1. Sulfated glucuronoxylorhamnan (present in Ulva lactaca and Entermorpha
compressa)
2. Sulfated xyloarabinogalactan (present in Codium and Caulerpa)
3. Sulfated glucuronoxylorhamnogalactan (present in Acetabularia).
(2) Brown algae (McCandless and Craigie 1979).
These are polysaccharides unique to seaweeds, with a very broad range of usages.
1. Alginic acid: This is an acidic polysaccharide contained in Undaria pinnatifida,
Laminaria japonica, Eisenia bicyclis, and Ecklonia cava and a copolymer
polysaccharide consisting of uronic acids such as b-D-mannuronic acid and
a-L-guluronic acid. Alginic acid is reported to only exist in seaweeds, but some
species of bacteria, including Azotobacter uinelandii and Pseudmonas aeruginosa produce mucopolysaccharide that are similar to approximately 20%
acetylated alginic acid.
2. Fucoidans: These are present in Fucus, Laminaria, and Undaria, with L-fucose
and sulfated esters as their main components.
3. Sargassans: Present in Sargassum limifolium, these sulfated polysaccharides are
very similar to fucoidans but differ in containing mannose.
(3) Red algae
Red algae contain numerous useful polysaccharides that are very widely used for
industrial purposes (Stevenson and Furneaux 1991; Usov 2011).
1. Agar: Agar is contained in Gelidaceae and Kkosiraegi consists of agarose and
agaropectin. Agarose consists of two kinds of agarobiose made up of
D-galactose and 3,6-anhydro-L-galactose connected in a straight chain by an
D-1,3 linkage.
2. Carrageenan: Present in Eucheuma and Chondrus, carrageenan possesses more
D sulfate groups such as anhydrogalactose than agar. It consists of
D-mannuronic acid and L-glucaric acid.
3. Alginic acid: Known to be present at a rate of around 2% in the red alga
Serraticardia maxima and to not exist in brown algae, alginic acid was first
found in red algae.
4. Funoran: Isolated from Gloiopeltisfurcata, funorans have D-galactose and
3,6-anhydrogalactose linked together alternately in a structure similar to
agarose.
5. Porphyran: Found in Porphyratenera et al., porphyran has a structure similar to
a combination of agar and carrageenan.
6.8 Industrial Applications of Seaweeds
171
compressa)
2. Sulfated xyloarabinogalactan (present in Codium and Caulerpa)
3. Sulfated glucuronoxylorhamnogalactan (present in Acetabularia).
(2) Brown algae (McCandless and Craigie 1979).
These are polysaccharides unique to seaweeds, with a very broad range of usages.
1. Alginic acid: This is an acidic polysaccharide contained in Undaria pinnatifida,
Laminaria japonica, Eisenia bicyclis, and Ecklonia cava and a copolymer
polysaccharide consisting of uronic acids such as b-D-mannuronic acid and
a-L-guluronic acid. Alginic acid is reported to only exist in seaweeds, but some
species of bacteria, including Azotobacter uinelandii and Pseudmonas aeruginosa produce mucopolysaccharide that are similar to approximately 20%
acetylated alginic acid.
2. Fucoidans: These are present in Fucus, Laminaria, and Undaria, with L-fucose
and sulfated esters as their main components.
3. Sargassans: Present in Sargassum limifolium, these sulfated polysaccharides are
very similar to fucoidans but differ in containing mannose.
(3) Red algae
Red algae contain numerous useful polysaccharides that are very widely used for
industrial purposes (Stevenson and Furneaux 1991; Usov 2011).
1. Agar: Agar is contained in Gelidaceae and Kkosiraegi consists of agarose and
agaropectin. Agarose consists of two kinds of agarobiose made up of
D-galactose and 3,6-anhydro-L-galactose connected in a straight chain by an
D-1,3 linkage.
2. Carrageenan: Present in Eucheuma and Chondrus, carrageenan possesses more
D sulfate groups such as anhydrogalactose than agar. It consists of
D-mannuronic acid and L-glucaric acid.
3. Alginic acid: Known to be present at a rate of around 2% in the red alga
Serraticardia maxima and to not exist in brown algae, alginic acid was first
found in red algae.
4. Funoran: Isolated from Gloiopeltisfurcata, funorans have D-galactose and
3,6-anhydrogalactose linked together alternately in a structure similar to
agarose.
5. Porphyran: Found in Porphyratenera et al., porphyran has a structure similar to
a combination of agar and carrageenan.
6.8 Industrial Applications of Seaweeds
171