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  • The recently domesticated marine macroalga Derbesia tenuissima is suitable for intensive land-based production and is a promising species for functional food applications and bioproducts as it is rich in bioactive components and has high biomass productivity. For the first time, we quantified the effects of inducing different degrees of light stress by managing culture conditions (as biomass density) in land-based 2000 L cultures, on the total phenolic content, antioxidant capacity (DPPH, FRAP, ABTS), and biomass and antioxidant productivity of Derbesia. We demonstrate that it is possible to manipulate the antioxidant content of Derbesia by managing culture conditions, with up to 88% higher antioxidant capacity in biomass stocked at 0.5 g L−1 than when stocked and maintained at 2 g L−1 , or stocked at 2 g L−1 and harvested weekly. Antioxidant productivity of tank-cultured D. tenuissima is high – up to 680 μmol gallic acid equivalents m−2 day−1 – and can be maximised by selecting low initial stocking densities without compromising productivity per unit land area

    Author(s): Marie Magnusson, Leonardo Mata, Na Wang, Jian Zhao, Rocky de Nys, Nicholas A. Paul
  • Eucheuma, a red alga, endemic to Philippine marine waters, is the twentieth-centure wonder plant. It is so called because of its many important uses in various industries. From this seaweed is extracted carrageenan, a valuable sustance used in products that need gelling, suspending, thickening, emulsifying and water-holding properties.

    Eucheuma thrives in some selected areas in tropical zones. In Asia, the major-producing countries are the Philippines and Indonesia with perhaps a little contribution from Singapore, Japan and Malaysia. Outside Asia, the biggest producer of a similar type of seaweed called Irish Moss is Canada. There had been noticeable decrease in the volume of outputs in those countries due to the indiscriminate harvesting of seaweed by lots of commercial investors.

    In the Philippines, the Mindanao-Sulu area is claimed to have the richest source of Eucheuma. Based on the survey of the Bureau of Fisheries and Aquatic Resources on the known Eucheuma resources of the country, the Mindanao-Sulu area occupies 42 percent of the total suitable areas. Visayas takes a share of 28.63 percent, while Palawan is estimated 13.6 percent. Luzon area has 14.68 percent (Reyes, 1977).

    Eucheuma in dried form is basically an export product of the Philippines. Most of the country's seaweeds are transported to the United States, while some find their way to Europe and Japan (Reyes, 1977).

    In 1966, it was one of the important marine export commodities of the country, totalling 800 tons worth millions of pesos most of which were harvested from the wild. But the export in the five succeeding years decreased, so that its culture was started in 1975 (Borja, 1978).

    A survey of the Genus, indicates that there are approximately 48 species described in the literature (Dawes, 1974). Six of these species represent Philippine Eucheuma (Trono, 1974). They are Eucheuma serra, E. arnoldii, E. procrusteanum, E. cottonii, E. spinosum and E. striatum (Figure 1).

    Of these six species, Eucheuma spinosum and E. striatum, locally known as “tambalang”, are best suited for commercial cultivation, however, the latter is preferred due to its wider range of tolerance to ecological changes and is easier to farm (Trono, 1977).

    Author(s): Godardo L. Juanich
  • Kappaphycus alvarezii (Doty) Doty (= Eucheuma\striatum = Kappaphycus striatum), which weregrown originally in Japan (Mairh et al., 1995)were initially cultured in Okha, west coast ofIndia. Acclimatization and large scale cultivationof this alga was achieved on the coast of Mandapam, south east coast of India, during 1995to 1997.. CSMCRI (Central Salt and Marine Chemicals Research Institute Marine Algal Research Station -CSIR), Mandapam commenced farming on R&D basis and transferred the technology forthe first time India and being cultivated in TamilNadu since 2001. PepsiCoIndia Holdings Private Limited, Gurgoan is deeply involved in the cultivation of this economically important seaweed from 2001 to June. 2008, which got the technology from CSMCRI in 2001. This company was successful in expanding cultivation activities to Tamil Nadu with 15000 bamboo rafts occupied 9 km linear coastline from Mandapam to Rameswaram in Ramanathapuram district and mono line method was adopted in Pudukkottai district in12 hectares area. Currently there are several companies such as MARINE LIXURS, Tuticorin , Prasmo Agri Pvt. Ltd, Kumbakonam are involved in cultivation and purchasing of this seaweed through buyback arrangement with SHG’s. Nearly more than 1000 fishers are involved in seaweed farming.

    Author(s): Vaibhav Mantri, CRK Reddy , Karuppanan Eswaran , Ganesan Meenakshisundaram , Sangaiya Thiruppathi
  • Several species and varieties of Caulerpa may be utilized as food in the form of fresh vegetables. These are mainly produced through gathering of natural stocks. Only C. lentillifera is commercially cultivated in ponds in the Philippines. The culture of this species started in the early 1950s in the island of Mactan, province of Cebu, Central Visayas. The accidental introduction of C. lentillifera with some other seaweed species to fishponds as fish food initiated its formal cultivation. The high demand for this alga in the local markets in metropolitan Cebu was a major factor contributing to the success of its commercial production. The species is preferred because of its delicate, light taste, soft and succulent texture. It is also a fast growing species.

    The pond culture of C. lentillifera was started by a fishfarmer in 1952 utilizing his fishponds with milkfish and shrimp. At the beginning, Caulerpa was a secondary crop to fish and shrimp but later, because of the marginal production of fish and shrimp compared to the high production of Caulerpa, the farmer shifted to Caulerpa as his major crop and milkfish and shrimp became secondary crops. Interviews made among farmers revealed that some 400 hectares of ponds are presently used for the culture of Caulerpa. Although the commercial culture of Caulerpa in ponds started more than two decades ago, it has not been successfully transferred to other parts of the Philippines as yet, with the exception of the pond and open reef culture in Calatagan, Batangas, introduced by the author in early 1980s, so that the bulk of the fresh supply of Caulerpa in Metro Manila and some bigger towns in Central Luzon still comes from Mactan, Cebu. Although local consumption statistics are not available, it is probably safe to assume that several tons of Caulerpa are transported to Metro Manila from Mactan, Cebu every month. This seaweed is always available in the local markets any day of the week. The statistics of the Bureau of Fisheries and Aquatic Resources showed that in 1982 some 827 tons of Caulerpa were exported to Japan and Denmark in fresh, brine-cured and salted form.

    The present cultivation utilizes the traditional brackishwater ponds. However, results of recent studies (Trono, 1987) have shown that water management is a primary factor in the productivity of Caulerpa, the culture of which would require a flowthrough system to facilitate water exchange. Thus, some modification of the traditional ponds such as the introduction of water control gates have to be made. Unlike pond culture of fish where water exchange is relatively infrequent (e.g., once a week or a fortnight) pond culture of Caulerpa requires more frequent water exchange in order to maintain the necessary level of nutrients required for growth and development. Some of the more progressive farmers in Mactan had through experiences, learned the importance of proper water management and achieved higher production through the introduction of some form of a flow-through system by providing both entry and exit gates for each pond compartment.

    Author(s): Gavino C. Trono Jr.
  • Three color strains of the n-carrageenan producing red alga Kappaphycus alvarezii were cultured in Dzilam, Yucata ́n, over a 6-month period using the fixed off bottom monoline culture method to determine the technical viability of producing commercially this seaweed in the tropical waters of the Yucata ́n peninsula. Seawater temperature ranged from 28 to 31 Co, with a daily fluctuation range between 25.9 and 31.9 Co. Irradiance showed a strong fluctuation along the study period with maximal recorded irradiance during April (881.8 Amol photon m-2 s-1). Ammonia accounted for 55.1–89.8% of total DIN depending on the season, and salinity did not change significantly. Temperature was the only environmental factor that explained 96% of the observed variation in K. alvarezii growth rate (R2=0.96). The highest average growth rates obtained were 6.5±1% day-1 for the red strain, 7.1±1.8% day-1 for the brown strain, and 8.1±1.6% day-1 for green strain during June. Lowest growth rates were obtained during August and September for the green strain (2.0±0.6% day-1). Despite the significant differences in growth between months no significant differences among color strains were found (P > 0.05). The growth rates of K. alvarezii were exponential during April to June. A 10-fold increase in weight was obtained after 30 days in cultivation for all the colored strains. As propagule weight increased the growth rate was reduced. Further, biomass yield (% weight gained) fluctuated as propagule weight increased and averaged 33.2±8.4% for the green, 35.4±6.0% for the red and 36.3±10.8% for the brown strain after 15 days. The highest carrageenan yield was obtained for the green strain (40.7%), whereas average carrageenan yields for the red strain were 32.7±3.9% and 37.5±1.1% for the brown. This study shows that K. alvarezii can be grown in the tropical waters of the Yucata ́n peninsula during the dry and part of the wet season. This period coincided with the closed season of the main fisheries. Thus, seaweed farming could be proposed as an alternative activity in the area.

    Author(s): Julieta Muñoz, Yolanda Freile-Pelegrín, Daniel Robledo
  • Macroscopic marine algae form an important living resource of the oceans. Seaweeds are food important for humans and animals, as well as fertilizers for plants and a source of various chemicals. Seaweeds have been gaining momentum as a new experimental system for biological research and as an integral part of integrated aquaculture systems. We all use seaweed products in our day-to-day life in some wayor other. For example, some seaweed polysaccharides are used in toothpaste, soap, shampoo,cosmetics, milk, ice cream, meat, processed food, air freshener, and many other items. In many oriental countries such as Japan, China, Korea, and others, seaweeds are diet staples.

    Author(s):
  • The science and economics of producing crops in  the sea. Intensive systems = life cycle, hatcheries, company owned farms that are usually mechanized, usually long grow out – 1 year+  (Laminaria japonica) Extensive farms = usually vegetative, no inputs, maybe coastal, short grow in ponds but usually out – 4 to 6 weeks. (Kappaphycus alvarezii)

    Author(s): Erick Ask
  • This article discusses a sustainable alternative for coastal communities in developing countries.

    Author(s): Raúl E. Rincones
  • An interview with John Forster

    Author(s): John Forster
  • French Frigate Shoals represents a relatively unpolluted tropical Pacific atoll system with algal assemblages minimally impacted by anthropogenicactivities. This study qualitatively assessed algal assemblages at 57 sites, therebyincreasing the number of algal species known from French Frigate Shoals byover 380% with 132 new records reported, four being species new to the Ha-waiian Archipelago,Bryopsis indica, Gracilaria millardetii, Halimeda distorta, andan unidentified species ofLaurencia. Cheney ratios reveal a truly tropical flora,despite the subtropical latitudes spanned by the atoll system. Multidimensionalscaling showed that the flora of French Frigate Shoals exhibits strong similarities to that of the main Hawaiian Islands and has less commonality with thatof most other Pacific island groups.

    Author(s): Peter S. Vroom, Kimberly N. Page, Kimberly A. Peyton, J. Kanekoa Kukea-Shultz

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