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laminarin

n. (context carbohydrate English) A glucan produced by some brown algae

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Laminarin

The molecule laminarin (also known as laminaran) is a storage glucan (a polysaccharide of glucose) found in brown algae. It is used as a carbohydrate food reserve in the same way that chrysolaminarin is used by phytoplankton, especially in diatoms. It is created by photosynthesis and is made up of β(1→3)-glucan with β(1→6)-branches. It is a linear polysaccharide, with a β(1→3):β(1→6) ratio of 3:1. Its hydrolysis is catalyzed by enzymes such as laminarinase (EC 3.2.1.6) that breaks the β(1→3) bonds.