Biodegradable Chitin and Chitosan Polymer Material

Chitin and chitosan(s) (CS) are biopolymers that have received considerable attention due to their numerous applications in agriculture, food, textile, the paper industry, the food industry and biomedicine and so on. 

Industrial chitin is obtained from marine food production waste, i.e., crustacean shells from shrimp, crab or krill [13,14]. The processing of shrimps for human consumption generates 40-50% of the total mass of marine food production waste, which is considered to be one of the main pollutants in coastal areas, as it is dumped into the sea [15]. A small part of the waste is dried and used as chicken feed [14].The major components (on dry mass basis) of shrimp waste are chitin, minerals, carotenoids and proteins thus, the utilisation of this shell food waste as an alternative source to produce chitin may help solve environmental problems related to waste generation. 

Over 150,000 tonnes of chitin is currently harvested by utilising a by-product of the seafood industry, making it available throughout the year. Chitin and CS are currently in the spotlight due to their numerous applications in biomedicine, waste water treatment, food, cosmetics and the fibre industry [35-39]. The high nitrogen 

CS is an exciting and promising material in tissue regeneration applications as these biopolymers can be easily constructed into various forms and their derivatives are biodegradable by lysozomal enzymes. 

CS forms water-soluble salts with inorganic and organic acids including glyoxylate, pyruvate, tartarate, malate, malonate, citrate, acetate, lactate, glycolate and ascorbate. Natural CS showed more solubility in organic acids when the pH of the solution was less than 6.5. Facile water-miscible salts of CS are formed by neutralisation with acids such as lactic, hydrochloric, acetic or formic. 

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