Chitin, a recalcitrant polymer abundantly available in marine byproducts, can lead to high-value valorisation products such as chito-oligosaccharides and chitosan. To obtain these conversion products, several enzymatic reactions are involved, of which marine bacteria are an untapped source of these enzymes. After selecting some high potential marine bacteria, a full fermentation process will be developed to extract, deproteinize, demineralize and convert chitin from crustacean waste into chito-oligosaccharides and chitosan.