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Pullulan is a non-toxic exopolysaccharide of fungi origin. It is non-toxic, non-immunogenic, non-mutagenic and non-carcinogenic [181]. It produced from Aureobasiduim pullulans [182]. Pullulan is biodegradable impermeable to oxygen, non-hygroscopic and non-reducing. Pullulan possesses oxygen barrier properties, good moisture retention and it inhibits fungal growth so it enhances the shelf-life. It is used in tissue engineering, molecular chaperones, plasma expender and surface modification. Pullulan is a linear polymer made of monomers that contain three glucose sugars linked together. For more than a decade, a Japanese firm, Hayashibara Biochemical Laboratories, has used a simple fermentation process to produce pullulan. Some feedstocks are used for this process, including the streams containing simple sugars. Pullulan can be chemically modified to produce a polymer that is either less soluble or insoluble in water. The thermal and ionic (electrical) properties of pullulans can also be altered.

It can be used as a food additive, providing bulk and texture. It is tasteless, odorless, and non-toxic. It does not break down in the presence of naturally occurring digestive enzymes and therefore has no caloric content. So, it can be used as a food additive in low-calorie foods and drinks, in place of starch or other fillers. In addition, pullulan inhibits fungal growth and has good moisture retention, and thus can be used as a preservative. Pullulan can also be used as a water-soluble, edible film for the packaging of food products. It is transparent, impermeable to oxygen, and oil- and grease-resistant. Foods can be either immersed in a solution of pullulan or coated by a polymer spray. After the pullulan coating is dried, an airtight membrane is formed. Pullulan is used as gold nanoparticles for cancer treatment, drug delivery and in controlled release of biopharmaceutical [183, 184].