Pullulan is a linear homopolysaccharide of glucose, which is produced as a water-soluble, extracellular polysaccharide by certain strains of the polymorphic fungus Aureobasidium pullulans  Arnaud.

Pullulan has adhesive properties and can be used to form fibers, compression moldings, and strong, oxygen-impermeable films. In food industry, pullulan films can be employed as coating or packaging materials of dried foods, as a binder for tobacco, seed coatings and plant fertilizers, as low viscosity filler in beverages and sauces, as binder and stabilizer in food pastes, to inhibit fungal growth in foods. In pharmaceutical industry, pullulan can be used as a denture adhesive, in the sugar coated pharmaceutical compositions to prevent brownish color change of the composition. Pullulan can also be used in cosmetics, lotions, and shampoos.
Characteristics of Pullulan polysaccharide:
1.Non-toxic safety. According to the results of the acute, subacute and chronic toxicity tests of Lullulan polysaccharide, even if the dosage of Lullulan polysaccharide reaches the LD50(half lethal dose) limit of 15g/kg, it will not cause any biological toxicity and abnormal state, so it is used in food and medicine It's safe for the chemical industry and Pullulan is a prebiotic.

2. Solubility. Pullulan polysaccharide can be dissolved in water, dissolution rate than carboxymethyl cellulose, sodium alginate, polypropylene alcohol, polyvinyl alcohol more than two times faster, the solution is neutral, no ionization, no gelation, no crystallization. Different water temperatures have little effect on the dissolution properties of Pullulan, so the dissolution temperature range of pullulan is wide (0~100ºC). 
3.Stability. The molecules of Pullulan have linear structure, so compared with other polysaccharides, the aqueous solution of Pullulan is less viscous and does not form colloid. It is a neutral solution with strong adhesion. Pullulan contains almost no reducing group and only produces weak intermolecular forces with other molecules. When the pH value is below 2.5, if heated for a long time, it will partially decompose like other polysaccharides, resulting in a decrease in the viscosity of the solution.
4. Acid and alkaline resistance. Pullulan is acid-resistant but not alkali-resistant, and its pH tolerance ranges from 2.5 to 9.5.

5. Stickiness.Pullulan polysaccharide has strong viscosity. This characteristic is used in a wide range of pharmaceutical products, such as tablet adhesives and film adhesives for wound healing sites.

6. Membrane forming. Pullulan has excellent membrane forming Pullulan membrane is 10 times higher than gelatin, 10 times higher than cellophane, 30 times higher than PVDC, It is 80 times higher than LDPE(low density polyethylene) and 200 times higher than HPMC. Pure Pullulan polysaccharide film can isolate air and water molecules, etc. When pullulan polysaccharide is mixed with other substances, it can adjust the air insulation after forming the film. In addition, the Pullulan capsule has a high tensile strength.
7.Protective agent.After forming the membrane, pullulan polysaccharide can well protect the contents of its coating from oxidation and volatilization, prolong the action time of the active components, and the membrane also has a certain ability of ultraviolet resistance. After forming pullulan film, under the dry condition of the surface, it also can prevent bacteria and other infiltration. This characteristic of Pullulan is widely used in medicinal capsule shell, wettable medical bandage, animal protection, cosmetics, food film protection and other fields.
8.Decompose. Pullulan at over 250 degrees Celsius. In the natural environment, the right conditions (temperature, moisture, air), can be degraded by bacteria. Belongs to the green environmental protection natural material.