Put some Borax in the wash (or soak them first also) and use hot water.
Mold Removal From Washable Clothing
Fill the washing machine up with water. Pour in 20 muleteam borax and hydrogen peroxide, and let water agitate for 1 minute. Put clothing into the machine and let agitate for 2 minutes. Let clothing soak for one hour. Let clothing go through cycle. When clothes are finished you may want to wash them a second time, following the same instructions as the first time, to ensure that all the mold spores are removed from the clothing.