(R)-lactaldehyde + NAD(+) = methylglyoxal + NADH + H(+)
(r)-lactaldehyde + nad(+) = methylglyoxal + nadh + h(+)
(R)-lactaldehyde + NAD(+) = methylglyoxal + NADH + H(+)
(r)-lactaldehyde + nad(+) = methylglyoxal + nadh + h(+)