- Pullulan is a microbial polysaccharide produced mainly by the fungus Aureobasidium pullulans, composed of repeating maltotriose units linked through α-(1→6) glycosidic bonds. Within each maltotriose unit, the glucose residues are connected by α-(1→4) linkages, giving pullulan a unique alternating structure. This distinctive arrangement provides pullulan with remarkable physicochemical properties, including excellent film-forming ability, high solubility in water, low viscosity in solution, and biodegradability. These characteristics have made it a versatile biopolymer with wide applications in food, pharmaceuticals, cosmetics, and biotechnology.
- One of pullulan’s most important features is its ability to form transparent, flexible, and oxygen-impermeable films. This property has led to its extensive use in the food industry, particularly in edible films and coatings that protect foods from oxidation and microbial spoilage while being safe for consumption. Pullulan is also used in candies, capsules, and breath strips, where it dissolves quickly in the mouth and provides a clean, non-sticky texture. Because it is tasteless and non-toxic, pullulan can be easily incorporated into various formulations without altering flavor or sensory qualities.
- In the pharmaceutical and biomedical sectors, pullulan is widely recognized for its biocompatibility, non-immunogenicity, and biodegradability, making it an excellent candidate for drug delivery systems. Pullulan-based nanoparticles and conjugates have been developed to deliver anticancer agents, proteins, and nucleic acids, with modifications allowing targeted delivery and controlled release. Its ability to conjugate with hydrophobic drugs improves solubility and bioavailability. Additionally, pullulan derivatives are being explored for tissue engineering, wound healing, and vaccine delivery. Its film-forming and encapsulation capabilities also support the stabilization of sensitive biomolecules such as enzymes and probiotics.
- Beyond health-related uses, pullulan finds applications in cosmetics and personal care products. It is often added to creams, serums, and facial masks for its film-forming and moisturizing properties, which improve product texture and skin feel. In some formulations, pullulan also provides a temporary tightening effect on the skin, making it popular in anti-aging and skin-firming products.
- Pullulan’s role in industrial biotechnology is expanding as well. Its biodegradable and environmentally friendly nature makes it a promising alternative to petroleum-derived plastics. Pullulan-based coatings and packaging materials are being developed to reduce plastic waste and support sustainability goals. Its ability to form stable, flexible films also supports applications in electronics and nanotechnology, where it can serve as a matrix or stabilizing agent.
- From a scientific standpoint, pullulan is valuable as a model polysaccharide due to its well-defined structure and conformational flexibility. Studies of its physical and chemical properties have contributed to a deeper understanding of polysaccharide–protein interactions, molecular encapsulation, and polymer dynamics.
