Making good after a leak

[lurker]

I have discovered a long term leak behind the kitchen units.
I think I have identified and rectified the cause.

This morning I took up part of the kitchen over lay floor, underneath is black and smelly but essentially sound.
I plan to leave it to dry (this good weather will help) then reboard with some spare overlay.

Assuming I get it nice and dry, should I treat it to kill any mould?
I was thinking of plain dilute bleach

Advice welcome

 

[lurker]

To be clear, the overlay as I described it, is cheap click together Mdf laminate I fitted around 20 years ago.
I assume it's vinyl, I have just enough spare boards to make good

 

[Harbo]

Bleach should kill off the mould

Rod