Purifying chitin and recovering the other compounds from a crustacean shell to enhance them was one of the challenges facing Ifremer’s Biotechnology and Marine Resources unit. This work, carried out in close collaboration with the NCRS GEPEA UMR, was the subject of a Ph.D. thesis (Karine Le Roux) and a post-Ph.D. research (Marius Socol). The fruitful research has led to the filing of a patent and several valuations in scientific journals or international congresses.

To meet this challenge, the unit has exploited one of its historical skills around enzymatic hydrolysis processes. The enzymatic pathway had already been explored to deproteinize the cuticles. The major innovation proposed by Ifremer and the subject of the patent is to combine deproteinization and demineralisation simultaneously by proposing an efficient process of enzymatic hydrolysis in an acid medium using a “weak” acid. Different “dietary” acids can thus be candidates for demineralization and make it possible to obtain a reaction “buffer” pH of the order of 3 to 4. Thus, many industrial proteases are able to solubilize the protein elements of the matrix and Thus enriching the aqueous phase of peptides of interest at a directly operational pH. Apart from the rapid phase of inactivation of the enzyme by the temperature, the treatment remains “soft” and thus allows the bioactive potential of this phase to be maintained. Within six hours, the chitin extracted from the carapaces reaches a high level of purity (more than 90% for many enzymes and more than 92% in the case of ASP in formic acid). This work won an award for innovative techniques for the environment in 2012.

This work constitutes one of the experimental supports for the research work on the modeling of peptide size distribution kinetics during controlled enzymatic proteolysis carried out by Ifremer’s BRM unit. The intensification of this type of reaction by physical methods (sonication, microwaves, reactive extrusion, etc.) is also the subject of collaborative research by this unit in close collaboration with the GEPEA.