natural polysaccharides, reserve and structural, composed primarily of mannose radicals.

Mannans are present in bacteria, yeast, saprophytic and other fungi, algae, and higher plants, where they form part of the cell wall. Studies of yeast and bacteria have shown that mannans are biosynthesized with the participation of energy-rich nucleoside diphosphates, from which the mannose radical is transferred to a lipid carrier and, subsequently, to the polysaccharide chain being formed. Partial enzymic hydrolysis of mannans takes place upon the action of the enzyme α-mannosidase.