Antibacterial activity of chitin, chitosan and its oligomers prepared from shrimp shell waste

► Chitin and chitosan were prepared from shrimp shells. ► Antibacterial activity of chitin and chitosan oligomers were assessed. ► Chitosan exhibited a bacteriostatic effect on all bacteria tested. ► Due to their higher activity, oligomers were more soluble in water. ► Chito-oligomers showed advantages as new antimicrobial agents.