Cell Wall Poly
543
Part D | 22.1
22. Cell Wall Polysaccharides of Marine Algae
Andriy Synytsya, Jana Čopíková, Woo J. Kim, Yong Il Park
Marine algae are interesting as a plentiful source of
many bioactive compounds, including polysaccharides, which represent various structurally different
polymers of high diversity in monosaccharide composition, absolute and anomeric configuration,
glycosidic linkages, molecular mass, and the presence and distribution of various functional groups.
These polysaccharides are used by algae as cell
wall structural components or food reserve. Algal
polysaccharides are highly indicative for main algal
taxa. Sulfated galactans of periodical unit/linkage
sequence (agars, carrageenans) are typical for
red algae, alginates, and fucoidans for brown
algae; sulfated glucuronoxylorhamnans (ulvans)
and other sulphated glycans for green algae. Algal
cell wall polysaccharides are extracted from the
raw material and further purified by preparative
chromatography and/or chemical treatment. Many
algal polysaccharides are assigned as phycocolloids due to their good solubility in water and
their ability to create colloid systems, including
gels and films. They also demonstrate various biological activities (immunomodulation, antitumor,
anticoagulant, antiviral, and many other activities), which are prerequisites of pharmaceutical
and medicinal applications. Finally, initially inactive or weakly active natural algal polysaccharides
can be partially degraded or structurally modified
to be fitted to various medicinal applications.
22.1 Overview ............................................. 544
22.1.1
Structure of Algal Cell Walls ....... 544
22.1.2 Polysaccharides as Taxonomic
Markers of Marine Algae ........... 544
22.2 Structural Diversity of Algal
Polysaccharides ................................... 545
22.2.1 Alginates ................................. 545
22.2.2 Sulfated Galactans ................... 548
22.2.3 Fucoidans ............................... 550
22.2.4 Ulvans..................................... 554
22.2.5 Other Polysaccharides............... 555
22.3 Isolation from Algal Raw Material ......... 555
22.3.1 Extraction Procedures ............... 556
22.3.2 Purification of Crude Extracts .... 557
22.4 Algal Polysaccharides
such as Phycocolloids........................... 558
22.4.1 Alginic Acid/Alginate Gels
and Films ................................ 558
22.4.2 Gels and Films Based
on Sulfated Galactans .............. 559
22.4.3 Gelling/Film Forming
by Fucoidans and Ulvans .......... 560
22.4.4 Interaction with Other
Hydrocolloids........................... 561
22.5 Biological Activities and Medicinal
Applications ........................................ 562
22.5.1 Immunomodulation
and Related Activities............... 562
22.5.2 Antitumor and Antimutagenic
Activities ................................. 563
22.5.3 Anti-Inflammatory Activity ....... 565
22.5.4 Activities
Against Infection Agents ........... 566
22.5.5 Anticoagulant
and Antithrombotic Activities .... 567
22.5.6 Antioxidant Activities ............... 568
22.5.7 Medicinal Materials Based
on Algal Polysaccharides........... 568
22.5.8 How to Improve Algal
Polysaccharides ....................... 569
22.5.9 Partial Degradation .................. 569
22.5.10 Chemical Modification .............. 571
References................................................... 571
543
Part D | 22.1
22. Cell Wall Polysaccharides of Marine Algae
Andriy Synytsya, Jana Čopíková, Woo J. Kim, Yong Il Park
Marine algae are interesting as a plentiful source of
many bioactive compounds, including polysaccharides, which represent various structurally different
polymers of high diversity in monosaccharide composition, absolute and anomeric configuration,
glycosidic linkages, molecular mass, and the presence and distribution of various functional groups.
These polysaccharides are used by algae as cell
wall structural components or food reserve. Algal
polysaccharides are highly indicative for main algal
taxa. Sulfated galactans of periodical unit/linkage
sequence (agars, carrageenans) are typical for
red algae, alginates, and fucoidans for brown
algae; sulfated glucuronoxylorhamnans (ulvans)
and other sulphated glycans for green algae. Algal
cell wall polysaccharides are extracted from the
raw material and further purified by preparative
chromatography and/or chemical treatment. Many
algal polysaccharides are assigned as phycocolloids due to their good solubility in water and
their ability to create colloid systems, including
gels and films. They also demonstrate various biological activities (immunomodulation, antitumor,
anticoagulant, antiviral, and many other activities), which are prerequisites of pharmaceutical
and medicinal applications. Finally, initially inactive or weakly active natural algal polysaccharides
can be partially degraded or structurally modified
to be fitted to various medicinal applications.
22.1 Overview ............................................. 544
22.1.1
Structure of Algal Cell Walls ....... 544
22.1.2 Polysaccharides as Taxonomic
Markers of Marine Algae ........... 544
22.2 Structural Diversity of Algal
Polysaccharides ................................... 545
22.2.1 Alginates ................................. 545
22.2.2 Sulfated Galactans ................... 548
22.2.3 Fucoidans ............................... 550
22.2.4 Ulvans..................................... 554
22.2.5 Other Polysaccharides............... 555
22.3 Isolation from Algal Raw Material ......... 555
22.3.1 Extraction Procedures ............... 556
22.3.2 Purification of Crude Extracts .... 557
22.4 Algal Polysaccharides
such as Phycocolloids........................... 558
22.4.1 Alginic Acid/Alginate Gels
and Films ................................ 558
22.4.2 Gels and Films Based
on Sulfated Galactans .............. 559
22.4.3 Gelling/Film Forming
by Fucoidans and Ulvans .......... 560
22.4.4 Interaction with Other
Hydrocolloids........................... 561
22.5 Biological Activities and Medicinal
Applications ........................................ 562
22.5.1 Immunomodulation
and Related Activities............... 562
22.5.2 Antitumor and Antimutagenic
Activities ................................. 563
22.5.3 Anti-Inflammatory Activity ....... 565
22.5.4 Activities
Against Infection Agents ........... 566
22.5.5 Anticoagulant
and Antithrombotic Activities .... 567
22.5.6 Antioxidant Activities ............... 568
22.5.7 Medicinal Materials Based
on Algal Polysaccharides........... 568
22.5.8 How to Improve Algal
Polysaccharides ....................... 569
22.5.9 Partial Degradation .................. 569
22.5.10 Chemical Modification .............. 571
References................................................... 571