(R)-propane-1,2-diol + NAD(+) = (R)-lactaldehyde + H(+) + NADH (S)-propane-1,2-diol + NAD(+) = (S)-lactaldehyde + H(+) + NADH Carbohydrate degradation; L-fucose degradation. Homodimer. Belongs to the iron-containing alcohol dehydrogenase family. Extended N-terminus. Extended N-terminus.