You might be able to try a light solution of bleach and water. Maybe like a cap full of bleach to a few cups of water. Make the solution to where you can barely smell the bleach, scrub the moldly area with an old toothbrush and then bake the wood in the oven at 200* for 30 minutes or so.
Did the mold grow inside your set-up, or is this a piece of wood you are getting from outside?
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