Digital library

  • Kappaphycus (Rhodophyta) Cultivation: Problems and the Impacts of Acadian Marine Plant Extract Powder

    Kappaphycus is one of the most significant, economically valuable red seaweeds, cultivated in tropical and sub-tropical waters. This alga demands a relatively high market value globally, due to applications of the kappa carrageenan colloid that is industrially extracted from the biomass. Carrageenan is widely used in food, pharmaceuticals, nutraceuticals and for aquaculture applications.

    The first successful commercial cultivation of Kappaphycus (previously called Eucheuma) was recorded from the southern Philippines. It took more than five years of fi eld trials from 1967 to the early 70s in order to domesticate Kappaphycus for reliable commercial cultivation. The first commercial quantities of “cottonii” produced from extensive cultivation were obtained in 1974 with a total production of 8,000 t. Dramatic increases in production were achieved and the Philippines was the leading producer of Kappaphycus for 33 years until it was overtaken by Indonesia in 2008. It was in 1978, when Kappaphycus farming first saw successful adoption in Indonesia under the initiative of the Copenhagen Pectin Factory. Due to these successes, Kappaphycus farming has also grown commercially in East Africa, Fiji Is., India, Malaysia, Vietnam, Cambodia, Myanmar and southern China, although their volumes are minimal when compared to Indonesia and the Philippines. On the other hand, Latin American (Argentina, Colombia, Brazil, Equador, Venezuela, Mexico, and Peru) and the Caribbean countries (St. Lucia, Jamaica, and Panama) are even more recent entrants to Kappaphycus cultivation. Most information comes from published pilot-plot, demonstration farms and scientifi c studies, as such, only relatively small commercial quantities are produced presently.

    Author(s): Anicia Q. Hurtado, Renata Perpetuo Reis, Rafael R. Loureiro, Alan T. Critchley

  • Kale of the Sea

    The story of seaweed will take us from a medicine hut in southern Chile to a high-tech seaweed nursery in Stamford, Connecticut, and from biofuels to beer, as we discover the surprising history and bright future of marine vegetables. Along the way, we uncover the role kelp can play in supporting U.S. fishermen, cleaning up coastal waters, and even helping make salmon farms more sustainable.

    Author(s): Cynthia Graber, Nicola Twilley

  • Ka Pili Kai: Limu gifts from the sea

    The legendary Dr. Isabella (Izzie) Kauakea Aiona Abbott, fondly (and aptly) nicknamed "The First Lady of Limu", would have celebrated her 100th birthday this year. In tribute to her, and to celebrate the importance of limu (seaweed) to Hawai'i dating back more than a century, we are dedicating this issue of Ka Pili Kai to Izzie and her legacy. Not only was she a world-renowned scientist, author, professor, mentor, and inspiration to all who knew her, but she also embodied the true spirit of one who dedicated her life to ensuring that the next generation of students of all different backgrounds and cultures had invaluable opportunities to learn and thrive. In the pages of this issue you will read firsthand accounts from just a handful of people, among many, whose lives she shaped, and who are now in a position to carry on her legacy. 

    In another very special tribute to Izzie this year, a brand-new species of red algae, Martensia abbottiae, first found on the deep coral reefs off the coast of Moloka'i, Hawai'i, was named after her. 

    I invite you to browse this issue to read more about Izzie through engaging stories and images, and also learn how limu has helped shape the history of Hawai'i and its people. 

     

    Cindy Knapman

    Hawai'i Sea Grant Communications Leader 

    Author(s): Darren T. Lerner, Heather Dudock, Cindy Knapman, Rachel Lentz, Darren T. Lerner, Maya Walton , Josh McDaniel, Lurline Wailana McGregor, Paula Moehlenkamp, Celia Smith , Miwa Tamanaha, Bill Thomas, Kawika Winter , Andre P. Seale

  • Journal of Fisheries and Aquatic Science

    Background and Objective: Eucheumatoid cultivation is increasing and a variety of methods exist that can increase production. However, new cultivation approaches are rarely reported. The objective of study was to examine a new method of seaweed cultivation: The floating cage.

    Materials and Methods: The growth rate of Eucheuma denticulatum and Kappahycus alvarezii was assessed in floating cages from March-November, 2015 and compared with that in the traditional longline approach. Propagule wet weight was measured daily to document growth rates. Correlation coefficients between growth rate and environmental factors were calculated using simple linear models (Pearsonʼs) and statistically analyzed by SPSS Version 24.

    Results: Growth rates of both species in floating cages were faster than on longline and thallus morphology was better. For E. denticulatum, the daily specific growth rate (SGR) in floating cages varied from a low of 2.68% to a high of 3.32%, but the respective rates on longline were 1.67 and 2.91%. For K. alvarezii cultivated in floating cages, the highest and lowest rates were 3.1 and 2.1% but, when cultivated on longline, the respective rates were 2.9 and 1.71%.

    Conclusion: Therefore, it was concluded that cultivation of E. denticulatum and K. alvarezii using floating cages resulted in higher growth rates compared to cultivation on longline. The difference in results comes from reduced herbivore attack when the plants are in the protective cages.

    Author(s): Ma'ruf Kasim , Ahmad Mustafa, Muzuni Jalil, Wardha Jalil

  • Isolation and culture of protoplasts from agar yielding seaweed Gracilaria edulis (Gmelin) Silva

    Viable protoplasts were isolated from cultured thailus of agar yeilding red seaweed Gracilaria edulis using an enzyme mixture of 3% ONOZUKA R-10 cellulase 3% R-10 macerozyme, 1 % agarase and 1% pectinase in a seaweed protoplast washing medium (SPW) containing seawater and 1 M mannitol. After repeated washing wiih sterile medium, the protoplasts were maintained in light and attempts were made on electrofusion of protoplasts.

    Author(s): Kaladharan, P, Gopinathan, C P, Bindhu, K B, Smitha, K S, Gireesh, R

  • Isolation and characterization of alginate-degrading bacteria for disposal of seaweed wastes

    Aims: Isolation of novel alginate degrading bacteria for the disposal of seaweed waste in composting process.

    Methods and results: Decomposition of alginate polymers was checked by the 3,5-dinitrosalicylic acid (DNS) method for reducing sugar, and absorbance at 235 nm for unsaturated sugar. A bacterium A7 was isolated from wakame compost and confirmed to belong to the genus Gracilibacillus by partial 16S rDNA analysis. The optimum condition for the growth of A7 in a medium containing 5 g l(-1) of sodium alginate is as follows: pH, 8.5-9.5; NaCl, 0.5 mol l(-1); temperature, 30 degrees C and polypeptone as nutrient content, 2-5 g l(-1). In a laboratory-scale composting experiment, the alginate content in wakame compost decreased to 14.3% after 72 h of composting from an initial value of 36%, indicating the effectiveness of alginate decomposition of A7 in wakame composting.

    Conclusions: The bacterium A7 was found to be alginate lyase-producing in genus Gracilibacillus and effective in degrading alginate to oligosaccharides in wakame during composting process.

    Significance and impact of the study: Development of new methods for the disposal of marine wastes and production of functional products.

     
    Author(s): J.-C. Tang, H. Taniguchi, H. Chu, Q. Zhou, S. Nagata

  • Is there a need for seaweed in human nutrition?

    In the Far East and Pacific Islands, there has been a long tradition of consuming seaweed as sea vegetables, while in Western countries the main use of seaweed has been as source of phycocolloids (alginate, carrageenan and agar) used as thickening and gelling agents in various industrial applications, including food processing. Seaweed is also a source of compounds with protective health effects. The beneficial effects of seaweed on human health appear to derive from the presence of three categories of constituents (fibre, proteins and minerals) as well as metabolites with antioxidant properties, including carotenoids, polyphenols, vitamins and polyunsaturated fatty acids.

    Author(s): H. Marfaing, Y. Lerat

  • Is Red Seaweed the Next Big Thing in Plant-Based Protein?
    Earlier this year, GFI announced the winners of our inaugural Competitive Research Grant Program. Thanks to the generosity of two visionary donors, we were able to allocate three million dollars in research funding to fourteen scientists from all corners of the globe—from Estonia to China to Israel—for critical, open-access research in plant-based and cell-based protein.
     
    Over the next few months, we will dive into each project with the scientists leading the charge. Today we start off in the U.S., where technologist and ocean entrepreneur Beth Zotter is researching a unique source of plant-based protein: red seaweed. Red seaweed has a high protein content and a remarkable umami flavor. Its “red-meat like attributes” are perfectly fit for alternative protein products.
     
    Zotter and her team at Trophic LLC are creating a method of protein extraction specifically for seaweed. They aim to test different protein concentrates to find the best fit based on cost and quality, as well as to characterize the taste and texture of different species. Zotter is transforming the possibilities for seaweed. She spoke to us about how the plant “can feed the world,” the importance of nori, and even a species that tastes like bacon.
    Author(s): Tara DiMaio

  • Is inland aquaculture the panacea for Sierra Leone’s decline in marine fish stocks?

    The literature on fisheries for developing countries often cites inland aquaculture as a promising source of wealth creation for a nation in terms of revenue generation from export products. However, in this paper we argue that inland aquaculture has a greater prospect of success if it focuses on social welfare – i.e. alleviating food insecurity and poverty in coastal fishing communities, particularly those that are experiencing increased and unsustainable fishing pressure on marine fish. Nevertheless, promoting inland aquaculture in coastal areas faces many chal- lenges, including financial, legal, political, environmental, logistical, educational, and attitudinal obstacles. Our study investigates these challenges in two coastal communities in Sierra Leone – Tombo and Goderich – where declining levels of marine fish catches are intensifying efforts to provide alternative or supplementary forms of employment for artisanal fishers, but where knowledge and experience of, and enthusiasm and funding for, inland aquaculture are limited. The research is based on the perceptions of 51 key informant interviewees and 199 survey questionnaire respondents. The main findings of the fieldwork are as follows. (1) Few local fishers were familiar with inland aquaculture and its potential benefits. (2) There were land tenure problems (for example, women were excluded from ownership of land). (3) There was little funding to buy/rent land and equipment. (4) Despite declining fish stocks, respondents were reluctant to take up full-time fish farming because of the easier option of fishing. Our findings suggest that greater uptake of inland aquaculture is more likely if presented to local fishers as a supplementary livelihood activity rather than an alternative occupation to marine capture fishing. Our study reinforces the importance of understanding local fishers’ cultures, values, and pref- erences before introducing a new livelihood activity.

    Author(s): Nwamaka Okeke-Ogbuafor, Selina Stead, Tim Gray

  • Iodine monoxide at a clean marine coastal site: observations of high frequency variations and inhomogeneous distributions

    The first in situ point observations of iodine monoxide (IO) at a clean marine site were made using a laser-induced fluorescence instrument deployed at Mace Head, Ireland in August 2007. IO mixing ratios of up to 49.8 pptv (equivalent to pmol mol−1; 1 s average) were ob- served at day-time low tide, well in excess of previous ob- served spatially-averaged maxima. A strong anti-correlation of IO mixing ratios with tide height was evident and the high time resolution of the observations showed IO peaked in the hour after low tide. The temporal delay in peak IO compared to low tide has not been observed previously but coincides with the time of peak aerosol number previously observed at Mace Head.

    A long path-differential optical absorption spectroscopy instrument (with a 2 × 6.8 km folded path across Roundstone Bay) was also based at the site for 3 days during the point measurement observation period. Both instruments show similar temporal trends but the point measurements of IO are a factor of ∼6–10 times greater than the spatially averaged IO mixing ratios, providing direct empirical evidence of the presence of inhomogeneities in the IO mixing ratio near the intertidal region.

    Author(s): R. Commane, K. Seitz, C. S. E. Bale, W. J. Bloss, J. Buxmann, T. Ingham, U. Platt, D. Pohler, D. E. Heard

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