Production of aldehydes and functionalized polysaccharides by galactose oxidase and chemical modifications

Funding: Academy of Finland
Collaboration: Prof. Stefan Willför, Åbo Akademi University, Finland

Project description

Polysaccharides are interesting materials for various applications due to their renewability, non-toxicity, and biodegradability. The project focuses on selective modifications of polysaccharides, aiming to obtain materials with new and improved functionalities and applications.
The key technology of the project is the selective oxidation of primary alcohols to corresponding aldehydes with galactose oxidase, a 65–68 kDa single copper metalloenzyme secreted by fungus Fusarium spp (EC 1.1.3.9). The catalytic reaction of galactose oxidase comprises oxidative and reductive half-reactions, using molecular oxygen as an electron acceptor and producing hydrogen peroxide.
Polysaccharides such as spruce galactoglucomannan, guar gum, and tamarind galactoxyloglucan contain galactosyl units. The primary C-6 hydroxyl groups of the galactosyl units of the polysaccharides are selectively oxidized with galactose oxidase. The products are further modified utilizing the reactive carbonyl groups formed in the enzymatic oxidation. The focus is in techniques that are suitable for one-pot procedures performed directly after the enzymatic oxidation in aqueous media.