ABSTRACT
Some tree species produce sticky exudates, polymeric materials that appear on trunks and branches, caused by any mechanical action. Exudate gums are produced as a natural defense mechanism to seal the plant wound and prevent dehydration and attack by microorganisms. They are commercialized as a hard, glass-like material, sometimes impuriŽed with tannin. Structurally, exudate gums are complex heteropolysaccharides, usually associated with proteins, and containing uronic acids as constituting units. They have been used since ancient times, mainly as adhesives for mineral pigments in paintings, cosmetics and inks, and for the wrapping in the mummiŽcation process. Nowadays, exudate gums are widely used in the food, pharmaceutical, adhesive, paper, textile, and many other industries.
