Fermented and enzymatic production of chitin/chitosan oligosaccharides by extracellular chitinases from Bacillus cereus TKU027

► This research aimed for the microbial reclamation of shrimp processing wastes. ► Production and purification of the chitinases from Bacillus cereus TKU027. ► The chitin oligosaccharides were also observed in the culture supernatant. ► The oligomers with broader distribution range were obtained by the hydrolysis.