Chitin Extraction from Crustacean Shells Using Biological Methods – A Review
Wassila Arbia1, Leila Arbia1, Lydia Adour1,2 and Abdeltif Amrane3,4*
1Laboratory of Environmental Biotechnology and Process Engineering (BIOGEP), Department of Environmental Engineering, Polytechnic National School, 10 Avenue Hacene Badi, BP 182, El Harrach, DZ-16200 Algiers, Algeria
2Department of Chemistry, Faculty of Science, Mouloud Mammeri University of Tizi Ouzou, DZ-15000 Tizi Ouzou, Algeria
3National School of Chemistry of Rennes, CNRS, UMR 6226, Avenue du Général Leclerc, CS 50837, FR-35708 Rennes Cedex 7, France
4European University of Brittany, 5 Boulevard Laënnec, FR-35000 Rennes, France
Article history:
Received June 17, 2011
Accepted April 18, 2012
Key words:
chitin, crustacean shells, chitin extraction, biological methods
Summary:
After cellulose, chitin is the most widespread biopolymer in nature. Chitin and its derivatives have great economic value because of their biological activities and their industrial and biomedical applications. It can be extracted from three sources, namely crustaceans, insects and microorganisms. However, the main commercial sources of chitin are shells of crustaceans such as shrimps, crabs, lobsters and krill that are supplied in large quantities by the shellfish processing industries. Extraction of chitin involves two steps,demineralisation and deproteinisation, which can be conducted by two methods, chemical or biological. The chemical method requires the use of acids and bases, while the biological method involves microorganisms. Although lactic acid bacteria are mainly applied, other microbial species including proteolytic bacteria have also been successfully implemented, as well as mixed cultures involving lactic acid-producing bacteria and proteolytic microorganisms. The produced lactic acid allows shell demineralisation, since lactic acid reacts with calcium carbonate, the main mineral component, to form calcium lactate.
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