Catalyzes oxidative deamination of D-amino acids, in particular D-alanine, and could be responsible for the degradation of diet-derived D-alanine in the intestine. Acts on a variety of D-amino acids with greater preference towards those with basic and aromatic groups followed by those bearing neutral groups. Has no activity against acidic D-amino acids, L-amino acids or N-methyl-L-aspartic acid. May play a role in egg-laying events and early development. a D-alpha-amino acid + H2O + O2 = a 2-oxocarboxylate + H2O2 + NH4(+) Homodimer. Belongs to the DAMOX/DASOX family.