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  • From February 9 to 12, 2020, we organized a special session at the Aquaculture of America meetings held at the Hawai'i Convention Center in Honolulu on the island of Oahu. The session, entitled “Seaweed aquaculture – from historic trends to current innovation” included over 20 presenters. The session encompassed the breadth of seaweed research that has arisen in the last decade and beyond. It spanned topics from seaweed tank and pond cultivation, off-shore design and deployment, genetics and strain selection, algae education, uses and processing of algae for food, feed and biofuel, and the compounding challenges facing this developing industry. Currently, the global seaweed industry is valued at more than US $11 billion, and is dominated by production in Asian countries including China, Indonesia, Korea, and Japan (FAO, 2020). Almost 97% of this global supply is aquaculture-sourced seaweeds (Costa-Pierce, 2021; Costa-Pierce & Chopin, 2021; Piconi, Veidenheimer, & Bob, 2020).

    Author(s): Yarish, Charles Simona Augyte, Jang K. Kim
  • Macroalgae, or seaweeds, are a rich source of components which may exert beneficial effects on the mammalian gut microbiota through the enhancement of bacterial diversity and abundance. An imbalance of gut bacteria has been linked to the development of disorders such as inflammatory bowel disease, immunodeficiency, hypertension, type-2-diabetes, obesity, and cancer. This review outlines current knowledge from in vitro and in vivo studies concerning the potential therapeutic application of seaweed-derived polysaccharides, polyphenols and peptides to modulate the gut microbiota through diet. Polysaccharides such as fucoidan, laminarin, alginate, ulvan and porphyran are unique to seaweeds. Several studies have shown their potential to act as prebiotics and to positively modulate the gut microbiota. Prebiotics enhance bacterial populations and often their production of short chain fatty acids, which are the energy source for gastrointestinal epithelial cells, provide protection against pathogens, influence immunomodulation, and induce apoptosis of colon cancer cells. The oral bioaccessibility and bioavailability of seaweed components is also discussed, including the advantages and limitations of static and dynamic in vitro gastrointestinal models versus ex vivo and in vivo methods. Seaweed bioactives show potential for use in prevention and, in some instances, treatment of human disease. However, it is also necessary to confirm these potential, therapeutic effects in large-scale clinical trials. Where possible, we have cited information concerning these trials.

    Author(s): Emer Shannon, Michael Conlon, Maria Hayes
  • Inorganic carbon, nitrogen and phosphorus are the main elements required by seaweeds for photosynthesis and growth. This review focusses mainly on nitrogen, but the roles of carbon and phosphorus, which may interactively affect seaweed physiological processes, are also explored. Fundamental concepts such as limiting nutrients, sources, and ratios, mechanisms of nutrient uptake, nutrient assimilation and storage, patterns of uptake and preferences for different nitrogen sources are discussed. The roles of abiotic (water motion, light, temperature, salinity and desiccation) and biotic (life stages and age class) factors in nutrient (nitrogen, phosphorous, carbon) uptake are also reviewed. Understanding species-specific nitrogen physiologies and nitrogen source preferences will enable polyculture of different seaweed species and the use of seaweeds as biofilters in integrated multitrophic aquaculture systems.

    Author(s): MICHAEL Y. ROLEDA , CATRIONA L. HURD
  • A hatchery was established for the inoculation of coral chips, pebbles and lines with carpospores of Gracilaria paruispora, an edible market seaweed in Hawaii. Cystocarpic thalli were placed over various substrates in tanks of aerated seawater. Carpospores attached readily to substrates and after 72 h in hatchery tanks, mean spore density on slides placed in hatch tanks was

    1800 cmU2. Inoculated coral chips and pebbles were placed out in a seawater pond. After 18-22 weeks spore density declined to 4 cme2 but 61% of substrates still had plants. Only 36% of inoculated lines developed good growth, but growth was more rapid on lines than on pebble or chips. Lines yielded two crops per year, each approximately 800 g mm2 (fresh weight), whereas chips and pebbles required 50 weeks growth for an equivalent harvest. Tetrasporophytes were the dominant adult stage but cystocarpic plants accounted for approximately 10% of the culture products, demonstrating that the life cycle of this species was completed within the culture system. Spore culture of Gracilaria allowed mass production of plants on a variety of artificial substrates but the disadvantages included the long lag period and the lower reliability compared with vegetative production methods.

    Author(s): Edward P. Glenn, David Moore, Kevin Fitzsimmons, Celicina Azevedo
  • In theory Seaweed biomass production is severely hampered by a 10,000 fold slower diffusion rate of a Carbon source or Dissolved Inorganic Carbon (DIC) in the biophysical medium water in comparison to terrestrial C3 crops. Despite this inflicting property pelagic seaweeds outcompetes C3 crops for annual green biomass production which is called “the seaweed-paradox”Here we have reported our findings and hypothesized that for four seaweed species that due to an internal acidification the abundant oceanic bicarbonate ion (HCO3) is introduced into the cell which will in the inner acidic mitochondrial environment (matrix) rapidly be converted to COwhich is the only C-form photosynthetic enzyme ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) can react with to produce with solar energy and water green biomass. We hypothesize this intracellular acidification is performed by reversal of the fifth pump of the chemi-osmotic model of Mitchell. It can be expected that in nearby future seaweeds may play a prominent role in providing the unfettered growth of the world population -estimated at around 10 billion people at the midst of the 21st century: food, fuel and other bioactive ingredients.

    Author(s): Vincent Van Ginneken
  • Living up to its mandate of promoting agricultural development, the Department of Agriculture (DA)continuously provides policy framework, public investments, and support services intended for domestic and export-oriented business enterprises in all sectors of the Philippine agriculture both informs of government-funded and foreign-assisted projects. The Philippine Rural Development Project (PRDP), a collaborative program of the DA and an international development multilateral - the World Bank, for instance, was designed to establish the government platform for a modern, climate-smart and market-oriented agri-fishery sector. This is a six-year project (2013-2019) that aims to work hand-in-hand with the LGUs and the private sector to ensure availability of key infrastructures, facilities,technology, and information that will elevate Filipino lives by means of increasing incomes, productivity, and competitiveness especially in far-flung agricultural areas in the country.

    As an archipelagic nation, the Philippines features abundant aquatic resources that can be utilized by its inhabitants as a source of food and income. Its promising marine expanse nurtures a wide range of economically important fish species, crustaceans, and aquatic products like seaweeds. According to Legasto (1988), unlike other aquaculture commodities, the seaweed industry has not yet reached a noticeable mark in the Philippine market until 1973 when foreign revenues increased to almost fifty times because of the developments in seaweed farming. Since then its significant contribution was known and was reflected in a huge amount of PHP 466, 732,486 or about US$ 23.4 M (32.3 thousand MT) in the country and now the third most important fishery export of the Philippines.

    Seaweed is a macrobentic (large and attached) marine algae with undeniably huge ecological importance and economic potential. It has variety of uses and one of the export winners in the Philippines. With that being said, it is one of the priority thrusts of the Government under the Agrikulturang Makamasa Program for Fisheries. The industry’s significant contribution is viewed both as (a) habitat and breeding ground for many marine organisms, and (b) economy as source of human food and raw materials for phycocolloid production as well.

    The National Seaweed Development Program (NSDP) under the Bureau of Fisheries and Aquatic Resources (BFAR) was made to celebrate and to support substantial contributions of the seaweed resource to the country's fisheries production, trade and employment. It is conceptualized to implement a well-coordinated industry with responsive projects and activities on seaweeds both at the national and regional levels. The Program is designed to strengthen BFAR meeting the needs and challenges that beset the Philippines seaweed industry. Their advocacy involves (a) organizing small seaweeds farmers into cooperatives, (b) trainings for coop accreditation and seaweed production techniques, (c) providing farm implements to newly-engaged seaweed farmers, and (d) access to affordable and less stringent financing scheme through cooperatives.

    With an astounding performance of the seaweeds industry in the Philippines, a number of regions in the archipelago are the ones behind the continuous success of the sector. CALABARZON region, for instance, demonstrates a very interesting so as competitive play in the industry. The whole commodity chain – from production up to processing then marketing - can be traced just within the provinces in Region IV-A. According to PSA-BAS, the total seaweed production of CALABARZON in came solely from Quezon and Batangas with 32,425.43MT and 192.31MT in 2014, respectively, translating into roughly 99.4% share made by Quezon province. In the processing phase, however, some processing plants involved in carrageenan production has been identified in Industrial parks in Laguna and Cavite wherein they cater processing services not only for CALABARZON-produced seaweeds but the entire country as well. Marketing activities are made directly by the traders or by the processors end. It is also noteworthy that Quezon province ranked 9thspot in the Top 10 seaweeds-producing provinces in the Philippines in 2014.

    The conduct of a comprehensive Value Chain Analysis(VCA) on different commodities like seaweed is very important in the agriculture industry. That way efficiency gaps between market intermediaries from production up to consumption will be traced and consequently be addressed. This serves as the key to unlocking industry process gridlocks and facilitates maximum process effectiveness and efficiency. Everyone involved in the industry can ensure optimum profit and benefits. Thus, fostering a more successful seaweed industry to cater not only domestic but international market as well.

    The major objective of the VCA is to create informed decisions on leverage points for project/program interventions in support of the small-scale seaweed farmers in particular and the seaweeds industry as a whole. The specific objectives of the study are:
    1.Assess the value added to the product at all levels of the chain;
    2.Identify priority interventions needed to strengthen links in the value chain and attain the Philippine Rural Development Project goals;
    3.Identify possible areas for investment and/or enterprise development; and
    4.Serve as empirical basis to facilitate the translation of interventions into priority programs and projects that will enhance productivity of the seaweed industry

    Author(s):
  • Modern methods of macroalgal cultivation of the large brown seaweeds commonly and collectively referred to as ‘kelp’ began in the early 1950’s in China, with research spearheaded by ‘the father of mariculture’, Prof. CK Tseng and his team. Since this time, kelp aquaculture has steadily grown in China and other Asian countries such as Japan, and the Republic of Korea. Now, almost all of the seaweed produced for human consumption, alginates and other purposes comes from aquaculture, with the extent of cultivation clearly visible on satellite images in some regions. Research in these countries has focused on brown algal species including Saccharina japonica and Undaria pinnatifida, concentrating primarily on developing a number of commercial strains that demonstrate temperature-tolerance of warmer seawater, and latterly, on improved productivity. In China, it is common practice to have centralised seaweed hatchery facilities that produce plantlets for further on-growing at a number of local sea sites.The development of centralised facilities using controlled seaweed strains most likely lends itself to a higher degree of standardised operations during the production cycle.

    In direct contrast to the mass culture of seaweed in China and other Asian countries, commercial cultivation production in Europe remains on a small scale. While European research on kelp has existed at least as long as for that conducted in China, seaweed cultivation techniques have been known (generally only within research facilities) for approximately thirty years. For most of this time, cultivation has existed at a demonstration/pilot-scale only, although this is now changing in a number of countries, primarily across NW Europe. It was recognised early on that the Chinese method of growing seaweed by inserting small plantlets into ropes for on-growing at sea would not be economically efficient in Europe, given the cost of labour. Alternative cheaper seeding techniques, as described in this document, have been developed instead. Longline design is also different in Europe, where sea conditions are generally more challenging than the more sheltered areas that typically support Chinese aquaculture. This influences design and of course the cost of equipment that is used. The concurrent European research on wild strains of kelp species, partnered with a strong requirement for developing site specific cultivation systems has naturally led to some variance in production protocols and systems.

    The EnAlgae project has allowed its research partners in NW Europe the opportunity to use hindsight of the expansion of global seaweed cultivation to full advantage. A theme of the project(WP1, Action 5) has been ‘the development and exchange of best practice for mass production of macroalgae’. For this action to be completed satisfactorily, demonstration/pilot sites (WP1, Action 2)were constructed at the macroalgal partner facilities. The subsequent development of a close working relationship enabled production of comparable data for identified species (Saccharina latissima and Alaria esculenta) on cultivation methodology, data collection (WP1, Action 3) and macroalgal growth results. The standardisation of all of these elements was designed to produce reliable data and share common experiences between macroalgal cultivation stakeholders in NW Europe, culminating in the production of this manual, and the accompanying Macroalgal Best Practice document.

    This document is a manual of collated Standard Operating Protocols (SOPs) that were developed in the three EnAlgae macroalgal hatcheries in the National University of Ireland, Galway(NUIG), Queen’s University, Belfast (QUB) and the Centre d’Etude et de Valorisation des Algues (CEVA). It describes the set-up/requirements of each seaweed hatchery, the hatchery cultivation process, thesea on-growing process, as well as biomass and environmental parameter measurements and sampling. While some SOPs were subject to some inherent differences within each hatchery (e.g. pre-existing seawater pumping and distribution systems), an effort was made to ensure that as many elements of the SOPs were standardised across the partners. For example, the biomass sampling SOP was particularly important to enable the collection of comparable data in Ireland, Northern Ireland and France.

    The SOP manual has been designed for reading with the EnAlgae Macroalgal Best Practice document. This sister document offers further advice and observations of the methods used, including elements of the processes that worked, and equally importantly, where system failures occurred, and revisions were made. It is hoped that both documents will become a valuable resource for those interested in developing European kelp cultivation in NW Europe and beyond, providing information on techniques that can further refined, leading to ever-increasingly efficient seaweed production at sea.

    Author(s): M. Edwards , K. Mooney, E. Gorman Healey , J. Champenois
  • This report includes abstracts on papers that discuss different aspects of Phycologia. 

    Author(s): Robert A. Andersen
  • The readers chose between transformative bioenergy technologies at more than 250 companies, universities and national laboratories, including 100 organizations that received write-in votes.

    Author(s): Biofuels Digest
  • Rationale: The UK faces major choices about how to move to a secure, low carbon economy over the period to 2050. Should we do more to cut demand, or rely more on increasing and decarbonising the energy supply? How will we produce our electricity? Which technologies will we adopt?Approach: 2050 pathways is a tool to help policymakers, the energy industry and the public understand these choices. For each sector of the economy, four trajectories have been developed, ranging from little or no effort to reduce emissions or save energy (level 1) to extremely ambitious changes that push towards the physical or technical limits of what can be achieved (level 4).Pathways: The 2050 Pathways Calculator – available on the DECC website - allows users to develop their own combination of levels of change to achieve an 80% reduction in greenhouse gas emissions by 2050, while ensuring that energy supply meets demand. This report describes six different illustrative pathways to show the varied routes to 2050, ranging from a pathway that requires significant effort across all sectors to pathways with only a minimal contribution from particular sectors, such as renewables, bioenergy, nuclear or carbon capture and storage, and a pathway with less action on energy efficiency. None of them represents a preferred option.

    Author(s):

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