Gellan Gum Introduction
Microbial exopolysaccharides have found a wide range of applications in the food, pharmaceutical and
other industries due to their unique structure and physical properties.
Some of these applications include their use as emulsifiers, stabilizers, binders, gelling agents,coagulants, lubricants, film formers, thickening and suspending agents .
These biopolymers are rapidly emerging as industrially important, and are gradually becoming economically competitive with natural gums produced from marine algae and other plants.
Microbial polysaccharides are water-soluble polymers and may be ionic or non-ionic. The repeating units
of these exopolysaccharides are regular, branched or unbranched, and are connected by glycosidic linkages. Some microbial polysaccharides are commercially accepted, while others are at various stages of development. Currently a small number of biopolymers are produced commercially on a large scale .
Among the biopolymers which are either currently commercial products or which have been the subject of extensive studies are xanthan from Xanthomonas campestris, gellan and a range of structurally related polysaccharides from the strain of Sphingomonas paucimobilis, bacterial alginates secreted by Pseudomonas sp., Azotobacter vinelandii and Azotobacter chrococcum.
Small amounts of bacterial cellulose from Acetobacter xylinium, hyaluronic acid from Streptococcus equii and succinoglycan from Rhizobium have also found application.
Gellan gum is one of the industrially useful exopolysaccharides due to its various functional properties.
It is a sphingan group of heteropolysaccharides secreted by members of the bacterial genus Sphingomonas .
Key words: Gellan gum,polysaccharides,Sphingomonas.
