, characterized and identified with the purpose of building a culture collection that will serve future research activities in the area of industrial microbiology. Seven sampling locations were surveyed using an in-house designed isolation protocol. Microalgae enrichment was carried out in vitro using the streak plate method and fluorescence activated cell sorting approaches. Colonial and cellular microscopy, growth media preference assays, as well as temperature, pH and salinity tolerance tests were carried out to describe the isolates. DNA extraction, PCR amplification, template sequencing and in silico analyses were carried out to identify the isolates and arrange them in a proper phylogenetic description. In total, 129 isolates were obtained. From these, only 39 were selected for characterization given their increased ability of accumulating large amounts of biomass in solid and liquid media in relatively short periods of time. All of these have a green color, are unicellular, non-motile, photosynthetic organisms and have a cell size ranging from 5 to 8 µm. More than half of them showed growth preference in Walne media, followed by F/2, MN and BG-11 SW. Maximum temperature tolerance of all organisms was around 38 ºC, while optimum growth was observed close to 25 ºC. pH preference was diverse and three groups were identified: acidic (6), intermediate (8 - 9) and alkaline (> 10) growing isolates. Salinity tests showed an overall growth preference at 25 PSU, approximately 10 units lower than that found at the sampling stations. Most isolates showed diminished growth at high salinity and high pH, except for OS3S1b which grew well in both cases, and could be an interesting strain to study further. Twenty four isolates were related to Ulvophyceae sp. MBIC10591 by BLAST approaches with a maximum identity of 96 - 97%. A maximum likelihood phylogenetic tree was created for these isolates, relative to the BLAST hits

  17. 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.

  18. 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.

  19. 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.

  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....

  1. Analysis of microalgae pellets combustion in a circulating fluidized-bed

    Directory of Open Access Journals (Sweden)

    Kosowska-Golachowska Monika

    2017-01-01

    Full Text Available Microalgae are expected to become an important source of highvalue products with several applications in a large number of areas of biotechnology and, especially, in biofuels production. The increasing interest in microalgae as a source of biofuel (so-called third generation biofuel is due to the several advantages. The objective of this study was to investigate combustion characteristics of microalgae (Oscillatoria sp. pellets burnt in a circulating fluidized-bed (CFB in terms of sample temperature profiles, ignition time, ignition temperature, devolatilization time and the burnout time. Spherical 10-mm microalgae pellets were tested at temperature of 850°C in a 12-kW bench-scale CFB combustor.

  2. 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.

  3. 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.

  4. 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.

  5. Discrimination of Pigments of Microalgae, Bacteria and Yeasts Using Lightweight Handheld Raman Spectrometers: Prospects for Astrobiology

    Science.gov (United States)

    Jehlicka, J.; Osterrothova, K.; Nedbalova, L.; Gunde-Cimerman, N.; Oren, A.

    2014-06-01

    Handheld Raman instrumentation with 532 nm lasers can be used to distinguish carotenoids of autotrophic microalgae, purple sulfur bacteria, halophilic Archaea and pigmented yeasts. Pigments are proposed as biomarkers for astrobiology of Mars.

  6. 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.

  7. A Saponification Method for Chlorophyll Removal from Microalgae Biomass as Oil Feedstock

    Science.gov (United States)

    Li, Tao; Xu, Jin; Wu, Hualian; Wang, Guanghua; Dai, Shikun; Fan, Jiewei; He, Hui; Xiang, Wenzhou

    2016-01-01

    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. PMID:27618070

  8. 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.

  9. Isolation and Characterization of Native Microalgae from the Peruvian Amazon with Potential for Biodiesel Production

    Directory of Open Access Journals (Sweden)

    Marianela Cobos

    2017-02-01

    Full Text Available Biodiesel production from microalgae triacylglycerols is growing, because this feedstock is a more sustainable and advantageous alternative. In this study, we isolated and identified fourteen strains of native microalgae from the Peruvian Amazon. These strains showed great heterogeneity in biomass productivity, lipid productivity and lipid content, and thus, three of them (Acutodesmus obliquus, Ankistrodesmus sp. and Chlorella lewinii were selected for further evaluation under culture of nitrogen-sufficient (+N and nitrogen-deficient (−N Chu medium No. 10. These microalgae species showed modifications in biomolecule content (protein, lipid and carbohydrate with a pronounced increase of lipids and carbohydrate and a decrease of protein content under stress culture. Furthermore, the fatty acid profile was peculiar for each species, and these patterns showed evident changes, particularly in the proportion of saturated and monounsaturated fatty acids. The results of this research suggest that the isolated native microalgae, from the Peruvian Amazon, could be suitable candidates for biodiesel production

  10. A Saponification Method for Chlorophyll Removal from Microalgae Biomass as Oil Feedstock.

    Science.gov (United States)

    Li, Tao; Xu, Jin; Wu, Hualian; Wang, Guanghua; Dai, Shikun; Fan, Jiewei; He, Hui; Xiang, Wenzhou

    2016-09-07

    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.

  11. A review of the ecology, ecophysiology and biodiversity of microalgae in Arctic soil crusts

    Czech Academy of Sciences Publication Activity Database

    Pushkareva, E.; Johansen, J. R.; Elster, Josef

    2016-01-01

    Roč. 39, č. 12 (2016), s. 2227-2240 ISSN 0722-4060 Institutional support: RVO:67985939 Keywords : Soil crust * Arctic * Cyanobacteria and eukaryotic microalgae Subject RIV: EH - Ecology, Behaviour Impact factor: 1.949, year: 2016

  12. 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

  13. Involuntary movement during mastication in patients with long-term facial paralysis reanimated with a partial gracilis free neuromuscular flap innervated by the masseteric nerve.

    Science.gov (United States)

    Rozen, Shai; Harrison, Bridget

    2013-07-01

    Midface reanimation in patients with chronic facial paralysis is not always possible with an ipsilateral or contralateral facial nerve innervating a free neuromuscular tissue transfer. Alternate use of nonfacial nerves is occasionally indicated but may potentially result in inadvertent motions. The goal of this study was to objectively review videos of patients who underwent one-stage reanimation with a gracilis muscle transfer innervated by the masseteric nerve for (1) inadvertent motion during eating, (2) characterization of masticatory patterns, and (3) social hindrance perceived by the patients during meals. Between the years 2009 and 2012, 18 patients underwent midfacial reanimation with partial gracilis muscle transfer coapted to the masseter nerve for treatment of midfacial paralysis. Sixteen patients were videotaped in detail while eating. Involuntary midface movement on the reconstructed side and mastication patterns were assessed. In addition, 16 patients were surveyed as to whether involuntary motion constituted a problem in their daily lives. All 16 patients videotaped during mastication demonstrated involuntary motion on the reconstructed side while eating. Several unique masticatory patterns were noted as well. Only one of the 16 patients reported involuntary motion as a minor disturbance in daily life during meals. All patients with chronic facial paralysis who plan to undergo midface reanimation with a free tissue transfer innervated by the ipsilateral masseter nerve should be told that they would universally have involuntary animation during mastication. Most patients do not consider this a major drawback in their daily lives. Therapeutic, IV.

  14. Use of gastrointestinal anastomosis stapler for harvest of gracilis muscle and securing it in the face for facial reanimation: a novel technique.

    Science.gov (United States)

    Shridharani, Sachin M; Stapleton, Sahael M; Redett, Richard J; Magarakis, Michael; Rosson, Gedge D

    2010-04-08

    The primary objective of this study is to report a novel technique that uses the gastrointestinal anastomosis (GIA) stapler for harvesting and securing the gracilis muscle in facial reanimation surgery. We conducted a retrospective chart review with 18 consecutive patients who underwent gracilis muscle flap transfer with or without the use of a GIA stapler. Of 11 operations with the GIA stapler, one patient developed a hematoma (donor site) and another required drainage of an abscess (recipient site). Of 8 operations without the use of the stapler, one patient had total flap failure and three required drainage of an abscess (2 recipient sites and 1 donor site). These differences trended toward improvement but were not statistically different. The use of the GIA stapler is a fast, safe technique. Larger studies are, however, warranted to further examine this novel approach in order to test precisely what factors of increased efficiency occur, the amount of suture pull-through, and overall tension capable of being applied to the secured staple line.

  15. Pilot scale harvesting, separation and drying of microalgae biomass from compact photo-bioreactor

    Energy Technology Data Exchange (ETDEWEB)

    Cardoso, Alberto Tadeu Martins; Luz Junior, Luiz Fernando de Lima [Dept. de Engenharia Quimica. Universidade Federal do Parana, Curitiba, PR (Brazil)], e-mail: luzjr@ufpr.br; Mariano, Andre Bellin; Ghidini, Luiz Francisco Correa; Gnoatto, Victor Eduardo; Locatelli Junior, Vilson; Mello, Thiago Carvalho de; Vargas, Jose Viriato Coelho [Nucleo de Pesquisa e Desenvolvimento em Energia Autossustentavel (NPDEAS). Dept. de Engenharia Mecanica. Universidade Federal do Parana, Curitiba (Brazil)], E-mail: jvargas@demec.ufpr.br

    2010-07-01

    Bio diesel produced from microalgae lipids is gaining a substantial ground in the search for renewable energy sources. In order to optimize the operating conditions of a continuous process, several experiments were realized, both in laboratory and pilot scale. The microalgae cultivation can be conducted in a photo-bioreactor, a closed system which allows parameters control and necessarily involves the aquatic environment. Because of that, the use of separation unit operations is required. The process starts in a proposed compact photo-bioreactor, which consist of a chain of transparent tubes with 6 cm of diameter arranged in parallel where the cultivation media circulate with the help of a pump. This arrangement offers a closed culture with less risk of contamination and maintains a minimum contact with the environment. The microalgae grow inside the pipes under incidence of ambient light. In this paper, harvesting, separation and drying were studied, as part of the processes of a sustainable energy plant under construction at UFPR, as shown in Fig. 1. To control the production in a photo-bioreactor in continuous system, it is necessary to monitor the concentration of microalgae growth in suspension. To measure the cell concentration in this equipment, an optic sensor has been developed. The microalgae biomass separation from the culture media is achieved by microalgae flocculation. Several cultivation situations have been tested with different NaOH concentrations, increasing the pH to 10. The system was kept under agitation during the addition by an air pump into the tank. Thereafter the system was maintained static. After a short time, it was observed that the microalgae coagulated and settled. The clarified part water was removed, remaining a concentrated microalgae suspension. Our results suggest that pH increase is a suitable methodology for microalgae separation from the growth suspension. The microalgae sedimentation time was recorded, which allowed the

  16. Development of harvesting and up concentration technologies for microalgae as an ingredient in fish feed

    DEFF Research Database (Denmark)

    Safafar, Hamed; Jacobsen, Charlotte; Møller, Per

    2014-01-01

    andfish oil. In applications of algae in fish feed, it is essential to produce a product comparable to fish proteinand fish oil both in terms of quality and costs.Downstream processing of microalgae includes harvest, dewatering, cell rupture, fractionation and drying.The dewatering and drying which...... ingredients forfish feed. Further we evaluate the chemical composition of six different microalgae species including;Nanochloropsis limnethica, Chlorella sorokiniana, Phaeodactylum tinctorium, Dunaliella salina,Nannochloropsis salina and Nannochloropsis occulata ....

  17. Quantification of Heavy Metals and Other Inorganic Contaminants on the Productivity of Microalgae

    OpenAIRE

    Napan, Katerine; Hess, Derek; McNeil, Brian; Quinn, Jason C.

    2015-01-01

    Increasing demand for renewable fuels has researchers investigating the feasibility of alternative feedstocks, such as microalgae. Inherent advantages include high potential yield, use of non-arable land and integration with waste streams. The nutrient requirements of a large-scale microalgae production system will require the coupling of cultivation systems with industrial waste resources, such as carbon dioxide from flue gas and nutrients from wastewater. Inorganic contaminants present in t...

  18. Chemical composition of microalgae Heterochlorella luteoviridis and Dunaliella tertiolecta with emphasis on carotenoids.

    Science.gov (United States)

    Diprat, Andressa Bacalau; Menegol, Tania; Boelter, Juliana Ferreira; Zmozinski, Ariane; Rodrigues Vale, Maria Goreti; Rodrigues, Eliseu; Rech, Rosane

    2017-08-01

    Microalgae have been used as food supplements owing to their high protein, polyunsaturated fatty acid and carotenoid contents. As different carotenoids have distinct properties and the carotenoid composition of microalgae has been poorly explored in the literature, this study determined the complete carotenoid composition of two microalgae species, Heterochlorella luteoviridis and Dunaliella tertiolecta, using high-performance liquid chromatography coupled with diode array detection and tandem mass spectrometry (HPLC-DAD/MS 2 ). Additionally, the proximate composition and major minerals were evaluated. The carotenoid composition of the two microalgae was similar, with 13 carotenoids being found in H. luteoviridis and 12 in D. tertiolecta. The major carotenoids were all-trans-lutein (1.18 mg g -1 in H. luteoviridis and 1.59 mg g -1 in D. tertiolecta), all-trans-violaxanthin (0.52 mg g -1 in H. luteoviridis and 0.45 mg g -1 in D. tertiolecta) and all-trans-β-carotene (0.50 mg g -1 in H. luteoviridis and 0.62 mg g -1 in D. tertiolecta). All-trans-lutein was the predominant carotenoid in both microalgae, representing around 40% (mass fraction) of the total carotenoids. The lutein content found in these microalgae was significantly higher (2-40 times) than that in other important food sources of lutein (e.g. parsley, carrot, red pepper and broccoli). The microalgae H. luteoviridis and D. tertiolecta are excellent sources of lutein that could be commercially exploited by the food and pharmaceutical industries. Moreover, it was confirmed that both microalgae are good sources of protein, lipids and calcium. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  19. Applications of Diatoms as Potential Microalgae in Nanobiotechnology

    Directory of Open Access Journals (Sweden)

    Ahmad Yari Khosroushahi

    2012-05-01

    Full Text Available 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 recent progress in this century on the application of diatoms in waste degradation, synthesis of biomaterial, biomineraliza­tion, toxicity and toxic effects of mineral elements evaluations. Conclusion: Diatoms can be considered as metal toxicity bioindicators and they can be applied for biomineralization, synthesis of biomaterials, and degradation of wastes.

  20. Commercialization potential aspects of microalgae for biofuel production: An overview

    Directory of Open Access Journals (Sweden)

    Tahani S. Gendy

    2013-06-01

    This article discusses the importance of algae-based biofuels together with the different opinions regarding its future. Advantages and disadvantages of these types of biofuels are presented. Algal growth drives around the world with special emphasis to Egypt are outlined. The article includes a brief description of the concept of algal biorefineries. It also declares the five key strategies to help producers to reduce costs and accelerate the commercialization of algal biodiesel. The internal strengths and weaknesses, and external opportunities, and threats are manifested through the SWOT analysis for micro-algae. Strategies for enhancing algae based-fuels are outlined. New process innovations and the role of genetic engineering in meeting these strategies are briefly discussed. To improve the economics of algal biofuels the concept of employing algae for wastewater treatment is presented.

  1. Extraction of oil from microalgae for biodiesel production: A review.

    Science.gov (United States)

    Halim, Ronald; Danquah, Michael K; Webley, Paul A

    2012-01-01

    The rapid increase of CO(2) concentration in the atmosphere combined with depleted supplies of fossil fuels has led to an increased commercial interest in renewable fuels. Due to their high biomass productivity, rapid lipid accumulation, and ability to survive in saline water, microalgae have been identified as promising feedstocks for industrial-scale production of carbon-neutral biodiesel. This study examines the principles involved in lipid extraction from microalgal cells, a crucial downstream processing step in the production of microalgal biodiesel. We analyze the different technological options currently available for laboratory-scale microalgal lipid extraction, with a primary focus on the prospect of organic solvent and supercritical fluid extraction. The study also provides an assessment of recent breakthroughs in this rapidly developing field and reports on the suitability of microalgal lipid compositions for biodiesel conversion. Copyright © 2012 Elsevier Inc. All rights reserved.

  2. Antifouling potential of the marine microalga Dunaliella salina.

    Science.gov (United States)

    Gao, Min; Li, Fengchao; Su, Rongguo; Wang, Ke; Li, Xuzhao; Lu, Wei

    2014-11-01

    Marine organisms have usually been viewed as sources of environmentally friendly compounds with antifouling activity. We performed a series of operations to investigate the antifouling potential of the marine microalga Dunaliella salina. For the ethyl acetate crude extract, the antialgal activity was significant, and the EC50 value against Skeletonema costatum was 58.9 μg ml(-1). The isolated purified extract was tested for antifouling activity, the EC 50 value against S. costatum was 21.2 μg ml(-1), and the LC50 against Balanus amphitrite larvae was 18.8 μg ml(-1). Subsequently, both UHR-TOF-MS and GC-MS were used for the structural elucidation of the compounds, and a series of unsaturated and saturated 16- and 18-carbon fatty acids were detected. The data suggested that the fatty acid extracts from D. salina possess high antifouling activity, and could be used as substitutes for potent, toxic antifouling compounds.

  3. Aeration strategy for biofilm cultivation of the microalga Scenedesmus dimorphus.

    Science.gov (United States)

    Ji, Chunli; Wang, Junfeng; Liu, Tianzhong

    2015-10-01

    Biofilm cultivation of microalgae may be useful for biofuel production. However, many aspects for this cultivation method have not been well assessed. Accordingly, aeration strategy for biofilm cultivation of Scenedesmus dimorphus has been explored. Biomass, lipid and triacylglycerol (TAG) productivity in increased S. dimorphus as the CO2 concentration increased within 0.038-0.5% and kept constant with further increases. The biomass, lipid and TAG productivity increased with the speed increasing and an obvious threshold point was observed at 6.6 ml(-2) min(-1). The lipid and TAG content was unaffected by the aeration rate. Both the CO2 concentration as well as aeration speed affected the growth of S. dimorphus in biofilm cultivation. The optimized aeration strategy for biofilm cultivation was continuous air flow enriched with 1% CO2 (v/v) at 6.6 ml(-2) min(-1).

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

    DEFF Research Database (Denmark)

    Podevin, Michael Paul Ambrose

    sorokniana was grown on bioindustrial WW, inside a novel, solar tracking, 4000 L, airlift PBR. Despite cold temperatures and low irradiance, the microalgae reached a growth rate of 0.48 day-1 , in the four-day period immediately following inoculation of bioindustrial WW containing ammonium, as a primary...... to nitrate metabolism can severely stunt microalgal growth in the outdoor PBR under low temperature and irradiance. More importantly, the delay in growth did not appear to be due to deleterious effects of the contents of bioindustrial WW media, since rapid growth was observed early in the experiment...... vivo at large-scales. The complex and dynamic nature of large-scale outdoor microalgal reactions, when grown on dynamic WW media, encourages the need for on-line, real-time monitoring to improve automation models of PBRs. In outdoor conditions with fluctuating light and temperature, there are several...

  5. THIRD GENERATION BIODIESEL PRODUCTION FROM MICROALGAE Phormidium autumnale

    Directory of Open Access Journals (Sweden)

    S. F. Siqueira

    Full Text Available Abstract The aim of this work was to evaluate third generation biodiesel production by the microalgae Phormidium autumnale using sucrose as exogenous carbon source. The study focused on optimization of the different C/N ratios and on the analysis of biofuel quality. The results indicate that a C/N ratio of 40 improved the performance of the system, reaching single-cell oil productivities of 18.9 mg/L in steady-state conditions. This oil has a composition predominantly saturated (45.2% and monounsaturated (34.7% suitable for biodiesel synthesis (ester content of 99.8%, cetane number of 58.5%, iodine value of 67.2 gI2/100 g, unsaturation degree of 71.3% and a cold filter plugging point of 6.7 ºC.

  6. Carotenoids from microalgae: A review of recent developments.

    Science.gov (United States)

    Gong, Mengyue; Bassi, Amarjeet

    2016-12-01

    Carotenoids have been receiving increasing attention due to their potential health benefits. Microalgae are recognized as a natural source of carotenoids and other beneficial byproducts. However, the production of micro-algal carotenoids is not yet sufficiently cost-effective to compete with traditional chemical synthetic methods and other technologies such as extraction from plant based sources. This review presents the recent biotechnological developments in microalgal carotenoid production. The current technologies involved in their bioprocessing including cultivation, harvesting, extraction, and purification are discussed with a specific focus on downstream processing. The recent advances in chemical and biochemical synthesis of carotenoids are also reviewed for a better understanding of suitable and economically feasible biotechnological strategies. Some possible future directions are also proposed. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Growth of locally isolated microalga in POME to produce lipid as alternative energy sources

    Science.gov (United States)

    Elvitriana; Munir, E.; Delvian; Wahyuningsih, H.

    2018-04-01

    Purpose of this study was to find the best growth of locally isolated microalgae that produce lipids from Palm Oil Mill Effluent (POME) as an alternative energy source. Microalgae was cultivated in POME in glass vessel at room temperature using a lighting intensity of 13,000 lux and continuously aeration for 24 and 12 hours, respectively. Biomass of microalgae were analyzed daily to get their growth by spectrophotometry at 624 nm wavelength, whereas Modified Bligh and Dyer method determined lipid content. Results show that the best growth occurred at 10% inoculum with lighting cycle and aeration of 24 hours (on/off) and resulting highest biomass content of 0.99 g dry weight/L followed by the decrease of organic substances in POME. The percentage reduction of COD, BOD, TSS, and oil at POME reached above 92%, while phosphate concentration reached 89.2%. Cultivation of microalgae in POME for 12 days showed its ability to reduce organic substances and nutrients in POME and produced biomass with lipid content of 35%. These results reached to the conclusion that locally isolated microalgae has an ability to treat POME safely for environment and POME can be used as a growing medium of microalgae that produces lipids.

  8. Efficient harvesting of marine Chlorella vulgaris microalgae utilizing cationic starch nanoparticles by response surface methodology.

    Science.gov (United States)

    Bayat Tork, Mahya; Khalilzadeh, Rasoul; Kouchakzadeh, Hasan

    2017-11-01

    Harvesting involves nearly thirty percent of total production cost of microalgae that needs to be done efficiently. Utilizing inexpensive and highly available biopolymer-based flocculants can be a solution for reducing the harvest costs. Herein, flocculation process of Chlorella vulgaris microalgae using cationic starch nanoparticles (CSNPs) was evaluated and optimized through the response surface methodology (RSM). pH, microalgae and CSNPs concentrations were considered as the main independent variables. Under the optimum conditions of microalgae concentration 0.75gdry weight/L, CSNPs concentration 7.1mgdry weight/L and pH 11.8, the maximum flocculation efficiency (90%) achieved. Twenty percent increase in flocculation efficiency observed with the use of CSNPs instead of the non-particulate starch which can be due to the more electrostatic interactions between the cationic nanoparticles and the microalgae. Therefore, the synthesized CSNPs can be employed as a convenient and economical flocculants for efficient harvest of Chlorella vulgaris microalgae at large scale. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Potential of Microalgae Cultivation in Dairy Wastewater as a Step in Low-Cost Biofuel Production

    Directory of Open Access Journals (Sweden)

    Basma Abbas Abdulmajeed

    2018-04-01

    Full Text Available The present study addresses adopting the organic and nutritious materials in dairy wastewater as media for cultivation of microalgae, which represent an important source of renewable energy. This study was carried out through cultivation of three types of microalgae; Chlorella sp., Synechococcus, and Anabaena. The results shows the success the cultivation of the Synechococcus and Chlorella Sp, while the Anabaena microalgae were in low-growth level. The highest growth was in the Synechococcus farm, followed by Chlorella and Anabaena. However, the growth of Synechococcus required 10 days to achieve this increase that represents a negative indicator of the adoption of this type of microalgae in this media to meet the desired aims. While Chlorella needs less than two days to start growing. Moreover, the data obtained from the experiment show that removal of chemical oxygen demand in Chlorella cultures was (72% more than that obtained from cultivation of other microalgae. Thus this microalgae is more efficient in wastewater treatment than other types.

  10. Biodiesel from wet microalgae: extraction with hexane after the microwave-assisted transesterification of lipids.

    Science.gov (United States)

    Cheng, Jun; Huang, Rui; Li, Tao; Zhou, Junhu; Cen, Kefa

    2014-10-01

    A chloroform-free novel process for the efficient production of biodiesel from wet microalgae is proposed. Crude biodiesel is produced through extraction with hexane after microwave-assisted transesterification (EHMT) of lipids in wet microalgae. Effects of different parameters, including reaction temperature, reaction time, methanol dosage, and catalyst dosage, on fatty acids methyl esters (FAMEs) yield are investigated. The yield of FAME extracted into the hexane from the wet microalgae is increased 6-fold after the transesterification of lipids. The yield of FAME obtained through EHMT of lipids in wet microalgae is comparable to that obtained through direct transesterification of dried microalgae biomass with chloroform; however, FAME content in crude biodiesel obtained through EHMT is 86.74%, while that in crude biodiesel obtained through the chloroform-based process is 75.93%. EHMT ensures that polar pigments present in microalgae are not extracted into crude biodiesel, which leads to a 50% reduction in nitrogen content in crude biodiesel. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Pyrolysis mechanism of microalgae Nannochloropsis sp. based on model compounds and their interaction

    International Nuclear Information System (INIS)

    Wang, Xin; Tang, Xiaohan; Yang, Xiaoyi

    2017-01-01

    Highlights: • Pyrolysis experiments were conducted by model compounds of algal components. • Interaction affected little bio-crude yield of model compounds co-pyrolysis. • Some interaction pathways between microalgae components were recommended. • N-heterocyclic compounds were further pyrolysis products of Maillard reaction products. • Surfactant synthesis (lipid-amino acids and lipid-glucose) between algal components. - Abstract: Pyrolysis is one of important pathways to convert microalgae to liquid biofuels and key components of microalgae have different chemical composition and structure, which provides a barrier for large-scale microalgae-based liquid biofuel application. Microalgae component pyrolysis mechanism should be researched to optimal pyrolysis process parameters. In this study, single pyrolysis and co-pyrolysis of microalgal components (model compounds castor oil, soybean protein and glucose) were conducted to reveal interaction between them by thermogrametric analysis and bio-crude evaluation. Castor oil (model compound of lipid) has higher pyrolysis temperature than other model compounds and has the maximum contribution to bio-crude formation. Bio-crude from soybean protein has higher N-heterocyclic compounds as well as phenols, which could be important aromatic hydrocarbon source during biorefineries and alternative aviation biofuel production. Potential interaction pathways based on model compounds are recommended including further decomposition of Maillard reaction products (MRPs) and surfactant synthesis, which indicate that glucose played an important role on pyrolysis of microalgal protein and lipid components. The results should provide necessary information for microalgae pyrolysis process optimization and large-scale pyrolysis reactor design.

  12. Isolation and Characterisation of Some Microalgae Bioactive Molecules

    Directory of Open Access Journals (Sweden)

    Emeka Ugoala

    2016-12-01

    Full Text Available This study involved the isolation, structure elucidation, and biological screening of secondary metabolites in freshwater microalgae for bioactive and chemically novel compounds. Isolates were fractionated and purified from the methanol, ethyl acetate, dichloromethane, petroleum ether and aqueous extracts of microalgae via column chromatography technique over silica gel using a gradient mixture of solvents. The chemical structures of isolated compounds have been elucidated using Solid-state cross polarization (CP and magic angle spinning (MAS 13C-NMR spectroscopic technique at spectrometer frequency at a field strength corresponding to 91.3695 MHz for 13C and 363.331 MHz for 1H. Of the nine compounds isolated, eight have a glycan skeleton with attached amino acids units. Two of the eight contain beta amino acids units. These are not very common metabolites but hold promise as drug leads. The elements of diversity in the isolates were the gluco and manno configurations of the pyranose ring, the α-configurations at the anomeric centre, and the positions of the carbohydrate and amino acid sectors in the ring. These molecules are not easily available through gene technology since they are post translational products resulting from the activity of glycosyl hydrolases and transferases. The chemical shifts were rationalized in terms of the number of sugar residues, the sugar ring structures, the positions and anomeric configurations of the inter-sugar linkages. Considering all the NMR data, it was concluded that the compounds were glycylglycylglycylglycine, α-D-glucopyranosyl-2-amino-4-methylpentanoic acid, α-D-glucopyranosyl-2-methylamino-4-methylpentanoic acid, α-D-glucopyranosyl-2-amino-4-methylpentanoate, α-D-glucopyranosyl-glycylglycine, α-D-glucopyranosyl-3-aminobutanoic acid, α-D-glucopyranosyl-2,4,7-triaminooctantrioic acid, α-D-mannopyranosyl-2-amino-3-methylbutanoic acid and α-D-mannopyranosyl-3-aminobutanoic acid.

  13. Processing of Microalgae: Acoustic Cavitation and Hydrothermal Conversion

    Science.gov (United States)

    Greenly, Justin Michael

    The production of energy dense fuels from renewable algal biomass feedstocks -- if sustainably developed at a sufficiently large scale -- may reduce the consumption of petroleum from fossil fuels and provide many environmental benefits. Achieving economic feasibility has several technical engineering challenges that arise from dilute concentration of growing algae in aqueous media, small cell sizes, and durable cell walls. For microalgae to be a sustainable source of biofuels and co-products, efficient fractionation and conversion of the cellular contents is necessary. Research was carried out to address two processing options for efficient microalgae biofuel production: 1. Ultrasonic cavitation for cell disruption and 2. Hydrothermal conversion of a model algal triglyceride. 1. Ultrasonic cell disruption, which relies on cavitating bubbles in the suspension to produce damaging shock waves, was investigated experimentally over a range of concentrations and species types. A few seconds of high intensity sonication at fixed frequency yielded significant cell disruption, even for the more durable cells. At longer exposure times, effectiveness was seen to decline and was attributed, using acoustic measurements, to ultrasonic power attenuation in the ensuing cloud of cavitating bubbles. Processing at higher cell concentrations slowed cell disintegration marginally, but increased the effectiveness of dissipating ultrasonic energy. A theoretical study effectively predicted optimal conditions for a variety of parameters that were inaccessible in this experimental investigation. In that study, single bubble collapse was modeled to identify operating conditions that would increase cavitation, and thus cell disruption. Simulations were conducted by varying frequency and pressure amplitude of the ultrasound wave, and initial bubble size. The simulation results indicated that low frequency, high sound wave amplitudes, and small initial bubble size generate the highest shock

  14. Carotenoids of Microalgae Used in Food Industry and Medicine.

    Science.gov (United States)

    Gateau, Hélène; Solymosi, Katalin; Marchand, Justine; Schoefs, Benoît

    2017-01-01

    Since the industrial revolution, the consumption of processed food increased dramatically. During processing, food material loses many of its natural properties. The simple restoration of the original properties of the processed food as well as fortification require food supplementation with compounds prepared chemically or of natural origin. The observations that natural food additives are safer and better accepted by consumers than synthetic ones have strongly increased the demand for natural compounds. Because some of them have only a low abundance or are even rare, their market price can be very high. This is the case for most carotenoids of natural origin to which this review is dedicated. The increasing demand for food additives of natural origin contributes to an accelerated depletion of traditional natural resources already threatened by intensive agriculture and pollution. To overcome these difficulties and satisfy the demand, alternative sources for natural carotenoids have to be found. In this context, photosynthetic microalgae present a very high potential because they contain carotenoids and are able to produce particular carotenoids under stress. Their potential also resides in the fact that only ten thousands of microalgal strains have been described while hundred thousands of species are predicted to exist. Carotenoids have been known for ages for their antioxidant and coloring properties, and a large body of evidence has been accumulated about their health potential. This review summarizes both the medicinal and food industry applications of microalgae with emphasis on the former. In addition, traditional and alternative microalgal sources used for industrial carotenoid extraction, the chemical and physical properties, the biosynthesis and the localization of carotenoids in algae are also briefly discussed. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  15. Protein N-glycosylation in eukaryotic microalgae and its impact on the production of nuclear expressed biopharmaceuticals

    Directory of Open Access Journals (Sweden)

    Elodie eMathieu-Rivet

    2014-07-01

    Full Text Available Microalgae are currently used for the production of food compounds. Recently, few microalgae species have been investigated as potential biofactories for the production of biopharmaceuticals. Indeed in this context, microalgae are cheap, classified as Generally Recognized As Safe (GRAS organisms and can be grown easily. However, problems remain to be solved before any industrial production of microalgae-made biopharmaceuticals. Among them, post-translational modifications of the proteins need to be considered. Especially, N-glycosylation acquired by the secreted recombinant proteins is of major concern since most of the biopharmaceuticals are N-glycosylated and it is well recognized that glycosylation represent one of their critical quality attribute. Therefore, the evaluation of microalgae as alternative cell factory for biopharmaceutical productions thus requires to investigate their N-glycosylation capability in order to determine to what extend it differs from their human counterpart and to determine appropriate strategies for remodelling the microalgae glycosylation into human-compatible oligosaccharides. Here, we review the secreted recombinant proteins which have been successfully produced in microalgae. We also report on recent bioinformatics and biochemical data concerning the structure of glycans N-linked to proteins from various microalgae phyla and comment the consequences on the glycan engineering strategies that may be necessary to render those microalgae-made biopharmaceuticals compatible with human therapy.

  16. Mathematical modeling and experimental validation of Phaeodactylum tricornutum microalgae growth rate with glycerol addition

    Energy Technology Data Exchange (ETDEWEB)

    Morais, Keli Cristiane Correia; Ribeiro, Robert Luis Lara; Santos, Kassiana Ribeiro dos; Mariano, Andre Bellin [Mariano Center for Research and Development of Sustainable Energy (NPDEAS), Curitiba, PR (Brazil); Vargas, Jose Viriato Coelho [Departament of Mechanical Engineering, Federal University of Parana (UFPR) Curitiba, PR (Brazil)

    2010-07-01

    The Brazilian National Program for Bio fuel Production has been encouraging diversification of feedstock for biofuel production. One of the most promising alternatives is the use of microalgae biomass for biofuel production. The cultivation of microalgae is conducted in aquatic systems, therefore microalgae oil production does not compete with agricultural land. Microalgae have greater photosynthetic efficiency than higher plants and are efficient fixing CO{sub 2}. The challenge is to reduce production costs, which can be minimized by increasing productivity and oil biomass. Aiming to increase the production of microalgae biomass, mixotrophic cultivation, with the addition of glycerol has been shown to be very promising. During the production of biodiesel from microalgae there is availability of glycerol as a side product of the transesterification reaction, which could be used as organic carbon source for microalgae mixotrophic growth, resulting in increased biomass productivity. In this paper, to study the effect of glycerol in experimental conditions, the batch culture of the diatom Phaeodactylum tricornutum was performed in a 2-liter flask in a temperature and light intensity controlled room. During 16 days of cultivation, the number of cells per ml was counted periodically in a Neubauer chamber. The calculation of dry biomass in the control experiment (without glycerol) was performed every two days by vacuum filtration. In the dry biomass mixotrophic experiment with glycerol concentration of 1.5 M, the number of cells was assessed similarly in the 10{sup th} and 14{sup th} days of cultivation. Through a volume element methodology, a mathematical model was written to calculate the microalgae growth rate. It was used an equation that describes the influence of irradiation and concentration of nutrients in the growth of microalgae. A simulation time of 16 days was used in the computations, with initial concentration of 0.1 g l{sup -1}. In order to compare

  17. A geographical assessment of vegetation carbon stocks and greenhouse gas emissions on potential microalgae-based biofuel facilities in the United States.

    Science.gov (United States)

    Quiroz Arita, Carlos; Yilmaz, Özge; Barlak, Semin; Catton, Kimberly B; Quinn, Jason C; Bradley, Thomas H

    2016-12-01

    The microalgae biofuels life cycle assessments (LCA) present in the literature have excluded the effects of direct land use change (DLUC) from facility construction under the assumption that DLUC effects are negligible. This study seeks to model the greenhouse gas (GHG) emissions of microalgae biofuels including DLUC by quantifying the CO 2 equivalence of carbon released to the atmosphere through the construction of microalgae facilities. The locations and types of biomass and Soil Organic Carbon that are disturbed through microalgae cultivation facility construction are quantified using geographical models of microalgae productivity potential including consideration of land availability. The results of this study demonstrate that previous LCA of microalgae to biofuel processes have overestimated GHG benefits of microalgae-based biofuels production by failing to include the effect of DLUC. Previous estimations of microalgae biofuel production potential have correspondingly overestimated the volume of biofuels that can be produced in compliance with U.S. environmental goals. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Patrón reproductivo y talla media de madurez sexual de hembras de la langosta Panulirus gracilis (Decapoda: Palinuridae en Playa Lagarto, Guanacaste, Costa Rica

    Directory of Open Access Journals (Sweden)

    Helven Naranjo Madrigal

    2012-12-01

    Full Text Available La langosta Panulirus gracilis es importante como recurso pesquero de las comunidades costeras en el Pacífico Norte de Costa Rica. Debido a la importancia de actualizar el conocimiento relacionado con el patrón reproductivo de esta especie, se analizaron 357 especímenes de langostas P. gracilis hembras capturados mediante el buceo con compresor y el buceo a pulmón durante noviembre de 2007 a octubre del 2008 en Playa Lagarto. Se examinó la composición de las tallas por estrato de profundidad, el patrón mensual de la actividad reproductiva (IAR asociado al aumento relativo de la temperatura superficial del océano, y además se determinó la talla media de madurez sexual utilizando Modelos Lineales Generalizados. Los cuatro estados fisiológicos de madurez sexual mostraron que las hembras sin masa espermatófora y no ovígeras, presentaron las menores tallas con una media de 62.3mm de longitud cefalotoráxica (LC. Se observaron características de madurez sexual a partir de tallas muy bajas que van desde 30 a 50mm de LC, encontrándose la menor hembra ovígera reportada para esta especie de 35.8mm de LC y el mayor porcentaje de hembras maduras entre 70 y 80mm de LC. Los porcentajes del IAR se mantuvieron por encima del 50% durante el año, con excepción de los meses de octubre y enero. Además, se observó un aumento en el IAR que inició a partir de abril y continuó hasta agosto asociado a un relativo aumento en la temperatura a partir del mes de marzo, sin embargo esta relación no fue significativa (r²=0.49, p>0.05. No se descarta que la baja talla media de madurez sexual de 70.2mm de LC para P. gracilis en esta región sea causada por las prácticas de pesca. Se recomienda que se establezca una veda en la región de cinco meses (abril-agosto con el fin de proteger la estacionalidad reproductiva de la especie y promover un mayor reclutamiento a las áreas de pesca.

  19. Marine microalgae used as food supplements and their implication in preventing cardiovascular diseases

    Directory of Open Access Journals (Sweden)

    Mimouni Virginie

    2015-07-01

    Full Text Available Marine microalgae are photosynthetic microorganisms producing numerous bioactive molecules of interest for health and disease care such as lipids rich in omega-3 fatty acids -as eicosapentaenoic acid (EPA, 20:5 n-3 and docosahexaenoic acid (DHA, 22:6 n-3- and carotenoids (e.g., β-carotene, fucoxanthin, astaxanthin. It has already been shown that these molecules, individually used, are benefic in the prevention of diseases such as those associated with the cardiovascular risks, but also in some carcinomas. When these molecules are combined, synergistic effects may be observed. Microalgae, as a dietary supplement, can be used to study these synergistic effects in animal models in which dyslipidemia can be induced by a nutrition treatment. Different marine microalgae of interest are studied in this context to determine their potential effect as an alternative source to marine omega-3 rich fish oils, actually widely used for human health. Actually, the pharmaceutical and nutrition industries are developing health research programs involving microalgae, trying to limit the dramatic reduction of fish stocks and the associated pollution in the marine environment. The aim of this review is threefold: (1 to present research on lipids, particularly long chain polyunsaturated fatty acids, as components of marine microalgae used as food supplements; (2 to present the health benefits of some microalgae or their extracts, in particular in the prevention of cardiovascular diseases and (3 to highlight the role of Odontella aurita, a marine microalga rich in EPA used as food supplement with the aim of preventing cardiovascular diseases.

  20. Microalgae growth-promoting bacteria: A novel approach in wastewater treatment

    Directory of Open Access Journals (Sweden)

    Luz E. de-Bashan

    2003-07-01

    Full Text Available Plant growth-promoting bacteria (PGPB from the genus Azospirillum are known to enhance the growth of numerous agricultural crops. The use of these bacteria is proposed as "micro-algae-growth promoting bacteria" (MGPB for enhancing freshwater micro-algae Chlorella vulgaris and C. sorokiniana capadty to clean polluted water. The deliberate inoculation of Chlorella sp. with a terrestrial PGPB has not been reported prior to these studies, perhaps because of the different origin of the two micro-organisms. Chlorella spp. is not known to harbour any plant growth-promoting bacteria and Azospirillum sp. is rarely used for inoculation in aquatic environments. Co-immobilisation of C. vulgaris and A. brasilense Cd in small alginate beads resulted in significant increases in numerous micro-algae growth parameters. Dry and fresh weight, total number of cells, micro-algal cluster (colonies size within the bead, number of micro-algal cells per cluster and micro-algal pigments levels significantly increased. Lipids and the variety of fatty adds also significantly increased, as did the combination of micro-algae. MGPB had superior capacity for removing ammonium and phosphorus from polluted synthetic and municipal wastewaters than the micro-algae by itself. Other PGPB (i.e. Flavobacterium sp. Azospirillum sp. and Azotobacter sp. are currently being tested in aquaculture; carp farming using enhanced phytoplankton growth and stabilising mass marine micro-algae culture for use as feed for marine organisms are both retuming promising results. This aspect of PGPB effect on water micro-organisms is currently in its infancy. We pro pose that co-immobilising micro-algae and plant growth-promoting bacteria represent an effective means of increasing micro-algal populations and also their capacity for cleaning polluted water. Key words: PGPB; micro-algae; wastewater treatment; co-immobilised

  1. Setting the conditions for phycoremediation of radionuclide microalgae Dunaliella salina and Chlorella vulgaris

    International Nuclear Information System (INIS)

    Tatarova, D.; Galanda, D.; Kuruc, J.

    2016-01-01

    This presentation deals with bioremediation using microalgae - by phycoremediation. Microalgae are economically low profile compared to the plants, their cultivation can be carried out in laboratory conditions. They can survive in extreme conditions, they occur in all habitats and have faster growth. Halophilous green D. salina can accumulate heavy metals such as Zn, Cu and Cd. It occurs in hypersaline environment with tolerance (0.2 to 35) % NaCl. It contains high amounts of carotenoids, which protect it against formation of free radicals from UV radiation. Chlorella vulgaris is a representative of eukaryotic green microalgae with the highest chlorophyll content with the appearance in fresh water. Its phycoremediant ability are found in N and P elements, which are used as its nutritional components as well as for Cu, Cr, Cd, Pb, Au. The experiments were carried out using a peristaltic pump ISMATEC Model: ISM851 (flow rate 2 cm"3 min"-"1) followed by monitoring of time dependence of decrease of activity of the microalgae solutions. For evaluation of the samples was used HPGe gamma spectrometer (measurement time of the samples: 600 sec) from ORTEC Company and measured spectra were evaluated with software GammaVision from ORTEC. The measured results showed that the most effective phycoremediation of microalgae Dunaliella salina toke place in an environment of pH 3, and even more at pH 8. The fact that the D. salina is able of phycoremediation at so acidic pH can contribute to its applications in extreme conditions or in the coastal areas in view of that it is halophilic. At freshwater microalgae Chlorella vulgaris was found the best phytoremediation potential in its natural environment at pH of 6. Because this microalgae is freshwater, it may find application in inland or in liquid radioactive waste from nuclear facilities.(authors)

  2. Characterization of the flocculating agent from the spontaneously flocculating microalga Chlorella vulgaris JSC-7.

    Science.gov (United States)

    Alam, Md Asraful; Wan, Chun; Guo, Suo-Lian; Zhao, Xin-Qing; Huang, Zih-You; Yang, Yu-Liang; Chang, Jo-Shu; Bai, Feng-Wu

    2014-07-01

    High cost of biomass recovery is one of the bottlenecks for developing cost-effective processes with microalgae, particularly for the production of biofuels and bio-based chemicals through biorefinery, and microalgal biomass recovery through cell flocculation is a promising strategy. Some microalgae are naturally flocculated whose cells can be harvested by simple sedimentation. However, studies on the flocculating agents synthesized by microalgae cells are still very limited. In this work, the cell flocculation of a spontaneously flocculating microalga Chlorella vulgaris JSC-7 was studied, and the flocculating agent was identified to be cell wall polysaccharides whose crude extract supplemented at low dosage of 0.5 mg/L initiated the more than 80% flocculating rate of freely suspended microalgae C. vulgaris CNW11 and Scenedesmus obliquus FSP. Fourier transform infrared (FTIR) analysis revealed a characteristic absorption band at 1238 cm(-1), which might arise from PO asymmetric stretching vibration of [Formula: see text] phosphodiester. The unique cell wall-associated polysaccharide with molecular weight of 9.86×10(3) g/mol, and the monomers consist of glucose, mannose and galactose with a molecular ratio of 5:5:2. This is the first time to our knowledge that the flocculating agent from C. vulgaris has been characterized, which could provide basis for understanding the cell flocculation of microalgae and breeding of novel flocculating microalgae for cost-effective biomass harvest. Copyright © 2013 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  3. Enhanced Productivity of a Lutein-Enriched Novel Acidophile Microalga Grown on Urea

    Directory of Open Access Journals (Sweden)

    Carlos Vilchez

    2010-12-01

    Full Text Available Coccomyxa acidophila is an extremophile eukaryotic microalga isolated from the Tinto River mining area in Huelva, Spain. Coccomyxa acidophila accumulates relevant amounts of b-carotene and lutein, well-known carotenoids with many biotechnological applications, especially in food and health-related industries. The acidic culture medium (pH < 2.5 that prevents outdoor cultivation from non-desired microorganism growth is one of the main advantages of acidophile microalgae production. Conversely, acidophile microalgae growth rates are usually very low compared to common microalgae growth rates. In this work, we show that mixotrophic cultivation on urea efficiently enhances growth and productivity of an acidophile microalga up to typical values for common microalgae, therefore approaching acidophile algal production towards suitable conditions for feasible outdoor production. Algal productivity and potential for carotenoid accumulation were analyzed as a function of the nitrogen source supplied. Several nitrogen conditions were assayed: nitrogen starvation, nitrate and/or nitrite, ammonia and urea. Among them, urea clearly led to the best cell growth (~4 ´ 108 cells/mL at the end of log phase. Ammonium led to the maximum chlorophyll and carotenoid content per volume unit (220 mg·mL-1 and 35 mg·mL-1, respectively. Interestingly, no significant differences in growth rates were found in cultures grown on urea as C and N source, with respect to those cultures grown on nitrate and CO2 as nitrogen and carbon sources (control cultures. Lutein accumulated up to 3.55 mg·g-1 in the mixotrophic cultures grown on urea. In addition, algal growth in a shaded culture revealed the first evidence for an active xanthophylls cycle operative in acidophile microalgae.

  4. Effective cultivation of microalgae for biofuel production: a pilot-scale evaluation of a novel oleaginous microalga Graesiella sp. WBG-1.

    Science.gov (United States)

    Wen, Xiaobin; Du, Kui; Wang, Zhongjie; Peng, Xinan; Luo, Liming; Tao, Huanping; Xu, Yan; Zhang, Dan; Geng, Yahong; Li, Yeguang

    2016-01-01

    Commercial production of microalgal biodiesel is not yet economically viable, largely because of low storage lipid yield in microalgae mass cultivation. Selection of lipid-rich microalgae, thus, becomes one of the key research topics for microalgal biodiesel production. However, the laboratory screening protocols alone cannot predict the ability of the strains to dominate and perform in outdoor ponds. Comprehensive assessment of microalgae species should be performed not only under the laboratory conditions, but also in the fields. Laboratory investigations using a bubbled column photobioreactor indicated the microalga Graesiella sp. WBG-1 to be the most productive species among the 63 Chlorophyta strains. In a 10 L reactor, mimicking the industrial circular pond, Graesiella sp. WBG-1 produced 12.03 g biomass m(-2) day(-1) and 5.44 g lipids (45.23 % DW) m(-2) day(-1) under 15 mol m(-2) day(-1) artificial light irradiations. The lipid content decreased to ~34 % DW when the microalga was cultured in 30 L tank PBR under natural solar irradiations, but the decline of lipid content with scaling up was the minimum among the tested strains. Based on these results, the microalga was further tested for its lipid production and culture competitiveness using a pilot-scale raceway pond (200 m(2) illuminated area, culture volume 40,000 L). Consequently, Graesiella sp. WBG-1 maintained a high lipid content (33.4 % DW), of which ~90 % was storage TAGs. Results from the outdoor experiments indicated the nice adaptability of the Graesiella sp. WBG-1 to strong and fluctuating natural solar irradiance and temperature, and also demonstrated several other features, such as large cell size (easy for harvest and resistant to swallow by protozoa) and tolerance to high culture pH (helpful to CO2 fixation). Graesiella sp. WBG-1 was a promising strain capable of accumulating large amount of storage lipid under nature solar irradiance and temperature. The high lipid content

  5. Adaptation of microalgae to lindane: a new approach for bioremediation.

    Science.gov (United States)

    González, Raquel; García-Balboa, Camino; Rouco, Mónica; Lopez-Rodas, Victoria; Costas, Eduardo

    2012-03-01

    Lindane is especially worrisome because its persistence in aquatic ecosystems, tendency to bioaccumulation and toxicity. We studied the adaptation of freshwater cyanobacteria and microalgae to resist lindane using an experimental model to distinguish if lindane-resistant cells had their origin in random spontaneous pre-selective mutations (which occur prior to the lindane exposure), or if lindane-resistant cells arose by a mechanism of physiological acclimation during the exposure to the selective agent. Although further research is needed to determine the different mechanisms contributing to the bio-elimination of lindane, this study, however, provides an approach to the bioremediation abilities of the lindane-resistant cells. Wild type strains of the experimental organisms were exposed to increasing lindane levels to estimate lethal concentrations. Growth of wild-type cells was completely inhibited at 5mg/L concentration of lindane. However, after further incubation in lindane for several weeks, occasionally the growth of rare lindane-resistant cells was found. A fluctuation analysis demonstrated that lindane-resistant cells arise only by rare spontaneous mutations that occur randomly prior to exposure to lindane (lindane-resistance did not occur as a result of physiological mechanisms). The rate of mutation from lindane sensitivity to resistance was between 1.48 × 10(-5) and 2.35 × 10(-7) mutations per cell per generation. Lindane-resistant mutants exhibited a diminished fitness in the absence of lindane, but only these variants were able to grow at lindane concentrations higher than 5mg/L (until concentrations as high as 40 mg/L). Lindane-resistant mutants may be maintained in uncontaminated waters as the result of a balance between new resistant mutants arising from spontaneous mutation and resistant cells eliminated by natural selection waters via clone selection. The lindane-resistant cells were also used to test the potential of microalgae to remove

  6. Influence of thiamine on the post-irradiation effect caused by fast neutrons or gamma radiation in callus cultures of Haplopappus gracilis (Nutt) A. Gray

    International Nuclear Information System (INIS)

    Wajda, L.; Korzonek, M.

    1979-01-01

    Influence of thiamine within the investigated range of concentrations 1.5 to 12.0 mg/l on the postirradiation effect caused by fast neutrons or gamma irradiation was found in cultures of Haplopappus gracilis callus. The lowest sensitivity to fast neutrons was noticed in callus grown on nutrient combination 1.5 to 3.0 and 12.0 to 3.0 mg/l of thiamine. On the contrary the highest sensitivity to gamma radiation was shown by cultures grown on nutrient media: 1.5 to 3.0 mg/l; all the other investigated thiamine concentrations caused a marked decrease in the sensitivity of the callus. (author)

  7. Wastewater nutrient removal in a mixed microalgae-bacteria culture: effect of light and temperature on the microalgae-bacteria competition.

    Science.gov (United States)

    González-Camejo, J; Barat, R; Pachés, M; Murgui, M; Seco, A; Ferrer, J

    2018-02-01

    The aim of this study was to evaluate the effect of light intensity and temperature on nutrient removal and biomass productivity in a microalgae-bacteria culture and their effects on the microalgae-bacteria competition. Three experiments were carried out at constant temperature and various light intensities: 40, 85 and 125 µE m -2  s -1 . Other two experiments were carried out at variable temperatures: 23 ± 2°C and 28 ± 2°C at light intensity of 85 and 125 µE m -2  s -1 , respectively. The photobioreactor was fed by the effluent from an anaerobic membrane bioreactor. High nitrogen and phosphorus removal efficiencies (about 99%) were achieved under the following operating conditions: 85-125 µE m -2  s -1 and 22 ± 1°C. In the microalgae-bacteria culture studied, increasing light intensity favoured microalgae growth and limited the nitrification process. However, a non-graduated temperature increase (up to 32°C) under the light intensities studied caused the proliferation of nitrifying bacteria and the nitrite and nitrate accumulation. Hence, light intensity and temperature are key parameters in the control of the microalgae-bacteria competition. Biomass productivity significantly increased with light intensity, reaching 50.5 ± 9.6, 80.3 ± 6.5 and 94.3 ± 7.9 mgVSS L -1  d -1 for a light intensity of 40, 85 and 125 µE m -2  s -1 , respectively.

  8. Facial reanimation with gracilis muscle transfer neurotized to cross-facial nerve graft versus masseteric nerve: a comparative study using the FACIAL CLIMA evaluating system.

    Science.gov (United States)

    Hontanilla, Bernardo; Marre, Diego; Cabello, Alvaro

    2013-06-01

    Longstanding unilateral facial paralysis is best addressed with microneurovascular muscle transplantation. Neurotization can be obtained from the cross-facial or the masseter nerve. The authors present a quantitative comparison of both procedures using the FACIAL CLIMA system. Forty-seven patients with complete unilateral facial paralysis underwent reanimation with a free gracilis transplant neurotized to either a cross-facial nerve graft (group I, n=20) or to the ipsilateral masseteric nerve (group II, n=27). Commissural displacement and commissural contraction velocity were measured using the FACIAL CLIMA system. Postoperative intragroup commissural displacement and commissural contraction velocity means of the reanimated versus the normal side were first compared using the independent samples t test. Mean percentage of recovery of both parameters were compared between the groups using the independent samples t test. Significant differences of mean commissural displacement and commissural contraction velocity between the reanimated side and the normal side were observed in group I (p=0.001 and p=0.014, respectively) but not in group II. Intergroup comparisons showed that both commissural displacement and commissural contraction velocity were higher in group II, with significant differences for commissural displacement (p=0.048). Mean percentage of recovery of both parameters was higher in group II, with significant differences for commissural displacement (p=0.042). Free gracilis muscle transfer neurotized by the masseteric nerve is a reliable technique for reanimation of longstanding facial paralysis. Compared with cross-facial nerve graft neurotization, this technique provides better symmetry and a higher degree of recovery. Therapeutic, III.

  9. [Reproductive pattern and mean size of sexual maturity of female lobsters Panulirus gracilis (Decapoda: Palinuridae) in Playa Lagarto, Guanacaste, Costa Rica].

    Science.gov (United States)

    Naranjo Madrigal, Helven

    2012-12-01

    The lobster P. gracilis is important as a fishery resource and also contributes to food security of fishers in coastal communities in the North Pacific of Costa Rica. Due to the importance of updating knowledge related to the reproductive pattern of this species, we analyzed 357 specimens of female lobsters caught by the fishing methods of "hookah" and lung diving, from November 2007 to October 2008 in Playa Lagarto. Furthermore, we examined the size composition by depth; monthly pattern of reproductive activity (RAI) associated with the relative increase in sea surface temperature, and also the mean size at maturity using Generalized Linear Models. Four physiological states of sexual maturity showed that females with no signs of mating or sexual maturity have a minimum mean size of 62.3mm of cephalothorax length (CL). There are characteristics of functional maturity from very small sizes ranging from 30 to 50mm CL, being the smallest berried female reported for this specie of 35.8mm CL and the highest percentage of mature females between 70 and 80mm CL. Percentages of RAI remained above 50% during the year except October and January. In addition, it observed an increase in the RAI that started from April and continued until August associated with a relative increase in temperature on March, although the correlation was not significant (r2=0.49, p>0.05). It is possible that the low mean size at maturity (70.2mm LC) for P. gracilis in this region is related to the fishing activity. It recommends the establishment of a ban in the region of at least five months (April-August) in order to protect the reproductive seasonality of the species and to promote a recruitment increase in the fishing areas.

  10. Moringa oleifera Seed Derivatives as Potential Bio-Coagulant for Microalgae Chlorella sp. Harvesting

    International Nuclear Information System (INIS)

    Azizah Endut; Azizah Endut; Siti Hajar Abdul Hamid; Fathurrahman Lananan; Helena Khatoon

    2016-01-01

    Microalgae is an economical and potential raw material of biomass energy, which offer a wide range of commercial potential to produce valuable substances for applications in aquaculture feed, pharmaceutical purposes and bio fuels production. However, lack of an economical, efficient and convenient method to harvest microalgae is a bottleneck to boost their full-scale application. Hence, this study was performed to investigate the potentialities of Moringa oleifera seed derivatives as an environmentally bio-coagulant to harvest microalgae Chlorella sp. biomass from the water column, which acts as a binder to coagulate particulate impurities to form larger aggregates. Results shown M. oleifera to have better biomass recovery of 122.51 % as compared to 37.08 % of alum at similar dosages of 10 mgL"-"1. In addition, it was found that the zeta potential values of mixed microalgae-coagulant suspension shows positive correlation on the flocculation parameters. For biomass recovery, the correlation for M. oleifera protein powder showed the R"2-value of 0.9565 whereas the control chemical flocculant, alum with the R"2-value of 0.7920. It was evidence that M. oleifera has a great potential in efficient and economical for environmentally microalgae harvesting and the adaptation of biological harvesting technology especially for the purpose of aquaculture feed in Malaysia. (author)

  11. Recent Developments on Genetic Engineering of Microalgae for Biofuels and Bio-Based Chemicals.

    Science.gov (United States)

    Ng, I-Son; Tan, Shih-I; Kao, Pei-Hsun; Chang, Yu-Kaung; Chang, Jo-Shu

    2017-10-01

    Microalgae serve as a promising source for the production of biofuels and bio-based chemicals. They are superior to terrestrial plants as feedstock in many aspects and their biomass is naturally rich in lipids, carbohydrates, proteins, pigments, and other valuable compounds. Due to the relatively slow growth rate and high cultivation cost of microalgae, to screen efficient and robust microalgal strains as well as genetic modifications of the available strains for further improvement are of urgent demand in the development of microalgae-based biorefinery. In genetic engineering of microalgae, transformation and selection methods are the key steps to accomplish the target gene modification. However, determination of the preferable type and dosage of antibiotics used for transformant selection is usually time-consuming and microalgal-strain-dependent. Therefore, more powerful and efficient techniques should be developed to meet this need. In this review, the conventional and emerging genome-editing tools (e.g., CRISPR-Cas9, TALEN, and ZFN) used in editing the genomes of nuclear, mitochondria, and chloroplast of microalgae are thoroughly surveyed. Although all the techniques mentioned above demonstrate their abilities to perform gene editing and desired phenotype screening, there still need to overcome higher production cost and lower biomass productivity, to achieve efficient production of the desired products in microalgal biorefineries. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Efficient Anaerobic Digestion of Microalgae Biomass: Proteins as a Key Macromolecule.

    Science.gov (United States)

    Magdalena, Jose Antonio; Ballesteros, Mercedes; González-Fernandez, Cristina

    2018-05-06

    Biogas generation is the least complex technology to transform microalgae biomass into bioenergy. Since hydrolysis has been pointed out as the rate limiting stage of anaerobic digestion, the main challenge for an efficient biogas production is the optimization of cell wall disruption/hydrolysis. Among all tested pretreatments, enzymatic treatments were demonstrated not only very effective in disruption/hydrolysis but they also revealed the impact of microalgae macromolecular composition in the anaerobic process. Although carbohydrates have been traditionally recognized as the polymers responsible for the low microalgae digestibility, protease addition resulted in the highest organic matter solubilization and the highest methane production. However, protein solubilization during the pretreatment can result in anaerobic digestion inhibition due to the release of large amounts of ammonium nitrogen. The possible solutions to overcome these negative effects include the reduction of protein biomass levels by culturing the microalgae in low nitrogen media and the use of ammonia tolerant anaerobic inocula. Overall, this review is intended to evidence the relevance of microalgae proteins in different stages of anaerobic digestion, namely hydrolysis and methanogenesis.

  13. Microalgae Oil Production: A Downstream Approach to Energy Requirements for the Minamisoma Pilot Plant

    Directory of Open Access Journals (Sweden)

    Dhani S. Wibawa

    2018-02-01

    Full Text Available This study investigates the potential of microalgae oil production as an alternative renewable energy source, in a pilot project located at Minamisoma City in the Fukushima Prefecture of Japan. The algal communities used in this research were the locally mixed species, which were mainly composed of Desmodesmus collected from the Minamisoma pilot project. The microalgae oil-production processes in Minamisoma consisted of three stages: cultivation, dewatering, and extraction. The estimated theoretical input-energy requirement for extracting oil was 137.25 MJ to process 50 m3 of microalgae, which was divided into cultivation 15.40 MJ, centrifuge 13.39 MJ, drum filter 14.17 MJ, and hydrothermal liquefaction (HTL 94.29 MJ. The energy profit ratio (EPR was 1.41. The total energy requirement was highest in the HTL process (68% followed by cultivation (11% and the drum filter (10%. The EPR value increased along with the yield in the cultivation process. Using HTL, the microalgae biomass could be converted to bio-crude oil to increase the oil yield in the extraction process. Therefore, in the long run, the HTL process could help lower production costs, due to the lack of chemical additions, for extracting oil in the downstream estimation of the energy requirements for microalgae oil production.

  14. Study of Selecting on Light Source Used for Micro-algae Cultivation in Space

    Science.gov (United States)

    Ai, Weidang; Ai, Weidang; Guo, Shuang-Sheng; Gao, Feng; Tang, Yong-Kang; Qin, Li-Feng

    To select suitable light source for micro-algae cultivation in future space station, the selected Spirulina plastensis(No.7) were cultured under different lightening qualities, including six light sources that were made up of different combinations of red and blue light-emitting diode(LED). The growth, photosynthetic efficiency and nutrition quality of the Spirulina, were analyzed. From the experiments, the red light may promote the cumulation of biomass of the Spirulina, and the cumulating rate was the highest under all red light source, but the syntheses of protein, phycobiliprotein, β-carotene, VE and other nutrients needs a certain portion of blue light; yet, the complete blue light condition is not favorable to the growth of Spirulina, and may bring pollution by chlorella and other kinds of micro-algae. It is concluded that the LEDs can be used as the light resource of micro-algae cultivation. The normal growth and development of microalgae need two light sources of both red and blue LEDs. The comprehensive analyses of the various factors that affect the growth of Spirulina, such as nutrition quality and photosynthetic activities, etc., showed that the combination of 80% red and 20% blue LED is the optimum one among those tested combinations. Key word: light-emitting diode; micro-algae; controlled ecological life support system (CELSS); space cultivation

  15. Isolation and evaluation of oil-producing microalgae from subtropical coastal and brackish waters.

    Directory of Open Access Journals (Sweden)

    David K Y Lim

    Full Text Available Microalgae have been widely reported as a promising source of biofuels, mainly based on their high areal productivity of biomass and lipids as triacylglycerides and the possibility for cultivation on non-arable land. The isolation and selection of suitable strains that are robust and display high growth and lipid accumulation rates is an important prerequisite for their successful cultivation as a bioenergy source, a process that can be compared to the initial selection and domestication of agricultural crops. We developed standard protocols for the isolation and cultivation for a range of marine and brackish microalgae. By comparing growth rates and lipid productivity, we assessed the potential of subtropical coastal and brackish microalgae for the production of biodiesel and other oil-based bioproducts. This study identified Nannochloropsis sp., Dunaniella salina and new isolates of Chlorella sp. and Tetraselmis sp. as suitable candidates for a multiple-product algae crop. We conclude that subtropical coastal microalgae display a variety of fatty acid profiles that offer a wide scope for several oil-based bioproducts, including biodiesel and omega-3 fatty acids. A biorefinery approach for microalgae would make economical production more feasible but challenges remain for efficient harvesting and extraction processes for some species.

  16. RECOVERY AND SEQUESTRATION OF CO2 FROM STATIONARY COMBUSTION SYSTEMS BY PHOTOSYNTHESIS OF MICROALGAE

    Energy Technology Data Exchange (ETDEWEB)

    Dr. T. Nakamura; Dr. Miguel Olaizola; Dr. Stephen M. Masutani

    2002-12-01

    Most of the anthropogenic emissions of carbon dioxide result from the combustion of fossil fuels for energy production. Photosynthesis has long been recognized as a means, at least in theory, to sequester anthropogenic carbon dioxide. Aquatic microalgae have been identified as fast growing species whose carbon fixing rates are higher than those of land-based plants by one order of magnitude. Physical Sciences Inc. (PSI), Aquasearch, and the Hawaii Natural Energy Institute at the University of Hawaii are jointly developing technologies for recovery and sequestration of CO{sub 2} from stationary combustion systems by photosynthesis of microalgae. The research is aimed primarily at demonstrating the ability of selected species of microalgae to effectively fix carbon from typical power plant exhaust gases. This report covers the reporting period 1 July to 30 September 2002 in which PSI, Aquasearch and University of Hawaii conducted their tasks. Based on the work conducted during the previous reporting period, PSI initiated work on feasibility demonstration of direct feeding of coal combustion gas to microalgae. Aquasearch continued their effort on selection and characterization of microalgae suitable for CO{sub 2} sequestration. University of Hawaii continued effort on system optimization of the CO{sub 2} sequestration system.

  17. Microalgae Harvest through Fungal Pelletization—Co-Culture of Chlorella vulgaris and Aspergillus niger

    Directory of Open Access Journals (Sweden)

    Sarman Oktovianus Gultom

    2014-07-01

    Full Text Available Microalgae harvesting is a labor- and energy-intensive process and new approaches to harvesting microalgae need to be developed in order to decrease the costs. In this study; co-cultivatation of filamentous fungus (Aspergillus niger and microalgae (Chlorella vulgaris to form cell pellets was evaluated under different conditions, including organic carbon source (glucose; glycerol; and sodium acetate concentration; initial concentration of fungal spores and microalgal cells and light. Results showed that 2 g/L of glucose with a 1:300 ratio of fungi to microalgae provided the best culturing conditions for the process to reach >90% of cell harvest efficiency. The results also showed that an organic carbon source was required to sustain the growth of fungi and form the cell pellets. The microalgae/fungi co-cultures at mixotrophic conditions obtained much higher total biomass than pure cultures of each individual strains; indicating the symbiotic relationship between two strains. This can benefit the microbial biofuel production in terms of cell harvest and biomass production.

  18. Combined Extraction Processes of Lipid from Chlorella vulgaris Microalgae: Microwave Prior to Supercritical Carbon Dioxide Extraction

    Science.gov (United States)

    Dejoye, Céline; Vian, Maryline Abert; Lumia, Guy; Bouscarle, Christian; Charton, Frederic; Chemat, Farid

    2011-01-01

    Extraction yields and fatty acid profiles from freeze-dried Chlorella vulgaris by microwave pretreatment followed by supercritical carbon dioxide (MW-SCCO2) extraction were compared with those obtained by supercritical carbon dioxide extraction alone (SCCO2). Work performed with pressure range of 20–28 Mpa and temperature interval of 40–70 °C, gave the highest extraction yield (w/w dry weight) at 28 MPa/40 °C. MW-SCCO2 allowed to obtain the highest extraction yield (4.73%) compared to SCCO2 extraction alone (1.81%). Qualitative and quantitative analyses of microalgae oil showed that palmitic, oleic, linoleic and α-linolenic acid were the most abundant identified fatty acids. Oils obtained by MW-SCCO2 extraction had the highest concentrations of fatty acids compared to SCCO2 extraction without pretreatment. Native form, and microwave pretreated and untreated microalgae were observed by scanning electronic microscopy (SEM). SEM micrographs of pretreated microalgae present tearing wall agglomerates. After SCCO2, microwave pretreated microalgae presented several micro cracks; while native form microalgae wall was slightly damaged. PMID:22272135

  19. Combined Extraction Processes of Lipid from Chlorella vulgaris Microalgae: Microwave Prior to Supercritical Carbon Dioxide Extraction

    Directory of Open Access Journals (Sweden)

    Farid Chemat

    2011-12-01

    Full Text Available Extraction yields and fatty acid profiles from freeze-dried Chlorella vulgaris by microwave pretreatment followed by supercritical carbon dioxide (MW-SCCO2 extraction were compared with those obtained by supercritical carbon dioxide extraction alone (SCCO2. Work performed with pressure range of 20–28 Mpa and temperature interval of 40–70 °C, gave the highest extraction yield (w/w dry weight at 28 MPa/40 °C. MW-SCCO2 allowed to obtain the highest extraction yield (4.73% compared to SCCO2 extraction alone (1.81%. Qualitative and quantitative analyses of microalgae oil showed that palmitic, oleic, linoleic and α-linolenic acid were the most abundant identified fatty acids. Oils obtained by MW-SCCO2 extraction had the highest concentrations of fatty acids compared to SCCO2 extraction without pretreatment. Native form, and microwave pretreated and untreated microalgae were observed by scanning electronic microscopy (SEM. SEM micrographs of pretreated microalgae present tearing wall agglomerates. After SCCO2, microwave pretreated microalgae presented several micro cracks; while native form microalgae wall was slightly damaged.

  20. RECOVERY AND SEQUESTRATION OF CO2 FROM STATIONARY COMBUSTION SYSTEMS BY PHOTOSYNTHESIS OF MICROALGAE

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Takashi Nakamura

    2003-04-01

    Most of the anthropogenic emissions of carbon dioxide result from the combustion of fossil fuels for energy production. Photosynthesis has long been recognized as a means, at least in theory, to sequester anthropogenic carbon dioxide. Aquatic microalgae have been identified as fast growing species whose carbon fixing rates are higher than those of land-based plants by one order of magnitude. Physical Sciences Inc. (PSI), Aquasearch, and the Hawaii Natural Energy Institute at the University of Hawaii are jointly developing technologies for recovery and sequestration of CO{sub 2} from stationary combustion systems by photosynthesis of microalgae. The research is aimed primarily at demonstrating the ability of selected species of microalgae to effectively fix carbon from typical power plant exhaust gases. This report covers the reporting period 1 October to 31 December 2002 in which PSI, Aquasearch and University of Hawaii conducted their tasks. Based on the work conducted during the previous reporting period, PSI initiated work on feasibility demonstration of direct feeding of coal combustion gas to microalgae. Aquasearch continued their effort on selection and characterization of microalgae suitable for CO{sub 2} sequestration. University of Hawaii continued effort on system optimization of the CO{sub 2} sequestration system.