The mixture was vacuum filtered and the residue was washed as above and oven dried for 2 h. Decoloration of the residue was carried out using acetone wash for 10 min and dried for 2 h at ambient temperature, followed by bleaching with 1% sodium hypochlorite solution for 5 min atambient temperature with solid to solvent ratio 1:10 (w/v). The residue obtained was then washed with tap water and vacuum dried for 2 h. Further, removal of acetyl groups from chitin was achieved by refluxing for 12 h at 110 oC using 50% sodium hydroxide with solid to solvent ratio 1:15 (w/v). The resulting chitosan (C3) obtained was washed and neutralized with tap water followed by rinsing with hot distilled water at 90 oC, filtered and oven dried at 60oC for 24 h and stored in airtight containers till further use.