Process for producing N-acetyl-D-glucosamine

A process for producing N-acetyl-D-glucosamine by enzymatically hydrolyzing chitin with chitinolytic, which consists essentially of:

• (a) introducing a chitin-containing solid, a carbohydrate-free media, and a microorganism which produces chitin-degrading and chitobiose-degrading enzymes when grown on chitin into a first culture fermentor vessel;
• (b) producing a fermentation broth culture in the first culture fermentor vessel by applying a culturing protocol which induces the microorganism to produce and secrete chitinolytic enzymes containing at least one chitin-degrading enzyme, which is chitinase, and one chitobiose-degrading enzyme, which is chitobiase, which are secreted by the microorganism to the extracellular fluid;
• (c) separating the chitinolytic enzymes as a filtrate from other components of the fermentation broth culture which has been formed in the first culture fermentor vessel;
• (d) introducing the separated chitinolytic enzymes filtrate and chitin-containing solids into a two-stage, packed bed and solids-free volume chitin-hydrolysis reactor separate from the first culture vessel for sufficient residence time wherein the chitin in the solids is hydrolyzed by the chitinase and the chitobiase in the chitinolytic enzymes to N-acetyl-D-glucosamine;
• (e) separating the N-acetyl-D-glucosamine which has been formed in the second reactor into a filtrate stream and the chitinolytic enzymes in the second reactor into a retentate stream;
• and
• (f) recovering the N-acetyl-D-glucosamine from the filtrate stream.