attempted recently in the United States, Canada, and New Zealand as well; in the
U.S., giant kelp is farmed not as a food source, but as a source of alginic acid or
material for methane fermentation. In the Philippines, Gracilaria verrucosa is
farmed for export as a carrageenan source (Lüning and Pang 2003; Kraan 2013).
Recently, giant kelp has been the focus of continued attempts in the U.S. to
mass-produce seaweed as a methane fermentation resource for alternative bioenergy
development. In Japan, ocean farming has been considered for ongoing mass
production of kelp and other highly productive large varieties of brown algae.
These efforts would entail establishing large ocean farms on the coast for
year-round production and supply of seaweed as a methane fermentation resource.
The ocean farming facilities used in Japan cover an area measuring
8.05 km  5.12 km, or a total of 41.216 km
2
. This area contains 28 unit farms (each
measuring 850 m  980 m), where kelp and other large brown algae are grown
separately or together. In each unit, seedlings grown with different land production
times are transplanted and farmed for a suitable length of time, after which those that
have become particularly large are automatically harvested by harvest vessels. These
vessels are essential for automatic cultivation, but for the vessels to fully demonstrate
their capabilities, farming facilities must be in place with the structures to respond to
them efficiently.
Once harvested, seaweed is transported to methane fermentation facilities and
used as a fermentation substrate. For reasons of economy, useful ingredients are
extracted prior to fermentation. These useful ingredients include pigments, alginic
acid, water-soluble alginate, and various anti-cancer and anti-bacterial agents.
Consideration is also given to the recovery of useful ingredients from methane
fermentation residue, which include iodine, vitamins, and eicosapentaenoic acid
(EPA). Vitamin B 12 and EPA are known to be of particular physiologically and
nutritionally significance for young fish and may be used as food additives for
farmed fish (Pereira and Yarish 2008; Ugwu et al. 2008).
6.3 Tissue Culture
Various methods have been considered for the mass production of useful seaweeds.
One of these is mass seedling production through the application of tissue culture
techniques. Achieving this first requires the sterilization and successful culturing of
seaweed tissue. Because the seaweed surface is rich in mucilage, and because large
numbers of tiny flora and fauna adhere to the surface or penetrate the cell layer close to
the surface (particularly in naturally growing seaweeds), acquiring aseptic tissue is no
easy feat. Some sterilization methods that have been in use since early on include
pipette flushing (most often used for single-cell organisms such as zoospores and
regular spores), agar plate washing, UV ray exposure, ultrasound application,
antibiotic application, and germicide through the use of alcohol, iodine, or chlorine
solution. These methods are used in combination rather than individually
(Aguirre-Lipperheide et al. 1995; Kumar et al. 2004; Chen and Tayler 1978; Saga
et al. 1982).
6.2 Mass Production of Seaweeds
147
U.S., giant kelp is farmed not as a food source, but as a source of alginic acid or
material for methane fermentation. In the Philippines, Gracilaria verrucosa is
farmed for export as a carrageenan source (Lüning and Pang 2003; Kraan 2013).
Recently, giant kelp has been the focus of continued attempts in the U.S. to
mass-produce seaweed as a methane fermentation resource for alternative bioenergy
development. In Japan, ocean farming has been considered for ongoing mass
production of kelp and other highly productive large varieties of brown algae.
These efforts would entail establishing large ocean farms on the coast for
year-round production and supply of seaweed as a methane fermentation resource.
The ocean farming facilities used in Japan cover an area measuring
8.05 km  5.12 km, or a total of 41.216 km
2
. This area contains 28 unit farms (each
measuring 850 m  980 m), where kelp and other large brown algae are grown
separately or together. In each unit, seedlings grown with different land production
times are transplanted and farmed for a suitable length of time, after which those that
have become particularly large are automatically harvested by harvest vessels. These
vessels are essential for automatic cultivation, but for the vessels to fully demonstrate
their capabilities, farming facilities must be in place with the structures to respond to
them efficiently.
Once harvested, seaweed is transported to methane fermentation facilities and
used as a fermentation substrate. For reasons of economy, useful ingredients are
extracted prior to fermentation. These useful ingredients include pigments, alginic
acid, water-soluble alginate, and various anti-cancer and anti-bacterial agents.
Consideration is also given to the recovery of useful ingredients from methane
fermentation residue, which include iodine, vitamins, and eicosapentaenoic acid
(EPA). Vitamin B 12 and EPA are known to be of particular physiologically and
nutritionally significance for young fish and may be used as food additives for
farmed fish (Pereira and Yarish 2008; Ugwu et al. 2008).
6.3 Tissue Culture
Various methods have been considered for the mass production of useful seaweeds.
One of these is mass seedling production through the application of tissue culture
techniques. Achieving this first requires the sterilization and successful culturing of
seaweed tissue. Because the seaweed surface is rich in mucilage, and because large
numbers of tiny flora and fauna adhere to the surface or penetrate the cell layer close to
the surface (particularly in naturally growing seaweeds), acquiring aseptic tissue is no
easy feat. Some sterilization methods that have been in use since early on include
pipette flushing (most often used for single-cell organisms such as zoospores and
regular spores), agar plate washing, UV ray exposure, ultrasound application,
antibiotic application, and germicide through the use of alcohol, iodine, or chlorine
solution. These methods are used in combination rather than individually
(Aguirre-Lipperheide et al. 1995; Kumar et al. 2004; Chen and Tayler 1978; Saga
et al. 1982).
6.2 Mass Production of Seaweeds
147