Oxidase that performs selective oxidation of the terminal primary hydroxyl group of several alditols, with a reduction of O2 to H2O2. Shows highest activity on xylitol and D-sorbitol, and a poor efficiency with D-mannitol and L-threitol. an alditol + O2 = an aldose + H2O2 O2 + xylitol = D-xylose + H2O2 D-sorbitol + O2 = D-glucose + H2O2 Binds 1 FAD covalently per subunit. kcat is 13 sec(-1) with xylitol as substrate. kcat is 17 sec(-1) with D-sorbitol as substrate. kcat is 9.2 sec(-1) with D-mannitol as substrate. kcat is 6.3 sec(-1) with L-threitol as substrate. Monomer. Belongs to the oxygen-dependent FAD-linked oxidoreductase family.