If you have a particle board floor underneath your sink that is showing signs of water damage you can tear it out and replace it to prevent the growth of mold.
How to fix cabinet floor under sink.
In from all four edges.
Damp rotten particleboard holds water which promotes mold and mildew.
Water leaks are a common occurrence under kitchen sinks.
The space beneath the kitchen sink is exposed to high levels of humidity and may even be exposed to water through leaky plumbing.
Then cut out the middle section of the swollen sink base with a jigsaw.
Plywood to the interior size of the sink base.
Remove the old swollen floor.
Then trace a cutting line about 3 in.
Over time this can cause the wood under the sink to rot.
Remove the drain lines and garbage disposer if there is one to get maneuvering room.
If left unrepaired the leaks can cause significant damage to the cabinet floor by promoting wood rot warping and mold or mildew growth.