Within the ChitoTex project EUCODIS Bioscience, the Fraunhofer IGB and Norwegian University of Life Sciences (NMBU) collaborated to establish a new enzyme based approach to produce chitosan for the treatment of textile fibers and yarns in a more sustainable way. EUCODIS played an important role in the screening and modification of those enzymes aiming to develop suitable expression systems as well as efficient, stable, recombinant enzymes to produce chitosan.
The Fraunhofer IGB laid the foundation for the development and purification by processing chitin from insects and subsequently converting it to chitosan by using chitin-modifying enzymes (e.g. chitinases, deacetylases, chitosanases and others). Furthermore, modifications of the enzyme activity have been achieved, leading to chitosans with desired chemical-physical properties for textile-specific applications. Those enzymes were further characterized by Fraunhofer IGB and NMBU. As a second success of EUCODIS in this project, a chitosanase was identified and characterized, which can be used for the removal of chitosan from textile fibers after weaving (“desizing”), allowing to shape this step of textile production more efficiently without harming the fibers.
EUCODIS has contributed in the development of a final enzyme cocktail for chitosan production and allowed a pre-selection of promising enzymes with regard to high production yields, helping to make chitosan production more sustainable in the future. EUCODIS’ partnering institutions will use those enzyme techniques for novel production processes for modified chitosan derivatives and functional chitosan-coated fibers and textiles.
Chitosan is a linear, short polysaccharide with a wide range of applications in biomedicine as well as in the treatment of textiles. It is produced by demineralizing and partially deacetylating naturally occurring chitin under harsh alkaline conditions. Chitin itself is a renewable resource available as a side-product from shellfish or insect processing for animal protein feed production, making it a cheap and eco-friendly raw material. The process of chitosan production on the other hand not only requires the use of acids, bases and solvents but also produces lots of waste and process water. For these reasons new, more environment friendly techniques such as enzymatic chitin processing are needed.