I tried loads of things to get mould of the sealant on the bathroom sink. We are renting and obviously the person before didn't try cleaning very often so I'm talking about serious mould. I tried lots of different cleaning products even neat bleach but this one actually worked
Dettol Mould and Mildew remover
However from the way you spell mould I'm thinking you are probably american so might not be able to get hold of this so here's the active ingrediants - look for something which contains these :-
Less than 5% nonionic surfactant , Disinfectant, (Sodium Hypochlorite 2.5% w/w 25.9g/l), Perfume, Limonene
My moneys on the sodium hypochlorite being the 'right' kind of bleach to kill the annoying stuff.
Good luck!