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  • Seaweed as Bioplastic Research - Ch. 1 and 2

    Plastics are carbon-based polymers and we make them mostly from petroleum. With the discovery of plastics, life became much more convenient because it is used to make a wide array of useful materials. But these plastics are so durable that it will take many centuries for these plastics to completely degrade while other plastics will last forever. Discarded plastics are also a big cause of pollution and because of that, plastics make our environment a much less attractive place (Atienza, 2009).

    Getting rid of plastics is extremely difficult. Burning these plastics gives off harmful chemicals such as dioxins that could contribute to Global Warming. Recycling these plastics is also difficult because there are many different kinds of plastics and each has to be recycled by a different process. Though these plastics are considered to be one of the greatest innovations ever, they are also imposing a great havoc to the environment, the wildlife and the general public (Woodford, 2008). For this reason, this study aims to develop a biomass-based plastic from the natural polysaccharides of seaweeds.

    Biomass-based plastics or bioplastics are a form of plastics derived from renewable biomass resources like vegetable oil or corn starch rather than the conventional plastics which are made from petroleum. Their advantage are innumerable and one is their capability to biodegrade naturally within a short period of time only (Sweeney, 2008). 

    Seaweeds are best known for the natural polysaccharides that can be extracted from them which are widely used particularly in the fields of food technology, biotechnology, microbiology and even medicine but not yet in the plastic industry. Some of these polysaccharides are Floridean starch, agar and alginate (Montano, 2010) Since they are renewable biomass resources and are polymers made from sugars which contain carbon, they could be used to create a bioplastic. 

    In this study, the natural polysaccharides from selected Philippine marine seaweeds will be utilized to develop a biodegradable and high-quality bioplastic. 

    Author(s):

  • Seaweed as innovative feedstock for energy and feed - Evaluating the impacts through a Life Cycle Assessment

    Offshore cultivation of seaweed provides an innovative feedstock for biobased products supporting blue growth in northern Europe. This paper analyzes two alternative exploitation pathways: energy and protein production. The first pathway is based on anaerobic digestion of seaweed which is converted into biogas, for production of electricity and heat, and digestate, used as fertilizer; the second pathway uses seaweed hydrolysate as a substrate for cultivation of heterotrophic microalgae. As a result the seaweed sugars are consumed while new proteins are produced enhancing the total output. We performed a comparative Life Cycle Assessment of five scenarios identifying the critical features affecting resource efficiency and environmental performance of the systems with the aim of providing decision support for the design of future industrial scale production processes. The results show that all scenarios provide environmental benefits in terms of mitigation of climate change, with biogas production from dried Laminaria digitata being the most favorable scenario, quantified as 18.7*102 kg CO2 eq./ha. This scenario presents also the lowest consumption of total cumulative energy demand, 1.7*104 MJ/ha, and even resulting in a net reduction of the fossil energy fraction, 1.9*104 MJ/ha compared to a situation without seaweed cultivation. All scenarios provide mitigation of marine eutrophication thanks to bioextraction of nitrogen and phosphorus during seaweed growth. The material consumption for seeded lines has 2e20 times higher impact on human toxicity (cancer) than the reduction achieved by energy and protein substitution. However, minor changes in cultivation design, i.e. use of stones instead of iron as ballast to weight the seeded lines, dramatically reduces human toxicity (cancer). Externalities from the use of digestate as fertilizer affect human toxicity (non-cancer) due to transfer of arsenic from aquatic environment to agricultural soil. However concentration of heavy metals in digestate does not exceed the limit established by Danish regulation. The assessment identifies seaweed productivity as the key parameter to further improve the performance of the production systems which are a promising service provider of environmental restoration and climate change mitigatio

    Author(s): Michele Seghetta, Daina Romeo, Martina D'Este, Merlin Alvarado-Morales, Irini Angelidaki, Simone Bastianoni, Marianne Thomsen

  • Seaweed Bioactive Compounds against Pathogens and Microalgae: Potential Uses on Pharmacology and Harmful Algae Bloom Control

    Cyanobacteria are found globally due to their adaptation to various environments. The occurrence of cyanobacterial blooms is not a new phenomenon. The bloom-forming and toxin-producing species have been a persistent nuisance all over the world over the last decades. Evidence suggests that this trend might be attributed to a complex interplay of direct and indirect anthropogenic influences. To control cyanobacterial blooms, various strategies, including physical, chemical, and biological methods have been proposed. Nevertheless, the use of those strategies is usually not effective. The isolation of natural compounds from many aquatic and terrestrial plants and seaweeds has become an alternative approach for controlling harmful algae in aquatic systems. Seaweeds have received attention from scientists because of their bioactive compounds with antibacterial, antifungal, anti-microalgae, and antioxidant properties. The undesirable effects of cyanobacteria proliferations and potential control methods are here reviewed, focusing on the use of potent bioactive compounds, isolated from seaweeds, against microalgae and cyanobacteria growth.

    Author(s): Soukaina El Amrani Zerrifi, Fatima El Khalloufi, Brahim Oudra, Vitor Vasconcelos

  • Seaweed Bioethanol Production in Japan - The Ocean Sunrise Project

    Seaweed Bioethanol Production in Japan, titled the “Ocean Sunrise Project”, aims to produce seaweed bioethanol by farming and harvesting Sargassum horneri, utilizing 4.47 million km² (sixth largest in the world) of unused areas of the exclusive economic zone (EEZ) and maritime belts of Japan. Through seaweed bioethanol production, the Project aims to combat global warming by contributing an alternative energy to fossil fuel. This paper outlines the results of the project’s feasibility research conducted by Tokyo Fisheries Promotion Foundation.

    Author(s): Toshitsugu Sakou, Masaya Atsumi, Ken Asaoka, Masahito Aizawa

  • Seaweed biofilters as regulators of water quality in integrated fish-seaweed culture units

    The water-quality characteristics of a new system for the integrated culture of fish ( Sparus aurata L.) and seaweed ( Ulva lactuca L.) were examined. Seawater was recirculated between intensive fishponds and seaweed ponds. The seaweed removed most of the ammonia excreted by the fish and oxygenated the water. A model consisting of several tanks and a pilot consisting of two 100-m 3 , 100-m 2 ponds were studied. In both, the metabolically dependent water-quality parameters (dissolved oxygen, NH 4 + -N, oxidized-N, pH and phosphate) remained stable and within safe limits for the fish during over 2 years of operation. The design allowed significant increases in overall water residence time (4.9 days), compared with conventional intensive ponds, and produced a high yield of seaweed in addition to the fish. The design provides a practical solution to major management and environmental problems of land-based mariculture

    Author(s): Hillel Gordin, Dror Angel, Michal Ucko, Daniel Zuber, Orit Dvir, Patrick J. Davison, Ruth Rabinovitch, Dan Popper, Claude E. Boyd, Steve P. Ellner, Michael D. Krom, Amir Neori

  • Seaweed biofuels: a green alternative that might just save the planet

    "It's best to get it out of the water now or it'll start getting grazed by the little beasties," says Lars Brunner as he hauls 50kg of glistening, translucent kelp from the dark waters of the Sound of Kerrera into the boat. The long summer days mean the seaweed is rapidly storing up sugars, which snails and barnacles find delicious.

    Author(s): Damian Carrington

  • Seaweed Biology - Novel Insights into Ecophysiology, Ecology and Utilization

    Two thirds of the world are covered by oceans, whose upper layer is inhabited by photoautotrophic organisms, known as algae. Within coastal ecosystems, marine seaweeds have been identified as a group of organisms of vital importance for ecosystem function. On rocky coasts, they form vast underwater forests of consid- erable size with a structure similar to terrestrial forests and provide diverse habitats and breeding areas for an uncountable number of organisms including fishes and crustaceans. They are an important food source not only for numerous herbivores, such as sea urchins, gastropods, and chitons, but also for detritivores such as filter feeders and zooplankton, which are feeding on degraded seaweed biomass and on energy-rich spores released in vast quantities from seaweeds. On beaches in some localities large masses of seaweeds are stranded and support meiofauna species.

    Although marine seaweeds and seagrasses, altogether known as macrophytes, cover only a minute area of the world’s oceans, their production amounts to 5–10% of the total oceanic production. Carbon assimilation of kelps, large brown algae of the order Laminariales, is with 1.8 kg carbon m2 year1 similarly high as that of dense terrestrial forests and even exceeds the primary production of marine phyto- plankton up to ten times.

    Seaweeds are not only of high ecological, but also of great economic impor- tance. Dried thalli are directly used as human and animal food and also as fertilizer. Extracted seaweed substances are used as stabilizers and stiffeners in food industry, cosmetics, pharmaceutical industry, and biotechnology. In future, aquaculture of seaweeds will certainly strongly intensify, especially in integrated multi-trophic aquaculture systems making use of the waste products or biomass generated by other organisms in the system. Industrial use of seaweeds will also strongly increase as basis for CO2-neutral production of ethanol and methanol as biofuels.

    Author(s): Christian Wiencke, Kai Bischof

  • Seaweed biorefinery concept for sustainable use of marine resources Karina Balina*, Francesco Romagnoli, Dagnija Blumberga Institute of Energy Systems and Environment, Riga Technical University, Azenes iela 12/1, Riga, LV–1048, Latvia Abstract Seaweed

    Seaweed, also called marine macroalgae, have a potential to be a valuable feedstock for biorefinery. Depending from seaweed type and species it is possible to extract different fatty acids, oils, natural pigments, antioxidants, high value biological components and other substances which can be potentially used in an industrial production system. The seaweed biorefinery framework presents a conceptual model for high value added product production along with production of biofuels either fluid or gaseous. This in turn reduces the cost of fuel production with maximum utilization of the biomass. The role of seaweed biorefinery concept is analysed in this paper under the perspective of bioeconomy principles and through a SWOT analysis was made to indicate the role biorefinery concept can play to support the development of sustainable bioeconomy. 

    Author(s): Karina Balina, Francesco Romagnoli, Dagnija Blumberga

  • Seaweed biorefinery: production of fuels and chemicals from native North Sea seaweed species
    • The ‘Seaweed Biorefinery’ project: general description
    • Composition of seaweed species for biorefinery
    • Biorefinery of green seaweeds (local Ulva lactuca)
    • Biorefinery of brown seaweed species:
    • Saccharina latissima as model feedstock
          • mannitol and alginate extraction
          • fermentation of mannitol/glucose to acetone, butanol and ethanol
    Author(s): Ana López-Contreras, Paulien Harmsen, Rolf Blaauw, Rob Bakker, Jaap van Hal, Hans Reith, Willem Brandenburg, Jacco van Haveren

  • Seaweed Biorefinery: Towards Third Generation Biobased Commodoties

    Drivers for seaweed cultivation in the Dutch North Sea

    • No existing seaweed industry

    • Development of biobased economy (agricultural crops, lignocellulose residues, microalgae,..)

    • Interest in seaweeds:

    - No competition with food or other land use issues

    - High biomass productivity

    - Versatile feedstock: numerous options for chemicals and fuels via biorefinery

    - Biochemical composition: complementary (for chemicals/fuel production) to micro-algae

    • Development offshore wind turbine parks

    Author(s): Ana M. López Contreras, Hans Reith, Jip Lenstra, Jaap W. van Hal

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