Seaweed polysaccharides are divided into skeletal polysaccharides, viscous
polysaccharides, and storage polysaccharides (Percival 1979; de Souza et al. 2007;
Lahaye and Robic 2007; Costa et al. 2010).
A. Skeletal polysaccharides
The chief polysaccharide making up the seaweed’s skeleton is cellulose, but constituents differ among seaweed species. Because seaweeds grow in sea water, they
need the flexibility and resilience to withstand intense waves and currents.
(1) Green Algae
For green algae, three types of skeletal polysaccharides exist.
1. In sea lattus, Ulva sp., Enteromorpha sp., and Valoniapsis sp. (Valonia), X-ray
analysis has shown the chief constituent to be true cellulose.
2. As observed in Cladophorales and Siphonocladales, they include the cellulose I
of Chaetomorpha, with its parallel array of glucans and clear X-ray diffraction
image, and the cellulose II of Ulva sp. and Monostroma, which has some glucan
molecules in the opposite direction and an unclear diffraction image.
3. In place of cellulose with an unclear diffraction image, Codium and Acetabularia ryukyuensis polysaccharides include hemicellulose such as b-1,4-mannan,
while Caulerpa okamurai and Bryopsis plumose include hemicelluloses such as
b-1,3-xylan.
(2) Brown and Red Algae
Brown and red algae have a structure of cellulose II and hemicellulose. The
structure in Porphyra is slightly different. True red alga classes (not including
protozoans) have a dry mass of around 1–9% cellulose.
Xylan can be obtained through application of hydrochloric acid and sulfuric acid
to Porphyra umbilicalis, Laurencia pinatifida, and Rhodymenia palmate. Structurally, these are intermediate between the xylan in land plants and green algae.
Protozoan red alga classes have a structure formed with glycan and mannan rather
than cellulose.
B. Mucopolysaccharide
The mucopolysaccharide that serve a replenishing function between cells also differ
among seaweed species.
(1) Green algae
The mucopolysaccharide contained in green algae necessary include ester sulfates.
They can be grouped into the following three categories by their constituent sugars:
170
6 Seaweed Biotechnology
polysaccharides, and storage polysaccharides (Percival 1979; de Souza et al. 2007;
Lahaye and Robic 2007; Costa et al. 2010).
A. Skeletal polysaccharides
The chief polysaccharide making up the seaweed’s skeleton is cellulose, but constituents differ among seaweed species. Because seaweeds grow in sea water, they
need the flexibility and resilience to withstand intense waves and currents.
(1) Green Algae
For green algae, three types of skeletal polysaccharides exist.
1. In sea lattus, Ulva sp., Enteromorpha sp., and Valoniapsis sp. (Valonia), X-ray
analysis has shown the chief constituent to be true cellulose.
2. As observed in Cladophorales and Siphonocladales, they include the cellulose I
of Chaetomorpha, with its parallel array of glucans and clear X-ray diffraction
image, and the cellulose II of Ulva sp. and Monostroma, which has some glucan
molecules in the opposite direction and an unclear diffraction image.
3. In place of cellulose with an unclear diffraction image, Codium and Acetabularia ryukyuensis polysaccharides include hemicellulose such as b-1,4-mannan,
while Caulerpa okamurai and Bryopsis plumose include hemicelluloses such as
b-1,3-xylan.
(2) Brown and Red Algae
Brown and red algae have a structure of cellulose II and hemicellulose. The
structure in Porphyra is slightly different. True red alga classes (not including
protozoans) have a dry mass of around 1–9% cellulose.
Xylan can be obtained through application of hydrochloric acid and sulfuric acid
to Porphyra umbilicalis, Laurencia pinatifida, and Rhodymenia palmate. Structurally, these are intermediate between the xylan in land plants and green algae.
Protozoan red alga classes have a structure formed with glycan and mannan rather
than cellulose.
B. Mucopolysaccharide
The mucopolysaccharide that serve a replenishing function between cells also differ
among seaweed species.
(1) Green algae
The mucopolysaccharide contained in green algae necessary include ester sulfates.
They can be grouped into the following three categories by their constituent sugars:
170
6 Seaweed Biotechnology