Mannan

Type 1: Infrequent in algae (sulfated and nonsulfated), several related heteroglycans in fungi and yeast (other sugar residues in side chains) [2].

Type 2: Widespread in yeasts as cell-surface components with variable immunodeterminants [2].

Type 3: Rhodotorula glutinis and related yeasts [2].

Type 4: Major constituent in the cell walls of ivory nut endosperm and date seeds (as microfibrils). Also occurring in siphoneous green algae (in granular form) [10].