Laminarin water-soluble

In the Phaeophyceae (brown algae), the food reserves are laminarin, a water-soluble P-D-(l- 3)-linked D-glucan and a sugar alcohol, mannitol. Laminarin contains 20-25 glucose units (Percival, 1970, 1979). 

Laminarin is the reserve carbohydrate of the sublitoral brown algae, especially Laminaria. There are two types of laminarin as regards solubility, the normal or water-insoluble laminarin (from L. cloustoni) and a soluble type (from L. digitata). These two kinds of laminarin differ only in solubility and are otherwise indistinguishable in composition and structure. They will not be further differentiated in this description. 

Similar treatment of soluble laminarin with lime-water, but at 100 for 3 hours, gives approximately the same yield of the calcium D-gluco-metasaccharinates. 

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