Most often, surface stains can be removed depending on the type of stain. Sprinkle a little kosher salt on the cutting board and then gently squeeze some lemon juice over the salt.  Use the flat side of the lemon to rub the salt and lemon juice around the stains. Acid from the lemon juice will help with disinfecting. Sprinkle some baking soda over the lemon juice and rub gently with a kitchen towel.  Rub for a few minutes, in small circles. Rinse the lemon juice and baking soda from the cutting board for a minute or two under lukewarm water. Pat dry and then air dry, do not lay the board on a flat surface, allow your board to dry upright.