Exo-β-1,4-xylosidase, derived from Clostridium stercorarium (EC.3.2.1.37), is an exonuclease that specifically targets the β-1,4 glycosidic bonds at the non-reducing ends of xylan and xylooligosaccharides. This enzyme requires Ca2+ ions, facilitating the hydrolysis of β-1,4 glycosidic bonds through reversible metal ion binding, consequently breaking down xylan into xylose. It is utilized in fields such as lignocellulosic bioconversion, bioethanol production, and the optimization of xylan saccharification processes.