Thursday, August 26, 2010

Quality analysis of commercial Chlorella products used as dietary supplement in human nutrition

Quality analysis of commercial Chlorella products used as dietary supplement in human nutrition: "

Abstract
Chlorella vulgaris is one of the best-studied phototrophic eukaryotes. From the 1950s on, C. vulgaris and some other algal species were cultivated in huge quantities to meet the growing demand for alternative protein sources.
After drying, algal biomass can be merchandised as tablets, capsules, extract or powder with specific biochemical qualities.
However, the products quality, e.g. the containing species, microbial contamination or content and quality of pigments varies
enormously. In this study, commercial Chlorella products, unprocessed Chlorella powders and several production strains were investigated. Molecular analysis of the 18S rDNA confirmed either the existence
of more than one species per product or only other green algae species in about half of the samples tested. Many of the examined
samples contained critical amounts of bacterial contaminations. Furthermore, cyanobacteria were detected in some of the samples.
The content of chlorophyll a varied greatly between the samples and pheophytin, a degradation product of chlorophyll, was detected in some samples in
large concentrations. These data indicate that quality control of microalgal products is an important issue that should be
addressed by the manufactures.


  • Content Type Journal Article
  • DOI 10.1007/s10811-009-9455-4
  • Authors

    • Manuela Görs, University of Rostock Institute of Biological Sciences, Applied Ecology Albert-Einstein-Strasse 3 18051 Rostock Germany
    • Rhena Schumann, University of Rostock Institute of Biological Sciences, Applied Ecology Albert-Einstein-Strasse 3 18051 Rostock Germany
    • Dominik Hepperle, SequentiX, Digital DNA Processing Dorfstrasse 20 18249 Klein Raden Germany
    • Ulf Karsten, University of Rostock Institute of Biological Sciences, Applied Ecology Albert-Einstein-Strasse 3 18051 Rostock Germany


"
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Biofuels, facts, fantasy, and feasibility

Biofuels, facts, fantasy, and feasibility: "

Abstract It is frequently claimed that green algae are intrinsically more productive, often by orders of magnitude, than higher plants
commonly grown as crops for food. There is no firm evidence for this belief. On the contrary, there is much experience which
shows that algae are not more but less productive. Under optimal conditions, all green organisms photosynthesize at the same
rate in low light and, whilst commonly cultivated ‘sun’ species show some differences in rate in full light, these do not
translate into widely different rates of accumulation of biomass. Accordingly, irrespective of crop, one acre of land, pond
or bioreactor, can annually yield about enough biomass to fuel one motor vehicle or meet the calorific requirement of several
people. This amount of biomass is not sufficient to make other than a very small contribution to our present road transport
requirements and yet contributes significantly to global food shortages and rising prices. Reliable evidence also suggests
that, if all of the inputs are taken into account, the net energy gain of liquid biofuels, derived either from algae or terrestrial
crops, is either very modest or non-existent and will therefore bring about little or no sparing of carbon dioxide emissions.


  • Content Type Journal Article
  • DOI 10.1007/s10811-009-9446-5
  • Authors

    • David Alan Walker, University of Sheffield Sheffield UK


"
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Utilization of immobilized benthic algal species for N and P removal

Utilization of immobilized benthic algal species for N and P removal: "

Abstract Laboratory experiments were performed to study the growth rate and phosphorus (P) and nitrogen (N) uptakes of eight benthic
microalgae species isolated from different sources of pig manure. Cells immobilized in calcium alginate beads were cultured
with three replicates for each species. P removal rates obtained for the unicellular self-aggregating benthic species (Palmellopsis gelatinosa, Chlorosarcinopsis sp., and Macrochloris sp.) were markedly higher than those obtained in previous published experiments. N removal rates were highest for Macrochloris sp., Chlorosarcinopsis sp., and Euglena sp. 2 and comparable to the maximum rates obtained by other authors. Our results show an excellent efficiency of autochthonous
benthic species for nutrient removal, especially for P, and call attention to their use for wastewater treatment.


  • Content Type Journal Article
  • DOI 10.1007/s10811-009-9456-3
  • Authors

    • Carmen Pérez-Martínez, University of Granada Institute of Water Research Ramón y Cajal 4 18071 Granada Spain
    • Pedro Sánchez-Castillo, University of Granada Department of Plant Biology, Faculty of Sciences 18071 Granada Spain
    • Maria Valle Jiménez-Pérez, University of Granada Department of Plant Biology, Faculty of Sciences 18071 Granada Spain


"
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Heavy metals dynamics in seaweeds and seagrasses in Bahía Magdalena, B.C.S., México

Heavy metals dynamics in seaweeds and seagrasses in Bahía Magdalena, B.C.S., México: "

Abstract The process of metal bioaccumulation in marine food chains is poorly understood because very little data is available on metal
concentration at different trophic levels and their temporal or spatial variation. Because of that, we were interested to
(1) determine the concentration range of heavy metals in seaweed and seagrasses species in Magdalena Bay; (2) describe the
spatial and temporal variation of heavy metal concentrations in the seaweeds and seagrasses. Seasonal collections were done
at Estero Banderitas in November 2004, February, and April 2005 wherein we divided the estuary into three major areas (upper,
middle, and lower), and within each area, two sites were selected. Our results showed that iron, copper, and magnesium were
the most significant metals found in seagrasses, red, and green algae. We found significant more variation in temporal heavy
metal concentrations in relation to the maximum abundance in the samples and spatial variation in relation to the studied
taxa suggesting that hervibores have a differential intake of the metals. Also, our results suggest that heavy metals might
be incorporated regularly in the diet of many herbivorous animals with severe consequences to their health. Management strategies
for these species should consider monitoring the levels of metals.


  • Content Type Journal Article
  • DOI 10.1007/s10811-009-9457-2
  • Authors

    • R. Riosmena-Rodríguez, Universidad Autónoma de Baja California Sur Programa de Investigación en Botánica Marina, Departamento de Biología Marina La Paz Baja California Sur 23080 Mexico
    • A. Talavera-Sáenz, Universidad Autónoma de Baja California Sur Programa de Investigación en Botánica Marina, Departamento de Biología Marina La Paz Baja California Sur 23080 Mexico
    • B. Acosta-Vargas, Centro de Investigaciones Biológicas del Noroeste S.C. (CIBNOR) Mar Bermejo #195, Col. Playa Palo de Santa Rita. A.P. 128 23090 La Paz Baja California Sur Mexico
    • S. C. Gardner, Centro de Investigaciones Biológicas del Noroeste S.C. (CIBNOR) Mar Bermejo #195, Col. Playa Palo de Santa Rita. A.P. 128 23090 La Paz Baja California Sur Mexico


"
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Development of a rapid and effective method for preparing delicate dinoflagellates for scanning electron microscopy

Development of a rapid and effective method for preparing delicate dinoflagellates for scanning electron microscopy: "

Abstract We developed a rapid and effective procedure for scanning electron microscopy of three delicate dinoflagellates, Karlodinium micrum, Akashiwo sanguinea, and Heterocapsa niei. Good results were obtained when the specimens were fixed with a modified Párducz’s fixative (2% osmium tetroxide:saturated
mercuric chloride = 5:1 v/v) for 10 min, washed in 0.05 M sodium cacodylate trihydrate buffer for 2 min, dehydrated in tert-butanol for 10 min and dried with hexamethyldisilazane in air for 3 min in a fume hood because reagents are very toxic. This
method could be completed in 25 min. Compared with other preparative techniques, the present protocol has significant advantages
for SEM observation by limiting distortion of delicate specimens and reducing the preparation time.


  • Content Type Journal Article
  • DOI 10.1007/s10811-009-9461-6
  • Authors

    • Seung Won Jung, Korea Ocean Research and Development Institute South Sea Institute Geoje 656-830 Republic of Korea
    • Hyoung Min Joo, Sangmyung University Department of Life Science Seoul 110-743 Republic of Korea
    • Joon Sang Park, Sangmyung University Department of Life Science Seoul 110-743 Republic of Korea
    • Jin Hwan Lee, Sangmyung University Department of Life Science Seoul 110-743 Republic of Korea


"
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M. E. Gershwin, A. Belay (eds). Spirulina in human nutrition and health

M. E. Gershwin, A. Belay (eds). Spirulina in human nutrition and health: "

M. E. Gershwin, A. Belay (eds). Spirulina in human nutrition and health


  • Content Type Journal Article
  • DOI 10.1007/s10811-009-9467-0
  • Authors

    • Michael A. Borowitzka, Murdoch University School of Biological Sciences & Biotechnology Perth WA 6150 Australia


"
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Epiphytism of Gracilaria cliftonii (Withell, Millar & Kraft) from Western Australia

Epiphytism of Gracilaria cliftonii (Withell, Millar & Kraft) from Western Australia: "

Abstract Epiphytism in Gracilaria is a common phenomena observed in natural populations and under culture conditions. Generally, epiphytes are attached superficially
to the surface of the host however, genera such as Polysiphonia spp. and Ceramium spp. can penetrate into the host tissue affecting its growth and hence productivity. The present paper aims to identify and
quantify epiphyte abundance and characterise their attachment and penetration on the natural populations of Gracilaria cliftonii collected from Shoalwater Marine Park, Perth, Western Australia. G. cliftonii samples were collected monthly for 1 year and their epiphytes were identified. Histological studies of G. cliftonii were also performed on epiphyte attachment sites. Twenty-four species of macroalgae epiphytes were recorded, 21 belonging
to Rhodophyta and 3 to Chlorophyta. Hypnea episcopalis and Polysiphonia forfex were the dominant (p < 0.05) species during the sampling period. The maximum epiphytic load was observed in October (40%), however, the maximum
diversity of epiphytes was recorded in September and February (n = 14). Light and scanning electron microscopy studies of the epiphyte attachment sites revealed that P. forfex and Ceramium isogonum penetrated into the cortex and outer medulla of G. cliftonii, while Bryopsis plumosa and Laurencia clavata altered the cellular structure of the cell wall of G. cliftonii.


  • Content Type Journal Article
  • DOI 10.1007/s10811-009-9469-y
  • Authors

    • Julieta Muñoz, Curtin University of Technology School of Agriculture and Environmental Sciences GPO Box U1987 Perth Western Australia Australia
    • Ravi Fotedar, Curtin University of Technology School of Agriculture and Environmental Sciences GPO Box U1987 Perth Western Australia Australia


"
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Harvesting Chlorella minutissima using cell coagulants

Harvesting Chlorella minutissima using cell coagulants: "

Abstract Twelve salts were tested for their ability to coagulate microalgae cells in cultures of Chlorella minutissima. The final aim was to develop an easy and efficient approach for harvesting microalgae biomass in dense cultures. Aluminum,
ferric, and zinc salts coagulated C. minutissima cultures, while optimum concentration was 0.75 and 0.5 g L−1 for sulfate and chloride salts, respectively. Aluminum salts were most efficient, but caused some cell lysis, which may render
this approach inappropriate in some cases. Ferric and zinc salts were ranked second and third, respectively, according to
their culture cell-coagulation efficiency. Ferric salts caused a change in the color of the cells, mainly at concentrations
higher than 1 g L−1. Zinc salts were less harmful for the microalgal cells, but an additional problem was observed with cell aggregates adhering
to the walls of the glass test tubes. Selection of the appropriate coagulant is related to the purpose of the coagulation
process.


  • Content Type Journal Article
  • DOI 10.1007/s10811-009-9465-2
  • Authors

    • Aikaterini Papazi, Institute of Aquaculture Hellenic Center for Marine Research P.O. Box 2214 71003 Heraklion Crete Greece
    • Pavlos Makridis, Institute of Aquaculture Hellenic Center for Marine Research P.O. Box 2214 71003 Heraklion Crete Greece
    • Pascal Divanach, Institute of Aquaculture Hellenic Center for Marine Research P.O. Box 2214 71003 Heraklion Crete Greece


"
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Testing addition of Pseudomonas fluorescens HYK0210-SK09 to mitigate blooms of the diatom Stephanodiscus hantzschii in small- and large-scale mesocosms

Testing addition of Pseudomonas fluorescens HYK0210-SK09 to mitigate blooms of the diatom Stephanodiscus hantzschii in small- and large-scale mesocosms: "

Abstract An algicidal bacterium Pseudomonas fluorescens HYK0210-SK09 (SK09) was applied to a natural bloom of Stephanodiscus hantzschii using a small-scale mesocosm (SM) and a large-scale mesocosm (LM) to clarify the algicidal effects and evaluate the response
of the planktonic community and environments. When SK09 cells were inoculated at a final concentration of 5 × 106 cells mL−1, the abundance of S. hantzschii decreased significantly by 95% in SM and 85% in LM. The microcosm in the laboratory revealed that the abundance of Pseudomonas increased rapidly after inoculation with a corresponding decrease in the S. hantzschii population. Nutrient concentrations increased following the decline in the diatom cells. The abundances of nondominant species
such as Chlamydomonas, Cryptomonas, and Navicula increased slightly with increased nutrient concentrations. The abundance of heterotrophic protists also increased significantly
due to utilization of SK09 as food. The present study demonstrates that SK09 is an effective biocontrol agent for natural
S. hantzschii bloom, and grazing pressure plays a crucial role in the successful application of algicidal bacteria to natural environments.


  • Content Type Journal Article
  • DOI 10.1007/s10811-009-9473-2
  • Authors

    • Seung Won Jung, Korea Ocean Research and Development Institute South Sea Institute Geoje 656-830 Republic of Korea
    • Yoon-Ho Kang, Hanyang University Department of Life Science Seoul 133-791 Republic of Korea
    • Toshiya Katano, Saga University Ariake Sea Research Project Saga 840-8502 Japan
    • Baik-Ho Kim, Konkuk University Department of Environmental Science Seoul 143-701 Republic of Korea
    • Soo-Yeon Cho, Hanyang University Department of Life Science Seoul 133-791 Republic of Korea
    • Jin Hwan Lee, Sangmyung University Department of Life Science Seoul 110-743 Republic of Korea
    • Young-Ok Kim, Korea Ocean Research and Development Institute South Sea Institute Geoje 656-830 Republic of Korea
    • Myung-Soo Han, Hanyang University Department of Life Science Seoul 133-791 Republic of Korea


"
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Isolation of algicidal compounds from the red alga Corallina pilulifera against red tide microalgae

Isolation of algicidal compounds from the red alga Corallina pilulifera against red tide microalgae: "

Abstract We determined the structure of two compounds, namely, 5,8,11,14,17-eicosapentaenoic acid (EPA) and di-n-octylphthalate (DnOP), which have algicidal activity against the toxic dinoflagellate, Cochlodinium polykrikoides. The polyunsaturated fatty acid EPA and the anthropogenic DnOP were isolated from the MeOH extract of the red alga Corallina pilulifera. We also found that a commercial EPA has algicidal activity identical to that of the EPA purified from C. pilulifera. At low inoculum (5.0 × 102 cells mL−1), the highest algicidal activity of a commercial EPA exhibited approximately 92.6% algicidal activity after 1 h and 96.8%
after 6 h treatment at 6 µg mL−1, respectively. At high inoculum (1.0 × 104 cells mL−1), the strongest algicidal activity of EPA showed 69.5% after 1 h and 75.5% algicidal activity after 6 h treatment at 6 µg
mL−1, respectively. However, EPA did not show algicidal activity against several microalgae used in aquaculture such as Pavlova lutheri, Tetraselmis suecica, Isochrysis galbana, and Nannochloris oculata for 6 h treatment at 6 µg mL−1. The algicidal activity of the five red tide strains to EPA (3 µg mL−1) showed about 86.6%, 86.6%, and 67.3% algicidal activity against Skeletonema costatum, Chaetoceros curvisetus, and C. polykrikoides after 1 h treatment at low inoculum (5.0 × 102 cells mL−1), respectively, but not against Prorocentrum minimum and Scrippsiella trochoidea. We concluded that EPA might be useful as a controlling agent of harmful algal blooms.


  • Content Type Journal Article
  • DOI 10.1007/s10811-009-9478-x
  • Authors

    • Mi-Young Oh, Kangnung-Wonju National University Faculty of Marine Bioscience and Technology Gangneung 210-702 South Korea
    • Sang Beum Lee, Kangnung-Wonju National University Faculty of Marine Bioscience and Technology Gangneung 210-702 South Korea
    • Deuk-Hee Jin, Kangnung-Wonju National University Faculty of Marine Bioscience and Technology Gangneung 210-702 South Korea
    • Yong-Ki Hong, Pukyong National University Department of Biotechnology Busan 608-737 South Korea
    • Hyung-Joo Jin, Kangnung-Wonju National University Faculty of Marine Bioscience and Technology Gangneung 210-702 South Korea


"
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Seasonal changes in proteomic profiles of Japanese kelp: Saccharina japonica (Laminariales, Phaeophyceae)

Seasonal changes in proteomic profiles of Japanese kelp: Saccharina japonica (Laminariales, Phaeophyceae): "

Abstract The seasonal variation in protein expression in the sporophyte of Saccharina japonica (Areschoug) Lane, Mays, Druehl and Saunders was investigated. High-quality proteins that are available for protein profiling
were extracted by the ethanol/phenol extraction method, and 564 protein spots in total were detected. Proteins were identified
through database search by combining Mascot and MS BLAST for 100 spots, and significant difference of expression level between
the samples collected in winter and in summer was observed in the case of 95 spots. Within 67 spots upregulated in the samples
collected in summer, vanadium-dependent bromoperoxidase (vBPO) were identified for 21spots. It is thought that the elevation
of expression level of vBPO in summer depend on the activation of the functions: (1) elimination of active oxygen species
and protection of the algal body from oxygen injury, (2) prevention of the growth inhibition due to the adherence of attached
organisms, in the season.


  • Content Type Journal Article
  • DOI 10.1007/s10811-009-9477-y
  • Authors

    • Norishige Yotsukura, Hokkaido University Field Science Center for Northern Biosphere Sapporo Hokkaido 060-0809 Japan
    • Kouhei Nagai, St. Marianna University School of Medicine Kawasaki Kanagawa 216-8514 Japan
    • Hajime Kimura, Fisheries Experimental Station Kushimoto Wakayama 649-3503 Japan
    • Kouichi Morimoto, Kinki University Department of Biotechnological Science Kinokawa Wakayama 649-6493 Japan


"
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Anti-cyanobacterial activity of Moringa oleifera seeds

Anti-cyanobacterial activity of Moringa oleifera seeds: "

Abstract Filtrates from crushed Moringa oleifera seeds were tested for their effects on growth and Photosystem II efficiency of the common bloom-forming cyanobacterium Microcystis aeruginosa. M. aeruginosa populations exhibited good growth in controls and treatments with 4- and 8-mg crushed Moringa seeds per liter, having similar growth rates of 0.50 (±0.01) per day. In exposures of 20- to 160-mg crushed Moringa seeds L−1, growth rates were negative and on average −0.23 (±0.05) .day−1. Presumably, in the higher doses of 20- to 160-mg crushed seeds per liter, the cyanobacteria died, which was supported by
a rapid drop in the Photosystem II efficiency (ΦPSII), while the ΦPSII was high and unaffected in 0, 4, and 8 mg L−1. High-density populations of M. aeruginosa (chlorophyll-a concentrations of ∼270 µg L−1) were reduced to very low levels within 2 weeks of exposure to ≥80-mg crushed seeds per liter. At the highest dosage of 160 mg L−1, the ΦPSII dropped to zero rapidly and remained nil during the course of the experiment (14 days). Hence, under laboratory conditions,
a complete wipeout of the bloom could be achieved. This is the first study that yielded evidence for cyanobactericidal activity
of filtrate from crushed Moringa seeds, suggesting that Moringa seed extracts might have a potential as an effect-oriented measure lessening cyanobacterial nuisance.


  • Content Type Journal Article
  • DOI 10.1007/s10811-009-9485-y
  • Authors

    • Miquel Lürling, Wageningen University Aquatic Ecology & Water Quality Management Group, Department of Environmental Sciences P.O. Box 47 6700 AA Wageningen the Netherlands
    • Wendy Beekman, Wageningen University Aquatic Ecology & Water Quality Management Group, Department of Environmental Sciences P.O. Box 47 6700 AA Wageningen the Netherlands


"
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Flocculation of microalgae using cationic starch

Flocculation of microalgae using cationic starch: "

Abstract Due to their small size and low concentration in the culture medium, cost-efficient harvesting of microalgae is a major challenge.
We evaluated the potential of cationic starch as a flocculant for harvesting microalgae using jar test experiments. Cationic
starch was an efficient flocculant for freshwater (Parachlorella, Scenedesmus) but not for marine microalgae (Phaeodactylum, Nannochloropsis). At high cationic starch doses, dispersion restabilization was observed. The required cationic starch dose to induce flocculation
increased linearly with the initial algal biomass concentration. Of the two commercial cationic starch flocculants tested,
Greenfloc 120 (used in wastewater treatment) was more efficient than Cargill C*Bond HR 35.849 (used in paper manufacturing).
For flocculation of Parachlorella using Greenfloc 120, the cationic starch to algal biomass ratio required to flocculate 80% of algal biomass was 0.1. For
Scenedesmus, a lower dose was required (ratio 0.03). Flocculation of Parachlorella using Greenfloc 120 was independent of pH in the pH range of 5 to 10. Measurements of the maximum quantum yield of PSII suggest
that Greenfloc 120 cationic starch was not toxic to Parachlorella. Cationic starch may be used as an efficient, nontoxic, cost-effective, and widely available flocculant for harvesting microalgal
biomass.


  • Content Type Journal Article
  • DOI 10.1007/s10811-009-9488-8
  • Authors

    • Dries Vandamme, K.U.Leuven Campus Kortrijk Laboratory Aquatic Biology E. Sabbelaan 53 8500 Kortrijk Belgium
    • Imogen Foubert, K.U.Leuven Campus Kortrijk Laboratory Aquatic Biology E. Sabbelaan 53 8500 Kortrijk Belgium
    • Boudewijn Meesschaert, Katholieke Hogeschool Brugge-Oostende Department of Industrial Sciences and Technology Zeedijk 101 8400 Oostende Belgium
    • Koenraad Muylaert, K.U.Leuven Campus Kortrijk Laboratory Aquatic Biology E. Sabbelaan 53 8500 Kortrijk Belgium


"
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Improved methods of analysis for betaines in Ascophyllum nodosum and its commercial seaweed extracts

Improved methods of analysis for betaines in Ascophyllum nodosum and its commercial seaweed extracts: "

Abstract Beneficial effects of seaweeds and their extracts on crop performance have been attributed to a variety of compounds, including
the betaines which are quaternary ammonium betaines. Methods of analysis of betaines published thus far suffer from low sensitivity,
lack of baseline separation of individual betaines and from interference from other sample constituents. A rapid cleanup protocol
and a sensitive LC-MS/MS method of analysis were developed to afford baseline separation of four betaines in the brown alga
Ascophyllum nodosum and its commercial seaweed extract. Using this method, the presence of glycine betaine, δ-aminovaleric acid betaine, γ-aminobutyric
acid betaine and laminine in A. nodosum, and commercial extracts derived from A. nodosum, were confirmed and quantified. The major betaine present was γ-aminobutyric acid betaine accounting for 0.008–0.014% of
the dry weight of the seaweed and 0.014–0.027% of the dry weight of the commercial extracts. Seasonal variation in betaine
content was observed. Differences in the total betaine content were observed between A. nodosum of the yellow (0.011–0.017% dry weight) and the olive green (0.017–0.021% dry weight) coloured morphologies.


  • Content Type Journal Article
  • DOI 10.1007/s10811-009-9483-0
  • Authors

    • Shawna L. MacKinnon, National Research Council of Canada Institute for Marine Biosciences 1411 Oxford Street Halifax NS Canada B3H 3Z1
    • David Hiltz, Acadian Seaplants Limited 30 Brown Ave. Dartmouth NS Canada B3B 1X8
    • Raul Ugarte, Acadian Seaplants Limited 30 Brown Ave. Dartmouth NS Canada B3B 1X8
    • Cheryl A. Craft, National Research Council of Canada Institute for Marine Biosciences 1411 Oxford Street Halifax NS Canada B3H 3Z1


"
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Management of natural Ulva spp. blooms in San Quintin Bay, Baja California: Is it justified?

Management of natural Ulva spp. blooms in San Quintin Bay, Baja California: Is it justified?: "

Abstract According to Zertuche-González et al. (2009), Ulva spp. blooms, favored by oyster cultivation, are likely displacing subtidal meadows of Zostera marina in San Quintin Bay, Baja California. The authors propose a partial removal of the seaweed to reduce the risk of eutrophication
and eelgrass displacement in the bay. We warn about the removal of Ulva spp. biomass by raising six arguments that emphasize the necessity of a historical and ecosystem-based management for San
Quintin Bay. First, processes other than competitive exclusion by Ulva spp. blooms more likely explain changes of Z. marina subtidal meadows in the past decade. Second, there is no consistent evidence that oyster cultivation is promoting blooms
of Ulva spp. and the loss of eelgrass. Third, the removal of Ulva spp. biomass is based on experiences of heavily anthropogenically eutrophic systems, while San Quintin Bay is not. Fourth,
the proposed course of actions to restore eelgrass meadows ignores general historical baselines of estuarine and coastal systems
by confusing what it means to be “pristine.” Fifth, despite the important experimental evidence indicating strong top–down
control in temperate seagrass meadows, Zertuche-González et al. (2009) underestimated the capacity of consumers in structuring dynamics of vegetated soft-bottom communities in San Quintin Bay.
Sixth, Ulva expansa may exert positive effects on seagrass ecosystem properties and functions. Instead, we propose protection against the propagation
of unsustainable practices in the bay, and the reintroduction of large consumers that are now absent in this ecosystem. An
ecosystem-based analysis of the role of Ulva spp. on eelgrass dynamics is needed.


  • Content Type Journal Article
  • DOI 10.1007/s10811-009-9491-0
  • Authors

    • Pablo Jorgensen, El Colegio de la Frontera Sur (ECOSUR) Km 5.5 Ave. del Centenario Chetumal Quintana Roo C.P. 77014 Mexico
    • Silvia E. Ibarra-Obando, CICESE Carretera Ensenada-Tijuana no. 3918, Zona Playitas Ensenada Baja California C.P. 22860 Mexico
    • José D. Carriquiry, Universidad Autónoma de Baja Calfornia Instituto de Investigaciones Oceanológicas Apdo. Postal # 453 Ensenada Baja California C.P. 22860 Mexico


"
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Biochemical characterization of carotenoids in two species of Trentepohlia (Trentepohliales, Chlorophyta)

Biochemical characterization of carotenoids in two species of Trentepohlia (Trentepohliales, Chlorophyta): "

Abstract Two species of Trentepohlia, i.e., Trentepohlia aurea and Trentepohlia cucullata were collected from walls and tree bark, respectively, at two different seasons in a year. The total carotenoid content in
both the species is very high during winter but decreases significantly during summer. By spectroscopic analysis, it was found
that. T. aurea and T. cucullata growing in natural habitats are rich sources of carotenoids. The individual carotenoids were separated, identified, and estimated
by HPLC, and identified as β-carotene along with some other carotenoids, i.e., neoxanthin, lutein, β-cryptoxanthin, β,γ-carotene,
β,ε-carotene (absent during summer).


  • Content Type Journal Article
  • DOI 10.1007/s10811-009-9495-9
  • Authors

    • Rumila Mukherjee, Gauhati University Department of Chemistry Guwahati 781014 Assam India
    • Shailen P. Borah, Gauhati University Department of Botany Guwahati 781014 Assam India
    • Bhabesh C. Goswami, Gauhati University Department of Chemistry Guwahati 781014 Assam India


"
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Growth and toxin production of tropical Alexandrium minutum Halim (Dinophyceae) under various nitrogen to phosphorus ratios

Growth and toxin production of tropical Alexandrium minutum Halim (Dinophyceae) under various nitrogen to phosphorus ratios: "

Abstract Effects of nitrogen to phosphorous (N/P) ratios of two nitrogen sources (nitrate and ammonium) on growth and toxin production
of a tropical estuarine dinoflagellate, Alexandrium minutum Halim, were examined using a strain isolated from a bloom at Tumpat Estuary, Malaysia in September 2001. Experiments were
carried out in batch cultures, using either nitrate (N-NO3) or ammonium (N-NH4) as the nitrogen source at a constant amount, and with initial N/P ratios ranging from 5 to 500. Cell density, residual N
and P in the medium, cellular toxin quota (Q
t), and toxin composition were analyzed throughout the growths. Our results showed that cell densities and growth rates of
A. minutum were severely suppressed under high N/P ratios (>100) in both N-NO3 and N-NH4 treatments. Cells tended to be larger at lower growth rate and P-limited cultures. Toxin profile was relatively constant
throughout the experiments, with GTX4/GTX1 as the dominant toxin congeners. Cellular toxin quota (Q
t) increased with elevated N/P ratios in both N-NO3 and N-NH4 treatments. Toxin production rate, R
tox, however was enhanced in N-NH4-grown cultures when P was limited, but showed no difference between N-NO3- and N-NH4-grown cultures when P was replete. Our results clearly showed that N/P ratios as well as the nitrogen compounds not only
affected the growth of A. minutum, but also the cellular toxin quota and its toxin production rate.


  • Content Type Journal Article
  • DOI 10.1007/s10811-009-9443-8
  • Authors

    • Po-Teen Lim, Universiti Malaysia Sarawak Faculty of Resource Science and Technology Kota Samarahan Sarawak 94300 Malaysia
    • Chui-Pin Leaw, Universiti Malaysia Sarawak Institute of Biodiversity and Environmental Conservation Kota Samarahan Sarawak 94300 Malaysia
    • Atsushi Kobiyama, Kitasato University School of Fisheries Science Sanriku Ofunato Iwate 022-0101 Japan
    • Takehiko Ogata, Kitasato University School of Fisheries Science Sanriku Ofunato Iwate 022-0101 Japan


"
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Development of expressed sequence tag-derived microsatellite markers for Saccharina (Laminaria) japonica

Development of expressed sequence tag-derived microsatellite markers for Saccharina (Laminaria) japonica: "

Abstract Expressed sequence tag-derived microsatellite markers (EST-SSR) were generated and characterized in Laminaria japonica using data mining from updated public EST databases and polymorphism testing. Fifty-eight of 578 ESTs (10.0%) containing
various repeat motifs were used to design polymerase chain reaction (PCR) amplification primers. A total of 12 pairs of primer
were generated and used in the PCR amplification. Alleles per locus ranged from two to ten (average of 5.7). The observed
heterozygosities and expected heterozygosities were from 0.045 to 0.543 and from 0.056 to 0.814, respectively. All loci were
in Hardy–Weinberg equilibrium and no linkage disequilibrium was detected. These robust, informative, and potentially transferable
polymorphic markers appear suitable for population, genetic, parentage, and mapping studies of L. japonica.


  • Content Type Journal Article
  • DOI 10.1007/s10811-009-9426-9
  • Authors

    • Fuli Liu, Chinese Academy of Sciences Institute of Oceanology Qingdao 266071 China
    • Xiuliang Wang, Chinese Academy of Sciences Institute of Oceanology Qingdao 266071 China
    • Jianting Yao, Chinese Academy of Sciences Institute of Oceanology Qingdao 266071 China
    • Wandong Fu, Chinese Academy of Sciences Institute of Oceanology Qingdao 266071 China
    • Delin Duan, Chinese Academy of Sciences Institute of Oceanology Qingdao 266071 China


"
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Isolation of C-phycocyanin from Synechococcus sp., (Anacystis nidulans BD1)

Isolation of C-phycocyanin from Synechococcus sp., (Anacystis nidulans BD1): "

Abstract We report a procedure for obtaining fairly pure phycocyanin from a local isolate of the cyanobacterium Synechococcus sp (Anacystis nidulans BD1). Cells were incubated with 1 mg∙mL−1 of lysozyme at 37°C for 16 h with shaking. The cell-free extract was treated with activated charcoal and chitosan. The purity
(A
620/280) of phycocyanin obtained after lysozyme treatment was up to 2.18, which could be improved to 4.72 after incubation with activated
charcoal and chitosan. The yield of phycocyanin was 80–100 mg∙g−1 dry weight of cells. The method reported here is a single-step and efficient procedure and has the potential to be adopted
for large-scale production of phycocyanin.


  • Content Type Journal Article
  • DOI 10.1007/s10811-009-9449-2
  • Authors

    • Alka Gupta, Bhabha Atomic Research Centre Molecular Biology Division Mumbai 400 085 India
    • Jayashree K. Sainis, Bhabha Atomic Research Centre Molecular Biology Division Mumbai 400 085 India


"
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Identification of a glucose-6-phosphate isomerase involved in adaptation to salt stress of Dunaliella salina

Identification of a glucose-6-phosphate isomerase involved in adaptation to salt stress of Dunaliella salina: "

Abstract The unicellular green alga Dunaliella salina is a recognized model for studying plant adaptation to high salinity. To isolate some salt-induced proteins at proteomics
levels and to identify their expressions at gene levels, algal cells at logarithmic phase cultured in 1.5 and 3.5 M NaCl media
were harvested for protein extraction. Solubilized proteins were applied to two-dimensional gel electrophoresis (2-DE) and
analyzed by ImageMaster 2D Platinum software. Twenty-one protein spots whose intensities were elevated threefold to 13-fold
at 3.5 M NaCl as compared to 1.5 M NaCl were analyzed by matrix-assisted laser desorption/ionization tandem time of flight
mass spectrometry. One salt-induced protein isolated from the 2-DE gels was identified as a glucose-6-phosphate isomerase
(GPI) from D. salina (DsGPI). A full-length cDNA of DsGPI was obtained using rapid amplification of cDNA end technique, and it was shown by heterologous
expression to encode a protein with a molecular weight consistent with the protein spot in the 2-DE gels. Real-time quantitative
RT-PCR demonstrated that the mRNA of DsGPI was induced up to eightfold (P < 0.01) by 2.5 M and 14-fold higher (P < 0.01) by 3.5 M NaCl than by 1.5 M NaCl, respectively. It is concluded that the protein isolated through 2-DE is indeed
DsGPI and that the DsGPI gene may be involved in adaptation to high salinity.


  • Content Type Journal Article
  • DOI 10.1007/s10811-009-9494-x
  • Authors

    • Liuqing Cui, Zhengzhou University Institute of Tumor Molecular Surgery, The First Affiliated Hospital 40 Daxue Road Zhengzhou 450052 China
    • Yurong Chai, Zhengzhou University College of Basic Medicine 100 Kexue Avenue Zhengzhou 450001 China
    • Jie Li, Zhengzhou University Laboratory for Cell Biology, Department of Biology 100 Kexue Avenue Zhengzhou 450001 China
    • Hongtao Liu, Zhengzhou University Laboratory for Cell Biology, Department of Biology 100 Kexue Avenue Zhengzhou 450001 China
    • Lei Zhang, Zhengzhou University Laboratory for Cell Biology, Department of Biology 100 Kexue Avenue Zhengzhou 450001 China
    • Lexun Xue, Zhengzhou University Institute of Tumor Molecular Surgery, The First Affiliated Hospital 40 Daxue Road Zhengzhou 450052 China


"
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Photosynthetic activity of benthic diatoms in response to different temperatures

Photosynthetic activity of benthic diatoms in response to different temperatures: "

Abstract The photosynthetic activities of benthic diatoms in response to temperature changes were assessed by measuring chlorophyll
fluorescence kinetics. Small benthic diatom species with large surface area to volume (SA/V) ratios responded to increasing temperature differently from large diatoms, since larger ratios caused lower photosynthetic
activity under high-temperature conditions. The small SA/V ratios of large cells may be advantageous in benthic environments under adverse conditions such as high temperature and/or
strong light. A size-dependent differential response of benthic diatoms to changes in environmental factors such as temperature
may result in an altered distribution of the different diatom communities.


  • Content Type Journal Article
  • DOI 10.1007/s10811-009-9493-y
  • Authors

    • Mi Sun Yun, Korea Polar Research Institute Division of Polar Biology & Ocean Science Songdo Techno Park, 7-50, Songdo-dong, Yeonsu-gu Incheon 406-840 Korea
    • Sang Heon Lee, Korea Polar Research Institute Division of Polar Biology & Ocean Science Songdo Techno Park, 7-50, Songdo-dong, Yeonsu-gu Incheon 406-840 Korea
    • Ik Kyo Chung, Pusan National University Division of Earth Environmental System 30, Jangjeon-dong, Geumjeong-gu Busan 609-735 Korea


"
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Application of SSR and AFLP to the analysis of genetic diversity in Gracilariopsis lemaneiformis (Rhodophyta)

Application of SSR and AFLP to the analysis of genetic diversity in Gracilariopsis lemaneiformis (Rhodophyta): "

Abstract The agarophyte Gracilariopsis lemaneiformis is both important for biological research and of significant economic value. However, the genetic diversity of wild populations
of the alga has not been studied. We used amplified fragment length polymorphism (AFLP) PCR and simple sequence repeat (SSR)
analysis to investigate diversity in four field populations, three from the coast of Qingdao and one from Weihai, China. Forty
G. lemaneiformis isolates collected from the four different geographical groups were analyzed using 16 pairs of SSR primers for PCR amplification.
However, no polymorphisms were detected, indicative of a degree of genetic homogeneity. A total of 347 reproducible bands
were then amplified using eight AFLP primer pairs, and genetic indices of diversity within and between populations were calculated.
This analysis revealed only low levels of genetic diversity both within and between the four geographical groups of G. lemaneiformis. The Weihai population showed a higher within-population genetic diversity than any of the Qingdao populations. The data
suggest that there is only limited gene flow between populations. An UPGMA dendrogram revealed two main clusters, and one
of these included all the Qingdao isolates. The order of clustering was in accordance with their geographical distribution.
These results suggest that the wild G. lemaneiformis populations are closely related and that there is little genetic diversity within wild germplasm in the regions sampled.


  • Content Type Journal Article
  • DOI 10.1007/s10811-009-9500-3
  • Authors

    • Qiaoqiao Pang, Ocean University of China Key Laboratory of Marine Genetics and Breeding, Ministry of Education Qingdao 266003 People’s Republic of China
    • Zhenghong Sui, Ocean University of China Key Laboratory of Marine Genetics and Breeding, Ministry of Education Qingdao 266003 People’s Republic of China
    • Kyoung Ho Kang, Chonnam National University Department of Aquaculture Yeosu 550-749 Jeonnam South Korea
    • Fanna Kong, Ocean University of China Key Laboratory of Marine Genetics and Breeding, Ministry of Education Qingdao 266003 People’s Republic of China
    • Xuecheng Zhang, Ocean University of China Key Laboratory of Marine Genetics and Breeding, Ministry of Education Qingdao 266003 People’s Republic of China


"
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Evaluation of the toxicity of Arthrospira (Spirulina) platensis extract

Evaluation of the toxicity of Arthrospira (Spirulina) platensis extract: "

Abstract In this study, the methanol extract of Arthrospira (Spirulina) platensis was examined for acute and subchronic toxicities. The extract did not produce any sign of toxicity within 7 days after feeding
it at a single high dose of 6 g kg−1 body weight to female and male Swiss mice. For the subchronic toxicity test, the extract at doses of 6, 12, and 24 mg kg−1 body weight was orally administered to six male and six female Wistar rats daily for 12 weeks. Throughout the study period,
we did not observe any abnormalities on behavior, food and water intakes, and health status among the treated animals. The
hematology and clinical chemistry parameters of treated groups did not significantly differ from those of the controls in
both sexes. Postmortem examination of the test groups also showed no abnormalities in both gross and histological findings.
These results thus suggest that the methanol extract of A. platensis did not cause acute or subchronic toxicity in our experimental animals.


  • Content Type Journal Article
  • DOI 10.1007/s10811-009-9499-5
  • Authors

    • Nongporn Hutadilok-Towatana, Prince of Songkla University Department of Biochemistry, Faculty of Science Hat Yai 90110 Thailand
    • Wantana Reanmongkol, Prince of Songkla University Department of Clinical Pharmacy, Faculty of Pharmaceutical Sciences Hat Yai Thailand
    • Pharkphoom Panichayupakaranant, Prince of Songkla University Department of Pharmacognosy and Pharmaceutical Botany, Faculty of Pharmaceutical Sciences Hat Yai Thailand


"
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Carotenoid fluorescence in Dunaliella salina

Carotenoid fluorescence in Dunaliella salina: "

Abstract

Dunaliella salina is a halotolerant green alga that is well known for its carotenoid producing capacity. The produced carotenoids are mainly
stored in lipid globules. For various research purposes, such as production and extraction kinetics, we would like to determine
and/or localise the carotenoid globules in vivo. In this study, we show that the carotenoid-rich globules emit clear green
fluorescence, which can be used in, for example, fluorescence microscopy (e.g. CLSM) to obtain pictures of the cells and their
carotenoid content.


  • Content Type Journal Article
  • DOI 10.1007/s10811-010-9505-y
  • Authors

    • Dorinde M. M. Kleinegris, Wageningen University and Research Centre Agrotechnology and Food Science, Bioprocess Engineering P.O. Box 8129 6700 EV Wageningen The Netherlands
    • Marjon A. van Es, Wageningen University and Research Centre Agrotechnology and Food Science, Bioprocess Engineering P.O. Box 8129 6700 EV Wageningen The Netherlands
    • Marcel Janssen, Wageningen University and Research Centre Agrotechnology and Food Science, Bioprocess Engineering P.O. Box 8129 6700 EV Wageningen The Netherlands
    • Willem A. Brandenburg, Wageningen University and Research Centre Plant Research International BV, Agrosystems Research P.O. Box 16 6700 AV Wageningen The Netherlands
    • René H. Wijffels, Wageningen University and Research Centre Agrotechnology and Food Science, Bioprocess Engineering P.O. Box 8129 6700 EV Wageningen The Netherlands


"
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Preparation of superior quality products from two Indian agarophytes

Preparation of superior quality products from two Indian agarophytes: "

Abstract
The effect of alkali pre-treatments on the properties of agar obtained from Gelidiella acerosa and Gelidium pusillum growing along the West and South coast of India was studied in order to evaluate its potential for industrial use. Agar samples
were extracted by hot water extraction and termed native agar, and alkali pre-treatment was carried out with various NaOH
concentrations e.g. 4%, 6%, 8%, 10% and 15%, to optimise the alkali concentration for preparation of alkali-treated agar.
Gelidiella acerosa and Gelidium pusillum produced superior quality agar polymers having greater gel strengths 2,000 ± 50 and 1,400 ± 50 g cm−2 and lower sulphate contents ≤0.30% and ≤0.50%, respectively, as opposed the low gel strength and high sulphate content agars
reported in the literature. Furthermore, the physicochemical properties of agars were identical with the commercially available
agars. The results of this study revealed that Indian agarophytes may be used for production of superior quality agar and
agaroses, which may be used for food and biological applications.


  • Content Type Journal Article
  • DOI 10.1007/s10811-010-9523-9
  • Authors

    • Ramavatar Meena, Council of Scientific Industrial & Research, India Marine Biotechnology and Ecology Discipline, Central Salt & Marine Chemicals Research Institute G. B. Marg Bhavnagar 364 002 Gujarat India
    • Kamalesh Prasad, Council of Scientific Industrial & Research, India Marine Biotechnology and Ecology Discipline, Central Salt & Marine Chemicals Research Institute G. B. Marg Bhavnagar 364 002 Gujarat India
    • A. K. Siddhanta, Council of Scientific Industrial & Research, India Marine Biotechnology and Ecology Discipline, Central Salt & Marine Chemicals Research Institute G. B. Marg Bhavnagar 364 002 Gujarat India


"
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A fast algal bioassay for assessment of copper toxicity in water using Euglena gracilis

A fast algal bioassay for assessment of copper toxicity in water using Euglena gracilis: "

Abstract
A rapid, sensitive algal bioassay was investigated to monitor copper toxicity using photosynthetic activity and motility parameters
as end points in the photosynthetic flagellate Euglena gracilis. Effects on motility parameters were determined using the automatic bioassay ECOTOX. Photosynthetic efficiency was measured
using chlorophyll fluorescence by means of a fast, noninvasive pulse amplitude modulated fluorometer. These parameters were
assessed regarding their effectiveness as end points for short- (0–24 h) and long-term (1–5 days) toxicity tests. The model
organism showed significant responses to the tested concentrations at both motility and photosynthesis examined levels. EC50 values for movement parameters immediately after the cells were mixed with copper are 19.09 (300.4 μM), 20.4 (312 μM) and
23.09 (363.35 μM) mg L−1 for motility, r-value and velocity, respectively. The current study proofs that Euglena is a convenient biotest organism where motility parameters show rapid sensitive responses to copper (direct exposure to copper).
Also, the photosynthetic parameters appear to be appropriate for acute and chronic toxicity tests for higher and lower copper
concentrations, respectively.


  • Content Type Journal Article
  • DOI 10.1007/s10811-010-9520-z
  • Authors

    • Hoda Ahmed, Friedrich-Alexander Universität Department für Biologie Staudtstr. 5 91058 Erlangen Germany
    • Donat-Peter Häder, Friedrich-Alexander Universität Department für Biologie Staudtstr. 5 91058 Erlangen Germany


"
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Analysis of interspecific variation in relative fatty acid composition: use of flow cytometry to estimate unsaturation index and relative polyunsaturated fatty acid content in microalgae

Analysis of interspecific variation in relative fatty acid composition: use of flow cytometry to estimate unsaturation index and relative polyunsaturated fatty acid content in microalgae: "

Abstract
Relative polyunsaturated fatty acid content and unsaturation index are very important composition variables in the use of
microalgae both for animal and human nutrition and biofuel production. A readily available technique to rapidly and inexpensively
estimate relative fatty acid composition is very important for mass screening of new strains for the production of different
types of oil. This study demonstrates the validity of Nile Red staining and flow cytometry for quick estimation of unsaturation
index and relative fatty acid content in microalgae. Nile Red staining allows polar and neutral lipid contents to be estimated,
and in this study a significant correlation was observed between polar/neutral ratio and fatty acid content in the species
studied, corresponding to higher polyunsaturated fatty acid content in the polar lipid fraction of microalgae. This technique
enables quick estimation of relative polyunsaturated fatty acid content and interspecific variation, as well as variations
caused by culture conditions. In the species studied, most variability in fatty acid composition was due to variation in monounsaturated
and polyunsaturated fatty acids, with less variation observed in saturated fatty acid content.


  • Content Type Journal Article
  • DOI 10.1007/s10811-010-9526-6
  • Authors

    • Héctor Mendoza Guzmán, Instituto Tecnológico de Canarias Department of Biotechnology Pozo Izquierdo s/n (35119) Santa Lucía de Tirajana Las Palmas Spain
    • Adelina de la Jara Valido, Instituto Tecnológico de Canarias Department of Biotechnology Pozo Izquierdo s/n (35119) Santa Lucía de Tirajana Las Palmas Spain
    • Laura Carmona Duarte, Instituto Tecnológico de Canarias Department of Biotechnology Pozo Izquierdo s/n (35119) Santa Lucía de Tirajana Las Palmas Spain
    • Karen Freijanes Presmanes, Instituto Tecnológico de Canarias Department of Biotechnology Pozo Izquierdo s/n (35119) Santa Lucía de Tirajana Las Palmas Spain


"
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A decade of change in the seaweed hydrocolloids industry

A decade of change in the seaweed hydrocolloids industry: "

Abstract
Seaweed hydrocolloid markets continue to grow, but instead of the 3–5% achieved in the 1980s and 1990s, the growth rate has
fallen to 1–3% per year. This growth has been largely driven by emerging markets in China, Eastern Europe, Brazil, etc. Sales
of agar, alginates and carrageenans in the US and Europe are holding up reasonably well in spite of the recession. However,
price increases to offset costs in 2008 and 2009 have begun to have a dampening effect on sales, especially in markets where
substitution or extension with less expensive ingredients is possible. These higher prices have been driven by higher energy,
chemicals and seaweed costs. The higher seaweed costs reflect seaweed shortages, particularly for carrageenan-bearing seaweeds.
The Philippines and Indonesia are the dominant producers of the farmed Kappaphycus and Eucheuma species upon which the carrageenan industry depends and both countries are experiencing factors limiting seaweed production.
Similar tightening of seaweed supplies are beginning to show up in brown seaweeds used for extracting alginates, and in the
red seaweeds for extracting agar. The structure of the industry is also undergoing change. Producers in China are getting
stronger, and while they have not yet developed the marketing skills to compete effectively in the developed world markets,
they have captured much of their home market. China does not produce the red and brown seaweeds needed for higher end food
hydrocolloid production. Stocking their factories with raw material has led to the supply problems. Sales growth continues
to suffer from few new product development successes in recent years; although some health care applications are showing some
promise, i.e., carrageenan gel capsules and alginate micro-beads.


  • Content Type Journal Article
  • DOI 10.1007/s10811-010-9529-3
  • Authors

    • Harris J. Bixler, Ingredients Solutions, Inc 631 Moosehead Trail Waldo ME 04915 USA
    • Hans Porse, 2InterColloids Rodtjornevej 37 2720 Vanlose Denmark


"
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Extraction and characterisation of alginate from brown seaweeds (Fucales, Phaeophyceae) collected from Port Dickson, Peninsular Malaysia

Extraction and characterisation of alginate from brown seaweeds (Fucales, Phaeophyceae) collected from Port Dickson, Peninsular Malaysia: "

Abstract
Four species of brown seaweeds, namely Sargassum baccularia, Sargassum binderi, Sargassum siliquosum and Turbinaria conoides, harvested from Port Dickson, Negeri Sembilan, Malaysia were analysed for ash content, alginate yield and alginate properties.
Seaweeds calcined at 450°C were found to have low amount of non-combustible residue as these were not contaminated by calcareous
animals. Alginate was extracted from these seaweeds by two methods: hot and cold. In the hot method, the storing time was
3 h and the processing temperature was 50°C, whilst in the cold method, the sample was stored overnight at room temperature.
Higher yield of alginate was obtained by the hot method compared to the cold method, but alginate extracted by the cold method
gave higher molecular weight. In the hot method, 49.9% of alginate was extracted from S. siliquosum, followed by T. conoides (41.4%), S. binderi (38.9%) and S. baccularia (26.7%). Alginate extracted from T. conoides has an average molecular weight, M
w, of 8.06 × 105 g mol−1, whereas alginate from S. siliquosum was the lowest in M
w (4.81 × 105 g mol−1) when the extraction was done at room temperature. Alginate extracted from S. baccularia was found to be very heat-sensitive. Its M
w has dropped more than 83%, from 7.52 × 105 to 1.23 × 105 g mol−1, when the extraction temperature was raised. The effect of heat on the extent of depolymerisation of the alginate molecule
of the other three brown seaweed species was less significant, with decrease in molecular weight ranging between 13% and 16%.


  • Content Type Journal Article
  • DOI 10.1007/s10811-010-9533-7
  • Authors

    • Swee-Yong Chee, Jalan Universiti Faculty of Science, Universiti Tunku Abdul Rahman Bandar Barat 31900 Kampar Perak Malaysia
    • Ping-Keong Wong, Jalan Universiti Faculty of Science, Universiti Tunku Abdul Rahman Bandar Barat 31900 Kampar Perak Malaysia
    • Ching-Lee Wong, Universiti Tunku Abdul Rahman Department of Science, Faculty of Engineering and Science Jalan Genting Kelang 53300 Kuala Lumpur Malaysia


"
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“Green water” microalgae: the leading sector in world aquaculture

“Green water” microalgae: the leading sector in world aquaculture: "

Abstract
Freshwater fish culture is generally considered the largest sector in world aquaculture. Several of the leading species consume
“green water” plankton. This plankton—mostly microalgae (phytoplankton) and also bacteria, protozoa and zooplankton—grows
in man-made fertilized water impoundments. The quantity of “green water” microalgae consumed by fish and shrimp is estimated
here at a quarter billion ton fresh weight a year, about three and a half times as much as the entire recognized aquaculture.
This estimate is based on the quantities of the microalgae consumed and the efficiencies of their use for growth by the main
species in aquaculture. The cost of producing “green water” microalgae by the aquaculturists—mostly in SE Asia—is low. The
populations in “green water” are biologically managed by the cultured fish themselves. The fish with their different feeding
habits help “manage” the composition of the plankton and the overall water quality as they grow. The aquaculturists further
manage “green water” through simple means, including water exchange and fertilization. Cost is remunerated partially by the
income from sales of the fish and partially by bio mitigation services that “green water” polyculture ponds provide the aquaculturists
in treating farm and household waste. A comprehension of the scale and importance of the microalgae sector to world aquaculture
should lead to more research to improve understanding of algal population dynamics, growth factors, and efficiency of food
chains. The consequent improved control of the plankton’s interaction with fish and shrimp production in “green water” will
undoubtedly contribute much to the expansion in production of seafood.


  • Content Type Journal Article
  • DOI 10.1007/s10811-010-9531-9
  • Authors

    • Amir Neori, National Centre for Mariculture Israel Oceanographic and Limnological Research P.O. Box 1212 Eilat 88112 Israel


"
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Simultaneous saccharification of cassava starch and fermentation of algae for biodiesel production

Simultaneous saccharification of cassava starch and fermentation of algae for biodiesel production: "

Abstract
A simpler approach to produce biodiesel from cassava starch was established, which successfully integrates the simultaneous
saccharification and heterotrophic algal fermentation in an identical system. Batch experiments were investigated to verify
the feasibility of raw starchy substrates fermentation for microalgal oil. The highest cell density (49.34 g L−1) and oil content (54.60%) were obtained in 5-L fed-batch cultivation via simultaneous saccharification and fermentation (SSF).
It is demonstrated that the previous multistep hydrolysis and fermentation for feedstock oil could be replaced by SSF with
higher energy efficiency and lower facility costs.


  • Content Type Journal Article
  • DOI 10.1007/s10811-010-9549-z
  • Authors

    • Yue Lu, Tsinghua University School of Life Sciences Beijing 100084 People’s Republic of China
    • Yi Ding, Tsinghua University School of Life Sciences Beijing 100084 People’s Republic of China
    • Qingyu Wu, Tsinghua University School of Life Sciences Beijing 100084 People’s Republic of China


"
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Spirulina (Arthrospira) industry in Inner Mongolia of China: current status and prospects

Spirulina (Arthrospira) industry in Inner Mongolia of China: current status and prospects: "

Abstract
This paper outlines an investigation on current situation of Spirulina (Arthrospira) industry in Inner Mongolia, an internal region of China with temperate continental climate. More than 20 Spirulina plants have been established in Inner Mongolia since 2001, most of which are located at Wulan Town in the Ordos Plateau.
By the end of 2009, the total annual production of Spirulina in the Ordos Plateau surpassed 700 t (dw), which account for ca. 80% of the total productivity of Inner Mongolia, and ca. 20% of China. Besides abundant solar radiation and enough freshwater favorable for Spirulina production, the three technical strategies contribute to the prosperity and success of Spirulina industry in the region: (1) reducing the cost or investment by overall advantages of rich local natural resources with low
cost for Spirulina production, such as alkaline lakes, coal, electricity, and sandy land; (2) controlling the culture temperature and to avoid
contamination by building plastic greenhouses on raceway ponds, (3) reducing investment by simplifying the construction of
the ponds and the greenhouses. As the result, the growth period of Spirulina has been prolonged from about 120 to about 165 days, the cost of Spirulina has decreased by 25–30%, and the quality of products has been enhanced substantially. Inner Mongolia is expected to become
the largest base for Spirulina production not only in China, but also in the world in the near future.


  • Content Type Journal Article
  • DOI 10.1007/s10811-010-9552-4
  • Authors

    • Yun-Ming Lu, Shenzhen Ludebao Health Food Co., Ltd. Shenzhen 518040 China
    • Wen-Zhou Xiang, Chinese Academy of Sciences South China Sea Institute of Oceanology Guangzhou 510301 China
    • Yong-Huang Wen, Shenzhen Ludebao Health Food Co., Ltd. Shenzhen 518040 China


"
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Nutritional value of selected macroalgae

Nutritional value of selected macroalgae: "

Abstract
Macroalgae are traditionally used in human and animal nutrition. Their protein and fiber content have been widely studied
and differ according to the species, their geographic origin and their seasonal conditions. In addition to their value for
human nutrition, seaweeds have multiple therapeutically applications (e.g., weight control, hypocholesterolemic, antioxidant
and antitumor activities, others) and, in general, contribute and promote human health. In the archipelago of the Azores,
the consumption of seaweeds is widespread and accepted as a common practice in some islands. This work is aimed at providing
information on the protein and fiber content of the locally consumed species, to promote this regional food product that can
be potentially profitable from the biotechnology and commercial perspective, and also benefit public health, particularly,
taking into account the low level of marine pollution in the Azores archipelago. Protein and fiber content of eight seaweeds
(Porphyra sp., Osmundea pinnatifida, Pterocladiella capillacea, Sphaerococcus coronopifolius, and Gelidium microdon, Rhodophyta; Cystoseira abies-marina and Fucus spiralis, Phaeophyta; Ulva compressa, Chlorophyta) were determined using the Kjeldahl method and the Weende method, respectively. The protein content ranged from
6.81 to 26.62 of dry weight for C. abies-marina and U. compressa, respectively. Fiber content was generally higher as compared with that in seaweeds from other origins and ranged from 33.82
to 63.88 for O. pinnatifida and F. spiralis, respectively.


  • Content Type Journal Article
  • DOI 10.1007/s10811-010-9556-0
  • Authors

    • Rita Ferreira Patarra, Universidade dos Açores Grupo Biologia Marinha, Departamento Biologia Apartado 1422 9501-801 Ponta Delgada S. Miguel, Açores Portugal
    • Lisete Paiva, Universidade dos Açores Departamento Ciências Tecnológicas e Desenvolvimento (DCTD) 9501-855 Ponta Delgada S. Miguel, Açores Portugal
    • Ana Isabel Neto, Universidade dos Açores Grupo Biologia Marinha, Departamento Biologia Apartado 1422 9501-801 Ponta Delgada S. Miguel, Açores Portugal
    • Elisabete Lima, Universidade dos Açores Centro de Investigação de Recursos Naturais dos Açores (CIRN), Departamento Biologia 9501-801 Ponta Delgada S. Miguel, Açores Portugal
    • José Baptista, Universidade dos Açores Centro de Investigação de Recursos Naturais dos Açores (CIRN), Departamento Biologia 9501-801 Ponta Delgada S. Miguel, Açores Portugal


"
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Cultivation of Chlorella emersonii with flue gas derived from a cement plant

Cultivation of Chlorella emersonii with flue gas derived from a cement plant: "

Abstract
The present study reviews the options of cultivating the green alga, Chlorella emersonii, under photoautotrophic conditions with flue gas derived from a cement plant. It was conducted in the Lafarge Perlmooser
plant in Retznei, Austria, where stone coal and various surrogate fuels such as used tyres, plastics and meat-and-bone meal
are incinerated for heating limestone. During 30 days of cultivation, flue gas had no visible adverse effects compared to
the controls grown with pure CO2. The semi-continuous cultivation with media recycling was performed in 5.5-L pH-stat photobioreactors. The essay using CO2 from flue gas yielded a total of 2.00 g L−1 microalgal dry mass and a CO2 fixation of 3.25 g L−1. In the control, a total of 2.06 g L−1 dry mass was produced and 3.38 g L−1 CO2 was fixed. Mean growth rates were between 0.10 day−1 (control) and 0.13 day−1 (flue gas). No accumulation of flue gas residues was detected in the culture medium. At the end of the experiment, however,
the concentration of lead was three times higher in algal biomass compared to the control, indicating that cultures aerated
with this type of flue gas should not be used as food supplements or animal feed.


  • Content Type Journal Article
  • DOI 10.1007/s10811-010-9551-5
  • Authors

    • Clemens G. Borkenstein, Research and Development BioTech AG BDI–BioDiesel International Parkring 18 8074 Grambach Austria
    • Josef Knoblechner, Research and Development BioTech AG BDI–BioDiesel International Parkring 18 8074 Grambach Austria
    • Heike Frühwirth, Research and Development BioTech AG BDI–BioDiesel International Parkring 18 8074 Grambach Austria
    • Michael Schagerl, University of Vienna Department Limnology Althanstrasse 14 1090 Vienna Austria


"
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Seaweed extract stimuli in plant science and agriculture

Seaweed extract stimuli in plant science and agriculture: "

Abstract
Both micro- and macroalgae have long been used to augment plant productivity and food production in various regions of the
world through their beneficial effects when applied to soils. Interactions of algae with the soil community undoubtedly are
complex and benefits are dependent on the crop and the local environmental conditions. This has resulted in much speculation
as to mechanisms involved as well as the validity of the results reported. It is now 60 years since the first commercial seaweed
extract was manufactured for agricultural use. These aqueous extracts allowed for the first time the direct application of
soluble seaweed constituents to specific plant organs such as leaves and roots. The earlier concept that benefits of seaweeds
and their extracts were due mainly to their manurial value or to their micronutrient suites is no longer tenable. Seaweeds
likewise have been used for millennia as fodder supplements to improve animal nutrition and productivity. Recent research
is focusing on their mode of action, specific health benefits, and the mechanisms of action in animals. Improved analytical
techniques and instrumentation coupled with the use of molecular genetic tools are establishing that seaweed extracts can
modify plant and animal responses at a fundamental level. It therefore seems appropriate to review key developments over the
years and to remark on novel findings. A new and exciting vista has opened for seaweed extracts in both plant and animal applications.


  • Content Type Journal Article
  • DOI 10.1007/s10811-010-9560-4
  • Authors

    • James S. Craigie, Acadian Seaplants Limited 30 Brown Avenue Dartmouth Nova Scotia B3B 1X8 Canada


"
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Seaweed extract stimuli in plant science and agriculture

Seaweed extract stimuli in plant science and agriculture: "

Abstract
Both micro- and macroalgae have long been used to augment plant productivity and food production in various regions of the
world through their beneficial effects when applied to soils. Interactions of algae with the soil community undoubtedly are
complex and benefits are dependent on the crop and the local environmental conditions. This has resulted in much speculation
as to mechanisms involved as well as the validity of the results reported. It is now 60 years since the first commercial seaweed
extract was manufactured for agricultural use. These aqueous extracts allowed for the first time the direct application of
soluble seaweed constituents to specific plant organs such as leaves and roots. The earlier concept that benefits of seaweeds
and their extracts were due mainly to their manurial value or to their micronutrient suites is no longer tenable. Seaweeds
likewise have been used for millennia as fodder supplements to improve animal nutrition and productivity. Recent research
is focusing on their mode of action, specific health benefits, and the mechanisms of action in animals. Improved analytical
techniques and instrumentation coupled with the use of molecular genetic tools are establishing that seaweed extracts can
modify plant and animal responses at a fundamental level. It therefore seems appropriate to review key developments over the
years and to remark on novel findings. A new and exciting vista has opened for seaweed extracts in both plant and animal applications.


  • Content Type Journal Article
  • DOI 10.1007/s10811-010-9560-4
  • Authors

    • James S. Craigie, Acadian Seaplants Limited 30 Brown Avenue Dartmouth Nova Scotia B3B 1X8 Canada


"
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Effect of nitrite on growth and microcystins production of Microcystis aeruginosa PCC7806

Effect of nitrite on growth and microcystins production of Microcystis aeruginosa PCC7806: "

Abstract
As a common pollutant, nitrite concentrations can approach 15 mg NO2−-N L−1 in some aquatic systems. Microcystis aeruginosa blooms are common and widespread in eutrophic freshwater bodies. In this study, M. aeruginosa was exposed to nitrite concentrations ranging from 0 to 15 mg NO2−-N L−1, and the responses of M. aeruginosa were investigated. The specific growth rates, maximum cell densities, light-saturated photosynthetic rates (Pm
chla
), dark respiration rates (Rd
chla
), and apparent photosynthetic efficiencies (αchla
) showed a significant decline with nitrite concentrations increasing. Electrical conductivity and malondialdehyde contents
investigation revealed cell membrane damage and apparent leakage of intracellular contents under high nitrite level conditions
due to oxidative stress enhancement. Intracellular microcystin (MC)-LR content reached the highest value at 10 mg NO2−-N L−1; however, extracellular MC-LR contents showed a continuous increase until 15 mg NO2−-N L−1 owing to the increasing leakage of intracellular contents. These results elucidated that the high-level nitrite inhibited
M. aeruginosa growth by rising oxidative stress, damaging cell membrane, and reducing photosynthesis. However, the moderate increase in
nitrite concentrations promoted toxin production and release of toxin.


  • Content Type Journal Article
  • DOI 10.1007/s10811-010-9558-y
  • Authors

    • Weimin Chen, Henan University College of Environment and Planning Kaifeng 475004 People’s Republic of China
    • Hao Liu, Tianjin University of Technology Engineering Training Center Tianjin 300384 People’s Republic of China
    • Qingmin Zhang, Nankai University College of Environmental Science and Engineering Tianjin 300071 People’s Republic of China
    • Shugui Dai, Nankai University College of Environmental Science and Engineering Tianjin 300071 People’s Republic of China


"
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Isolation and characterization of a new phycoerythrin from the cyanobacterium Synechococcus sp. ECS-18

Isolation and characterization of a new phycoerythrin from the cyanobacterium Synechococcus sp. ECS-18: "

Abstract
A new phycoerythrin, SCH-phycoerythrin, was purified from Synechococcus sp. ECS-18 by DEAE-Sephacel anion exchange chromatography and Sephacryl S-300 gel filtration. The protein pigment had an
absorbance maximum at 542 nm and a fluorescence maximum at 565 nm. The native molecular mass was approximately 219 kDa as
determined by gel filtration, and sodium dodecyl sulfate polyacrylamide gel electrophoresis demonstrated the presence of two
subunits, with molecular mass of 19 and 17.9 kDa. These observations are consistent with the (αβ)6 subunit composition that is characteristic of phycoerythrins. The α- and β-subunits showed immunological identity by Ouchterlony
double immunodiffusion with an anti-phycoerythrin antiserum. The DNA sequence of the SCH-phycoerythrin gene was determined
by PCR amplification using primers based on the conserved N-terminal amino acid sequence of the α- and β-subunits of phycoerythrins.


  • Content Type Journal Article
  • DOI 10.1007/s10811-010-9554-2
  • Authors

    • Jum-Ji Kim, SoonChunHyang University Department of Medical Biotechnology Asan 336-600 Chungnam Republic of Korea
    • Yu-Mi Jeon, SoonChunHyang University Department of Medical Biotechnology Asan 336-600 Chungnam Republic of Korea
    • Jae-Hoon Noh, Korea Ocean Research & Development Institute Ansan P.O. Box 29 425-600 Republic of Korea
    • Mi-Young Lee, SoonChunHyang University Department of Medical Biotechnology Asan 336-600 Chungnam Republic of Korea


"
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