The production of actinorhodin by Streptomyces coelicolor in a defined medium was examined using spore and vegetative inocula. The spore inoculum yielded higher concentrations of biomass and actinorhodin as well as a higher maximum specific growth rate compared with the vegetative inoculum. Nevertheless, the productivity of the batch culture for actinorhodin formation with vegetative inoculum was higher than that with spore inoculum.