Who discovered mold first?

Who discovered mold first?
Nobody "discovered" mold. It has been around for eons.

Alexander Fleming discovered that mold can inhibit the growth and spread of bacteria, and subsequently invented penicillin which led to most modern antibiotics.

This discovery was a case of serendipity, as mold from a neighboring scientist's experiment contaminated Fleming's bacteria cultures - at first Fleming was angry, until he realized that the mold was killing his bacteria...