ABSTRACT
Chitin is usually distributed in marine invertebrates, insects, fungi, and yeast. Chitin is a bio polymeric substance derived from crustaceous shell a homopolymer of β (1→4) linked N-Acetyl-D-glucosamine[1]. In spite of the presence of nitrogen it may be regarded as cellulose with hydroxyl at position C-2 replaced by an acetamido group [2]. Like, cellulose functions a structural polysaccharides (Figure 15.1).Commonly, the shell of selected crustacean consists of 3040 percent protein, 30-50percent calcium carbonate and calcium phosphate and 20-30 percent chitin [3]. The prime source is shellfish water such as shrimps crabs and crawfish [4]. It isalso obtained naturally in a few species of fungi. Chitin is formed a linear chain of acetylglucosamine groups while chitosan is recovered by removing enough acetyl groups (CH3-CO) from chitin therefore the chitin molecule and the resultant product is found to be soluble in most diluted acids. The actual variation between chitin and chitosan is the acetyl content of the polymer. Chitosan having a free amino group is the most useful of chitin [5]. Chitosan is a non toxic biodegradable polymer of high molecular weight. Chitosan is a one of the promising renewable polymeric materials for their broad application in the pharmaceutical and biomedical industries for enzyme immobilization [6]. Chitosan is used in the chemical wastewater treatment and food industrial for food formulation as binding, gelling, thickening, and stabilizing agent [7].
