he could have just thrown the dishes away. fortunately, instead, he looked at them under a microscope. fleming found that the area around the mold eas free of bacteria. he realized that the dangerous bactiria must have been dissilved by the mold. these dirty dishes led ti the discovery of penicilin, the first antibiotic. today, this life-saving drug is used around the world. each year there are over 80 million prescriptions written for penicilin in the u.s. alone!