Biocatalysis has been growing over the past 30 years because of the developments in many technical fields. Due to their biocompatibility, selectivity, and specificity in material, ability to continue operating under temperature and pH conditions, and relatively high interaction, biocatalysts have become significant replacements for conventional catalytic reactions. Several methods, such as enzyme structural improvements (such as protein engineering, direct evaluation), engineering approaches (such as electrode materials, supercritical fluid extraction), and sensory preservation (such as encapsulation, CLEAS), have been developed, which together are dominant instruments in the improvement of biotransformation and the synthesis of new products. This chapter summarizes the benefits of applying a performance-based approach to biocatalyst invention and engineering in cell culture for enhancing their development in critical modules and separation.