A fed-batch bioprocess similar to that used in Monteiro et al. 2005 was used to increase spore production of B.
subtilis. The main objective was to maintain the C:N ratio (10:1) in both batch and fed-batch phases. To avoid the inhibitory effects of carbon and nitrogen sources over sporulation, an exponential and a constant feeding
profile were used for glucose and ammonium, respectively. Calcium was also added under fed-batch mode, as
precipitation occurs when concentration higher than 0.6 g∙L−1
is used in the preparation of the fermentation media.