Current advances in <i>Bacillus</i> spp. fermentation and scale-up for the production of industrial enzymes and biosurfactants

This review provides a comprehensive overview of the current landscape in Bacillus spp. fermentation processes for high-value bioproducts such as proteases, amylases, and surfactin in lab-scale bioreactors, highlighting critical process features. An analysis of key findings over the past 5 years shows that an efficient fermentation requires customized bioreactor conditions dependent on the substrate, strain type, and the target product. Major challenges include overcoming foaming, ensuring oxygen mass transfer, and precisely balancing the growth and production phases. A combined approach using statistical modeling, such as response surface methodology, along with experimental validation in different bioreactor designs is recommended for the process optimization. This integrated strategy can significantly improve the efficiency, predictability, and overall success of Bacillus-based bioprocesses.