Chitin/(chitosan), next to cellulose, is the second most plentiful biomass(derivatives). Since chitin and chitosan are nontoxic, biodegradable, easy to be film, so they have been applied in treatment of wastewater; agriculture, food and cosmetic. It's biocompatibility and widespread biological activities, in recent years, they have been the hotspot in medical and sanitary field and the extensive applications of chitosan in medical and health care field.The research of hepairnoid derivatives of chitosan is t...