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Marine environment has various living organisms where it is the place of the first living organism that appeared almost 3,500 million years ago. Marine organisms have typical metabolic and physiological properties which give them the growth and reproductive ability in extreme conditions such as high salinity and temperature. Seaweeds are the 90% of the marine abitat, and half of these seaweeds are responsible for the global photosynthesis [1, 2].

Although, creating an acceptable and easily identifiable classification system for algae is becoming more difficult due to the emergence of new species and classes. Seaweeds, also known as macroalgae, belong to the domain Eukarya and kingdoms Plantae and Chromista. Due to being a multicellular photosynthetical organism, seaweeds can be classified after the pigmentation of the organism as, red (Rhodophyta), brown (Heterokontophyta) and green (Chlorophyta) [3].

Seaweed polysaccharide structure and chemical and functional properties are influenced by many physical, biological and environmental factors, such as harvest time, the algal species, growth media composition, extraction methods, etc. [4]. All polysaccharide types have an application in human area, especially in biological and life sciences. Seaweed polysaccharides can be classified into two, due to its place in seaweeds, as cell-wall and storage polysaccharides. Most seaweed polysaccharides are cell-wall polysaccharides, except the storage carbohydrates, are located in the cell plastids. Also, they may be classified as food grade and non-food grade polysaccharides among their usage today.

Seaweed polysaccharides, like agar [5, 6], alginates, and carrageenans [7, 8] are economically and industrially the most important products from seaweeds, commonly in food industry [9, 10]. Seaweed polysaccharides have a relation with wide range of technologies including food, pharmaceutical, biomedical, textile, paper and biodegradable packaging materials. Non-food grade class polysaccharides are fucoidan, laminaran and ulvan, which have application areas as pharmaceutical, cosmeceutical and medical [11].