Digital library

  • A Guide to the Seaweed Industry

    Seaweed is a very versatile product widely used for food in direct human consumption. It is also ingredient for the global food and cosmetics industries and is used as fertilizer and as an animal feed additive. Total annual value of production is estimated at almost US$ 6 billion. Total annual use by the global seaweed industry is about 8 million tonnes of wet seaweed.

    Seaweed can be collected from the wild but is now increasingly cultivated. It falls into three broad groups based on pigmentation; brown, red and green seaweed. Use of seaweed as food has strong roots in Asian countries such as China, Japan and the Republic of Korea, but demand for seaweed as food has now also spread to North America, South America, and Europe. China is by far the largest seaweed producer followed by the Republic of Korea and Japan but seaweeds are today produced in all continents.

    Red and brown seaweeds are also used to produce hydrocolloids; alginate, agar and carrageenan, which are used as thickening and gelling agents. Today, approximately 1 million tonnes of wet seaweed are harvested and extracted to produce about 55 000 tonnes of hydrocolloids, valued at almost US$600 million.

    Author(s): Dennis J. McHugh

  • A new Norwegian bioeconomy based on cultivation and processing of seaweeds: Opportunities and R&D needs

    Cultivation of macroalgae at the lowest trophic level, using only sunlight and nutrients from the sea while taking up CO2, will have a neutral carbon footprint and the biomass will contribute significantly to meet the demand for food, feed, materials, chemicals, fuels and pharmaceuticals in near future. Through a new bioeconomy based on cultivated macroalgae Norway will establish a future feedstock bypassing the competition with landbased agricultural resources and at the same time contribute to the replacement of fossil resources. This blue bioeconomy will strenghten Norway's role as the leading seafood nation as well as a leading supplier of marine, sustainable biomass. In order to boost a new bioeconomy based on cultivated macroalgae, three priority areas must be focused:

    • Biomass production technology

    • Biorefinery prosesses

    • Marked and product development

    Author(s): Jorunn Skjermo, Inga Marie Aasen, Johanne Arff, Ole Jacob Broch, Ana Carvajal, Hartvig Christie, Silje Forbord, Yngvar Olsen, Kjell Inge Reitan, Turid Rustad, Judit Sandquist, Roar Solbakken, Kristine B. Steinhovden, Bernd Wittgens, Robert Wolff , Aleksander Handå

  • A Novel Ocean Color Index to Detect Floating Algae n the Global Oceans

    Various types of floating algae have been reported in open oceans and coastal waters, yet accurate and timely detection of these relatively small surface features using traditional satellite data and algorithms has been difficult or even impossible due to lack of spatial resolution, coverage, revisit frequency, or due to inherent algorithm limitations. Here, a simple ocean color index, namely the Floating Algae Index (FAI), is developed and used to detect floating algae in open ocean environments using the medium-resolution (250- and 500- m) data from operational MODIS (Moderate Resolution Imaging Spectroradiometer) instruments. FAI is defined as the difference between reflectance at 859 nm (vegetation “red edge”) and a linear baseline between the red band (645 nm) and short-wave infrared band (1240 or 1640 nm). Through data comparison and model simulations, FAI has shown advantages over the traditional NDVI (Normalized Difference Vegetation Index) or EVI (Enhanced Vegetation Index) because FAI is less sensitive to changes in environmental and observing conditions (aerosol type and thickness, solar/viewing geometry, and sun glint) and can “see” through thin clouds. The baseline subtraction method provides a simple yet effective means for atmospheric correction, through which floating algae can be easily recognized and delineated in various ocean waters, including the North Atlantic Ocean, Gulf of Mexico, Yellow Sea, and East China Sea. Because similar spectral bands are available on many existing and planned satellite sensors such as Landsat TM/ETM+ and VIIRS (Visible Infrared Imager/Radiometer Suite), the FAI concept is extendable to establish a long-term record of these ecologically important ocean plants

    Author(s): Chuanmin Hu

  • A review of bioactive plant polysaccharides: Biological activities, functionalization, and biomedical applications

    Natural polysaccharides from different sources have long been studied and widely used in different areas, such as food and feed, medicine and pharmaceutics, and in papermaking. In recent decades, there has been an increased interest in the utilization of polysaccharides, particularly bioactive ones, for various novel applications owing to their biocompatibility, biodegradability, non-toxicity, and some specific therapeutic activities. The main goal of this paper was to review the sources, natively biological activities, isolation, characterization, and the structural features of natively bioactive polysaccharides. Moreover, the article has also been forcused on the chemical/chemo-enzymatic functionalizations that may create novel opportunities to maximally exploit the various valuable properties of polysaccharides, particularly from wood species, in previously unperceived applications especially for biomedical applications, such as tissue engineering, wound healing, and drug delivery. This article was to review novel strategies to tailor functional materials with above mentioned application potentials for the polysaccharides from wood species.

    Author(s): Jun Liu, Stefan Willfor, Chunlin Xu

  • A REVIEW OF KAPPAPHYCUS FARMING IN BRAZIL

    The success of commerical cultivation of Kappaphycus seaweed in several countries is directly related to the easy vegetative reproduction of this species, high growth rate, simple cultivation techniques and their uses in different segments of the food, pharmaceutical, cosmetic and agricultural industries.

    Author(s): Miguel Sepulveda

  • A SELECTED BIBLIOGRAPHY ON SEAWEED AQUACULTURE RESEARCH AND DEVELOPMENT IN THE TROPICAL PACIFIC

    Scope

    This Bibliography has attempted to cover materials on seaweeds and seaweed products relevant to the tropical Pacific region, particularly the Pacific island countries, although many references also relate to other countries in the Tropics . In addition, references on Ciguatera-causing algae are also included. The bibliography was compiled using a number of sources for the references, including personal libraries. Several databases were machine searched, and most of the Eucheuma references that are included here are post 1987 as the older literature has been adequately reviewed. References on seagrass are also included. There are also several other recent reviews available on related aspects. The Akatsuka volume announced for publication in 1992 should be consulted as should the Proceedings of the XlVth International Seaweed Symposium and a special issue (No.2) of volume 5 of the Journal of Applied Phycology. The "Grey" literature has been more difficult to trace, and undoubtedly pertinent reports have been missed, hence this is not an exhaustive list.

    Author(s): G. R. South, G. Rao, J. L. McLachlan

  • A short-term response of macroalgae to potential competitor removal in a mid-intertidal habitat in Korea

    Abstract Interspecific interactions among three dominant macroalgae, Pterocladia capillacea (Rhodophyta), Hizikia fusiformis (Heterokontophyta) and Chondracanthus intermedius (Rhodophyta), were experimentally investigated on the rocky mid-intertidal zone of Sungsan, Jeju Island, Korea from March 1998 to June 1999. Each of the potentially competing species was removed in permanent plots (20 x 20 em), and percent covers of non-manipulated species were measured by an image analyzing method using a digital camera. Pterocladia capillacea was the most abundant during all seasons, except for winter. Its abundance was lowered by the removal of the turf-forming alga C. intermedius, indicating that turf had a positive effect on P. capillacea. Conversely, there was a negative effect of P. capillacea on the abundance of C. intermedius. Interactions between C. intermedius and P. capillacea can probably be explained as a consequence of the water-trapping ability of the former and the canopy-forming ability of the latter. There was, however, no apparent effect related to H. fusiformis since the abundance of this alga remained low. This study supports that both negative and positive effects between same pair of species could be common depending on the morphological differences of algae and particular habitat conditions

    Author(s): Hyun Jin Kim, Jeong Ha Kim, Sang Rul Park, Yong Ju Bhang, Hyun Ah Lee, Seungshic Yum, Hyuk Je Lee, Baek Jun Kim

  • A Simple and Effective Method for High Quality Co- Extraction of Genomic DNA and Total RNA from Low Biomass Ectocarpus siliculosus, the Model Brown Alga

    The brown seaweed Ectocarpus siliculosus is an emerging model species distributed worldwide in temperate coastal ecosystems. Over 1500 strains of E. siliculosus are available in culture from a broad range of geographic locations and ecological niches. To elucidate the molecular mechanisms underlying its capacity to cope with different environmental and biotic stressors, genomic and transcriptomic studies are necessary; this requires the co-isolation of genomic DNA and total RNA. In brown algae, extraction of nucleic acids is hindered by high concentrations of secondary metabolites that co-precipitate with nucleic acids. Here, we propose a reliable, rapid and cost-effective procedure for the co-isolation of high-quality nucleic acids using small quantities of biomass (25-, 50- and 100 mg) from strains of E. siliculosus (RHO12; LIA4A; EC524 and REP10-11) isolated from sites with different environmental conditions. The procedure employs a high pH extraction buffer (pH 9.5) which contains 100 mM Tris-HCl and 150 mM NaCl, with the addition of 5 mM DTT and 1% sarkosyl to ensure maximum solubility of nucleic acids, effective inhibition of nuclease activity and removal of interfering contaminants (e.g. polysaccharides, polyphenols). The use of sodium acetate together with isopropanol shortened precipitation time and enhanced the yields of DNA/RNA. A phenol:chlorophorm:isoamyl alcohol step was subsequently used to purify the nucleic acids. The present protocol produces high yields of nucleic acids from only 25 mg of fresh algal biomass (0.195 and 0.284 µg mg(-1) fresh weigh of RNA and DNA, respectively) and the high quality of the extracted nucleic acids was confirmed through spectrophotometric and electrophoretic analyses. The isolated RNA can be used directly in downstream applications such as RT-PCR and the genomic DNA was suitable for PCR, producing reliable restriction enzyme digestion patterns. Co-isolation of DNA/RNA from different strains indicates that this method is likely to have wider applications for intra- and inter-specific studies on other brown algae.

    Author(s): Maria Beatrice Bitonti, Murray T. Brown, Claudio A. Sáez, Maria Greco

  • A systematic review of anti-obesity medicinal plants - an update

    Obesity is the most prevalent health problem affecting all age groups, and leads to many complications in the form of chronic heart disease, diabetes mellitus Type 2 and stroke. A systematic review about safety and efficacy of herbal medicines in the management of obesity in human was carried out by searching bibliographic data bases such as, PubMed, Scopus, Google Scholar, Web of Science, and IranMedex, for studies reported between 30th December 2008 to 23rd April 2012 on human or animals, investigating the beneficial and harmful effects of herbal medicine to treat obesity. Actually we limited our search to such a narrow window of time in order to update our article published before December of 2008. In this update, the search terms were “obesity” and (“herbal medicine” or “plant”, “plant medicinal” or “medicine traditional”) without narrowing or limiting search items. Publications with available abstracts were reviewed only. Total publications found in the initial search were 651. Total number of publications for review study was 33 by excluding publications related to animals study. Studies with Nigella Sativa, Camellia Sinensis, Crocus Sativus L, Seaweed laminaria Digitata, Xantigen, virgin olive oil, Catechin enriched green tea, Monoselect Camellia, Oolong tea, Yacon syrup, Irvingia Gabonensi, Weighlevel, RCM104 compound of Camellia Sinensis, Pistachio, Psyllium fibre, black Chinese tea, sea buckthorn and bilberries show significant decreases in body weight. Only, alginate-based brown seaweed and Laminaria Digitata caused an abdominal bloating and upper respiratory tract infection as the side effect in the trial group. No other significant adverse effects were reported in all 33 trials included in this article. In conclusion, Nigella Sativa, Camellia Synensis, Green Tea, and Black Chinese Tea seem to have satisfactory antiobesity effects. The effect size of these medicinal plants is a critical point that should be considered for interpretation. Although there was no report for side effect in these trials, we believe that safety of these plants still remains to be elucidated by further long-term studies.

    Author(s): Mohammad Abdollah, Zahra Jouyandeh, Shirin Hasani-Ranjbar

  • A Systematic Review on Seaweed Functionality: A Sustainable Bio-Based Material

    Sustainable development is an integrated approach to tackle ongoing global challenges such as resource depletion, environmental degradation, and climate change. However, a paradigm shift from a fossil-based economy to a bio-based economy must accomplish the circularity principles in order to be sustainable as a solution. The exploration of new feedstock possibilities has potential to unlock the bio-based economy’s true potential, wherein a cascading approach would maximize value creation. Seaweed has distinctive chemical properties, a fast growth rate, and other promising benefits beyond its application as food, making it a suitable candidate to substitute fossil-based products. Economic and environmental aspects can make seaweed a lucrative business; however, seasonal variation, cultivation, harvesting, and product development challenges have yet not been considered. Therefore, a clear forward path is needed to consider all aspects, which would lead to the commercialization of financially viable seaweed-based bioproducts. In this article, seaweed’s capability and probable functionality to aid the bio-based economy are systematically discussed. The possible biorefinery approaches, along with its environmental and economic aspects of sustainability, are also dealt with. Ultimately, the developmental process, by-product promotion, financial assistance, and social acceptance approach are summarized, which is essential when considering seaweed-based products’ feasibility. Besides keeping feedstock and innovative technologies at the center of bio-economy transformation, it is imperative to follow sustainable-led management practices to meet sustainable development goals.

    Author(s): Pranav Nakhate, Yvonne van der Meer

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