unish kuri bengali magazine is a most popular in india and bangladesh among young generation. unish kuri january, 2017 bengali magazine. this magazine published from kolkata, india by the ananada bazar patrika. unish kuri january, 2017 bengali magazine as pdf get from this page below. i--chitosan iyinhlangano elungiselelwe i--carbohydrate enobuthi, i--cationic, non--enobuthi enobungozi enesakhiwo esiyinkimbinkimbi samakhemikhali esakhiwa amayunithi we--glucosamine β-- (1,4) njengesakhi sawo esiyinhloko (> 80%) kanye ne--n--acetyl glucosamine amayunithi (<20%), randomly distributed along the chain. chitosan is derived from chitin through chemical or enzymatic deacetylation. the degree of deacetylation (da) determines the content of free amino groups in the structure and is used to distinguish between chitin and chitosan. chitosan shows good solubility in moderate solvents such as diluted acetic acid and offers several free amine groups as active sites. this makes chitosan advantageous over chitin in many chemical reactions. chitosan is valued for its excellent biocompatibility and biodegradability, non--toxicity, good antimicrobial activity (against bacteria and fungi), oxygen impermeability and film forming properties. in contrast to chitin, chitosan has the advantage of being water--soluble and thereby easier to handle and use in formulations. as the second most abundant polysaccharide following cellulose, the huge abundance of chitin makes it a cheap and sustainable raw material.