Xanthan gum is an anionic polysaccharide composed of a β-(1→4)-D-glucopyranose glucan backbone with side chains of (1→3)-α-D-mannopyranose-(2→1)-β-D-glucuronic acid-(4→1)-β-D-mannopyranose on alternating residues. Approximately half of the terminal mannose residues are 4,6-pyruvated while most of the inner mannose residues are 6-acetylated. Its properties make it a useful matrix component for drug delivery systems. It forms stable drug suspensions in aqueous media and soft gels with locust bean gum or guar gum. Xanthan gum mimics the texture of lipids and is used as a control in experiments where signaling pathways initiated by consumption of lipid-containing reagents are investigated in mice.

A polysaccharide containing glucose, mannose, potassium glucuronate, acetate and pyruvate. Forms a hydrophilic colloid.